Add PID_FAN_SCALING option (#15585)

Marlin/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

Marlin/src/gcode/config/M301.cpp

@@ -38,6 +38,10 @@
  *
  *   C[float] Kc term
  *   L[int] LPQ length
+ *
+ * With PID_FAN_SCALING:
+ *
+ *   F[float] Kf term
  */
 void GcodeSuite::M301() {
 
@@ -56,6 +60,10 @@ void GcodeSuite::M301() {
       NOLESS(thermalManager.lpq_len, 0);
     #endif
 
+    #if ENABLED(PID_FAN_SCALING)
+      if (parser.seen('F')) PID_PARAM(Kf, e) = parser.value_float();
+    #endif
+
     thermalManager.updatePID();
     SERIAL_ECHO_START();
     #if ENABLED(PID_PARAMS_PER_HOTEND)
@@ -65,9 +73,12 @@ void GcodeSuite::M301() {
                     " i:", unscalePID_i(PID_PARAM(Ki, e)),
                     " d:", unscalePID_d(PID_PARAM(Kd, e)));
     #if ENABLED(PID_EXTRUSION_SCALING)
-      //Kc does not have scaling applied above, or in resetting defaults
       SERIAL_ECHOPAIR(" c:", PID_PARAM(Kc, e));
     #endif
+    #if ENABLED(PID_FAN_SCALING)
+      SERIAL_ECHOPAIR(" f:", PID_PARAM(Kf, e));
+    #endif
+
     SERIAL_EOL();
   }
   else

Marlin/src/inc/SanityCheck.h

@@ -229,6 +229,8 @@
   #error "LCD_PIN_RESET is now LCD_RESET_PIN. Please update your pins definitions."
 #elif defined(EXTRUDER_0_AUTO_FAN_PIN) || defined(EXTRUDER_1_AUTO_FAN_PIN) || defined(EXTRUDER_2_AUTO_FAN_PIN) || defined(EXTRUDER_3_AUTO_FAN_PIN)
   #error "EXTRUDER_[0123]_AUTO_FAN_PIN is now E[0123]_AUTO_FAN_PIN. Please update your Configuration_adv.h."
+#elif defined(PID_FAN_SCALING) && FAN_COUNT <= 0
+  #error "PID_FAN_SCALING needs at least one fan enabled."
 #elif defined(min_software_endstops) || defined(max_software_endstops)
   #error "(min|max)_software_endstops are now (MIN|MAX)_SOFTWARE_ENDSTOPS. Please update your configuration."
 #elif ENABLED(Z_PROBE_SLED) && defined(SLED_PIN)

Marlin/src/lcd/menu/menu_advanced.cpp

@@ -289,7 +289,7 @@ void menu_cancelobject();
     //
 
     #if ENABLED(PID_EDIT_MENU)
-      #define _PID_BASE_MENU_ITEMS(N) \
+      #define __PID_BASE_MENU_ITEMS(N) \
         raw_Ki = unscalePID_i(PID_PARAM(Ki, N)); \
         raw_Kd = unscalePID_d(PID_PARAM(Kd, N)); \
         EDIT_ITEM_N(float52sign, N, MSG_PID_P_E, &PID_PARAM(Kp, N), 1, 9990); \
@@ -297,9 +297,17 @@ void menu_cancelobject();
         EDIT_ITEM_N(float52sign, N, MSG_PID_D_E, &raw_Kd, 1, 9990, []{ copy_and_scalePID_d(N); })
 
       #if ENABLED(PID_EXTRUSION_SCALING)
+        #define _PID_BASE_MENU_ITEMS(N) \
+          __PID_BASE_MENU_ITEMS(N); \
+          EDIT_ITEM_N(float3, N, MSG_PID_C_E, &PID_PARAM(Kc, N), 1, 9990)
+      #else
+        #define _PID_BASE_MENU_ITEMS(N) __PID_BASE_MENU_ITEMS(N)
+      #endif
+
+      #if ENABLED(PID_FAN_SCALING)
         #define _PID_EDIT_MENU_ITEMS(N) \
           _PID_BASE_MENU_ITEMS(N); \
-          EDIT_ITEM_N(float3, N, MSG_PID_C_E, &PID_PARAM(Kc, N), 1, 9990)
+          EDIT_ITEM(float3, PID_LABEL(MSG_PID_F,N), &PID_PARAM(Kf, N), 1, 9990)
       #else
         #define _PID_EDIT_MENU_ITEMS(N) _PID_BASE_MENU_ITEMS(N)
       #endif

