Over-temperature

All these temperature readings are used for the controller's protection. If one of the temperature readings exceeds the limit, the controller will limit the motor current to prevent damage to the controller.

If there is an active limitation from one of next inputs, the Over-temp flag is raised in the /driver/state variable.

temp [°C]

The controller's internal average temperature. The temperature precision is around +-3°C. Due to self-heating of the surrounding components, the temperature reaches around 30-40°C in room temperature even in the idle mode (depends on the particualar hardware).

Temperature	Limitation
Below 90°C	No limitation
90°C	Starting limitation temperature
100°C	Full limitation

ptctemp [-]

Limit temperature sensor state. The value of 0-200 usually indicates is no limitation. Check the value description in the emGUI, the actual limitation value is displayed there and varies between different controllers.

This value can not be converted to a temperature (like °C) because the sensor is non-linear PTC sensor.

I2R temperature

There is also an I2R limitation in the controller. This limitation predicts temperature from the actual current in the power stage. This limitation does not have any setting, it is hard-coded in the firmware. The I2R limiter is active only at standstill (or very low rpm). When the motor is spinning, the current is evenly distributed between all the phases and the I2R limiter is not active.