diff --git a/config/examples/BigTreeTech/SKR Mini E3 1.0/Configuration_adv.h b/config/examples/BigTreeTech/SKR Mini E3 1.0/Configuration_adv.h
index 9048e81614b986528ad18bc72ec5095e78ebb671..9054571716617c01634d692a0c169dc8ec0de712 100644
--- a/config/examples/BigTreeTech/SKR Mini E3 1.0/Configuration_adv.h
+++ b/config/examples/BigTreeTech/SKR Mini E3 1.0/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
/**
@@ -960,6 +1010,8 @@
*/
//#define POWER_LOSS_RECOVERY
#if ENABLED(POWER_LOSS_RECOVERY)
+ //#define BACKUP_POWER_SUPPLY // Backup power / UPS to move the steppers on power loss
+ //#define POWER_LOSS_ZRAISE 2 // (mm) Z axis raise on resume (on power loss with UPS)
//#define POWER_LOSS_PIN 44 // Pin to detect power loss
//#define POWER_LOSS_STATE HIGH // State of pin indicating power loss
//#define POWER_LOSS_PULL // Set pullup / pulldown as appropriate
diff --git a/config/examples/BigTreeTech/SKR Mini E3 1.2/Configuration_adv.h b/config/examples/BigTreeTech/SKR Mini E3 1.2/Configuration_adv.h
index 56710f3d2a790f5b7b3abd97cedf6641c01c4488..7bdbe0e295fb403442a105a976bd9f069f560d4b 100644
--- a/config/examples/BigTreeTech/SKR Mini E3 1.2/Configuration_adv.h
+++ b/config/examples/BigTreeTech/SKR Mini E3 1.2/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
/**