Marlin/src/module/configuration_store.cpp

@@ -37,7 +37,7 @@
  */
 
 // Change EEPROM version if the structure changes
-#define EEPROM_VERSION "V72"
+#define EEPROM_VERSION "V73"
 #define EEPROM_OFFSET 100
 
 // Check the integrity of data offsets.
@@ -242,7 +242,7 @@ typedef struct SettingsDataStruct {
   //
   // PIDTEMP
   //
-  PIDC_t hotendPID[HOTENDS];                            // M301 En PIDC / M303 En U
+  PIDCF_t hotendPID[HOTENDS];                           // M301 En PIDCF / M303 En U
   int16_t lpq_len;                                      // M301 L
 
   //
@@ -785,13 +785,14 @@ void MarlinSettings::postprocess() {
     {
       _FIELD_TEST(hotendPID);
       HOTEND_LOOP() {
-        PIDC_t pidc = {
+        PIDCF_t pidcf = {
                        PID_PARAM(Kp, e),
           unscalePID_i(PID_PARAM(Ki, e)),
           unscalePID_d(PID_PARAM(Kd, e)),
-                       PID_PARAM(Kc, e)
+                       PID_PARAM(Kc, e),
+                       PID_PARAM(Kf, e)
         };
-        EEPROM_WRITE(pidc);
+        EEPROM_WRITE(pidcf);
       }
 
       _FIELD_TEST(lpq_len);
@@ -1586,16 +1587,19 @@ void MarlinSettings::postprocess() {
       //
       {
         HOTEND_LOOP() {
-          PIDC_t pidc;
+          PIDCF_t pidcf;
-          EEPROM_READ(pidc);
+          EEPROM_READ(pidcf);
           #if ENABLED(PIDTEMP)
-            if (!validating && pidc.Kp != DUMMY_PID_VALUE) {
+            if (!validating && pidcf.Kp != DUMMY_PID_VALUE) {
               // Scale PID values since EEPROM values are unscaled
-              PID_PARAM(Kp, e) = pidc.Kp;
+              PID_PARAM(Kp, e) = pidcf.Kp;
-              PID_PARAM(Ki, e) = scalePID_i(pidc.Ki);
+              PID_PARAM(Ki, e) = scalePID_i(pidcf.Ki);
-              PID_PARAM(Kd, e) = scalePID_d(pidc.Kd);
+              PID_PARAM(Kd, e) = scalePID_d(pidcf.Kd);
               #if ENABLED(PID_EXTRUSION_SCALING)
-                PID_PARAM(Kc, e) = pidc.Kc;
+                PID_PARAM(Kc, e) = pidcf.Kc;
+              #endif
+              #if ENABLED(PID_FAN_SCALING)
+                PID_PARAM(Kf, e) = pidcf.Kf;
               #endif
             }
           #endif
@@ -2446,6 +2450,10 @@ void MarlinSettings::reset() {
       #if ENABLED(PID_EXTRUSION_SCALING)
         PID_PARAM(Kc, e) = DEFAULT_Kc;
       #endif
+
+      #if ENABLED(PID_FAN_SCALING)
+        PID_PARAM(Kf, e) = DEFAULT_Kf;
+      #endif
     }
   #endif
 
@@ -3003,6 +3011,9 @@ void MarlinSettings::reset() {
             SERIAL_ECHOPAIR(" C", PID_PARAM(Kc, e));
             if (e == 0) SERIAL_ECHOPAIR(" L", thermalManager.lpq_len);
           #endif
+          #if ENABLED(PID_FAN_SCALING)
+            SERIAL_ECHOPAIR(" F", PID_PARAM(Kf, e));
+          #endif
           SERIAL_EOL();
         }
       #endif // PIDTEMP

Marlin/src/module/temperature.cpp

@@ -872,6 +872,15 @@ void Temperature::min_temp_error(const heater_ind_t heater) {
             }
           #endif // PID_EXTRUSION_SCALING
 
+          #if ENABLED(PID_FAN_SCALING)
+            if (thermalManager.fan_speed[active_extruder] > PID_FAN_SCALING_MIN_SPEED) {
+              work_pid[ee].Kf = PID_PARAM(Kf, ee) + (PID_FAN_SCALING_LIN_FACTOR) * thermalManager.fan_speed[active_extruder];
+              pid_output += work_pid[ee].Kf;
+            }
+            //pid_output -= work_pid[ee].Ki;
+            //pid_output += work_pid[ee].Ki * work_pid[ee].Kf
+          #endif // PID_FAN_SCALING
+
           LIMIT(pid_output, 0, PID_MAX);
         }
         temp_dState[ee] = temp_hotend[ee].celsius;

Marlin/src/module/temperature.h

@@ -55,15 +55,23 @@ typedef enum : int8_t {
 // PID storage
 typedef struct { float Kp, Ki, Kd;     } PID_t;
 typedef struct { float Kp, Ki, Kd, Kc; } PIDC_t;
-#if ENABLED(PID_EXTRUSION_SCALING)
+typedef struct { float Kp, Ki, Kd, Kf; } PIDF_t;
-  typedef PIDC_t hotend_pid_t;
+typedef struct { float Kp, Ki, Kd, Kc, Kf; } PIDCF_t;
-  #if LPQ_MAX_LEN > 255
+
-    typedef uint16_t lpq_ptr_t;
+typedef
+  #if BOTH(PID_EXTRUSION_SCALING, PID_FAN_SCALING)
+    PIDCF_t
+  #elif ENABLED(PID_EXTRUSION_SCALING)
+    PIDC_t
+  #elif ENABLED(PID_FAN_SCALING)
+    PIDF_t
   #else
-    typedef uint8_t lpq_ptr_t;
+    PID_t
   #endif
-#else
+hotend_pid_t;
-  typedef PID_t hotend_pid_t;
+
+#if ENABLED(PID_EXTRUSION_SCALING)
+  typedef IF<(LPQ_MAX_LEN > 255), uint16_t, uint8_t>::type lpq_ptr_t;
 #endif
 
 #define DUMMY_PID_VALUE 3000.0f
@@ -77,6 +85,12 @@ typedef struct { float Kp, Ki, Kd, Kc; } PIDC_t;
   #else
     #define _PID_Kc(H) 1
   #endif
+
+  #if ENABLED(PID_FAN_SCALING)
+    #define _PID_Kf(H) Temperature::temp_hotend[H].pid.Kf
+  #else
+    #define _PID_Kf(H) 0
+  #endif
 #else
   #define _PID_Kp(H) DUMMY_PID_VALUE
   #define _PID_Ki(H) DUMMY_PID_VALUE

config/default/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/3DFabXYZ/Migbot/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/ADIMLab/Gantry v1/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/ADIMLab/Gantry v2/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/AlephObjects/TAZ4/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Alfawise/U20-bltouch/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Alfawise/U20/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/AliExpress/UM2pExt/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Anet/A2/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Anet/A2plus/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Anet/A6/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Anet/A8/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Anet/A8plus/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Anet/E16/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/AnyCubic/i3/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/ArmEd/Configuration_adv.h

@@ -201,6 +201,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/BIBO/TouchX/cyclops/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/BIBO/TouchX/default/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/BQ/Hephestos/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/BQ/Hephestos_2/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/BQ/WITBOX/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Cartesio/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Creality/CR-10/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Creality/CR-10S/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Creality/CR-10_5S/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Creality/CR-10mini/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Creality/CR-20 Pro/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Creality/CR-20/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Creality/CR-8/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Creality/Ender-2/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Creality/Ender-3/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Creality/Ender-4/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Creality/Ender-5/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Dagoma/Disco Ultimate/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/EVNOVO (Artillery)/Sidewinder X1/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Einstart-S/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/FYSETC/AIO_II/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/FYSETC/Cheetah 1.2/BLTouch/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/FYSETC/Cheetah 1.2/base/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/FYSETC/Cheetah/BLTouch/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/FYSETC/Cheetah/base/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/FYSETC/F6_13/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Felix/DUAL/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Felix/Single/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/FlashForge/CreatorPro/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/FolgerTech/i3-2020/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Formbot/Raptor/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Formbot/T_Rex_2+/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Formbot/T_Rex_3/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Geeetech/A10/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Geeetech/A10M/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Geeetech/A20M/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Geeetech/MeCreator2/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Geeetech/Prusa i3 Pro C/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Geeetech/Prusa i3 Pro W/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/HMS434/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Infitary/i3-M508/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/JGAurora/A1/Configuration_adv.h

@@ -202,6 +202,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/JGAurora/A5/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/JGAurora/A5S/Configuration_adv.h

@@ -202,6 +202,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/MakerParts/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Malyan/M150/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Malyan/M200/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Micromake/C1/enhanced/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Mks/Robin/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Mks/Sbase/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/RapideLite/RL200/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/RigidBot/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/SCARA/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/STM32/Black_STM32F407VET6/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Sanguinololu/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Tevo/Michelangelo/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Tevo/Tarantula Pro/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Tevo/Tornado/V1 (MKS Base)/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Tevo/Tornado/V2 (MKS GEN-L)/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/TheBorg/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/TinyBoy2/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Tronxy/X3A/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Tronxy/X5S-2E/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/UltiMachine/Archim1/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/UltiMachine/Archim2/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/VORONDesign/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Velleman/K8200/Configuration_adv.h

@@ -210,6 +210,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Velleman/K8400/Dual-head/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Velleman/K8400/Single-head/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/WASP/PowerWASP/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Wanhao/Duplicator 6/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Wanhao/Duplicator i3 2.1/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/Wanhao/Duplicator i3 Mini/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/delta/Anycubic/Kossel/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/delta/Dreammaker/Overlord/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/delta/Dreammaker/Overlord_Pro/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**

config/examples/delta/FLSUN/auto_calibrate/Configuration_adv.h

@@ -197,6 +197,56 @@
     #define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
     #define LPQ_MAX_LEN 50
   #endif
+
+  /**
+   * Add an experimental additional term to the heater power, proportional to the fan speed.
+   * A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
+   * You can either just add a constant compensation with the DEFAULT_Kf value
+   * or follow the instruction below to get speed-dependent compensation.
+   *
+   * Constant compensation (use only with fanspeeds of 0% and 100%)
+   * ---------------------------------------------------------------------
+   * A good starting point for the Kf-value comes from the calculation:
+   *   kf = (power_fan * eff_fan) / power_heater * 255
+   * where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
+   *
+   * Example:
+   *   Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
+   *   Kf = (2.4W * 0.8) / 40W * 255 = 12.24
+   *
+   * Fan-speed dependent compensation
+   * --------------------------------
+   * 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
+   *    Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
+   *    If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
+   *    drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
+   * 2. Note the Kf-value for fan-speed at 100%
+   * 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
+   * 4. Repeat step 1. and 2. for this fan speed.
+   * 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
+   *    PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
+   */
+  //#define PID_FAN_SCALING
+  #if ENABLED(PID_FAN_SCALING)
+    //#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
+    #if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
+      // The alternative definition is used for an easier configuration.
+      // Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
+      // DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
+
+      #define PID_FAN_SCALING_AT_FULL_SPEED 13.0        //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
+      #define PID_FAN_SCALING_AT_MIN_SPEED 6.0          //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
+      #define PID_FAN_SCALING_MIN_SPEED 10.0            // Minimum fan speed at which to enable PID_FAN_SCALING
+
+      #define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
+      #define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
+
+    #else
+      #define PID_FAN_SCALING_LIN_FACTOR (0)             // Power loss due to cooling = Kf * (fan_speed)
+      #define DEFAULT_Kf 10                              // A constant value added to the PID-tuner
+      #define PID_FAN_SCALING_MIN_SPEED 10               // Minimum fan speed at which to enable PID_FAN_SCALING
+    #endif
+  #endif
 #endif
 
 /**