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, but the actual thresholds are model-dependent. Check the value description in the emGUI, the actual limitation value is displayed there and varies between different controllers.
This value does not indicate a real temperature (like °C).
I²R temperature
There is also an I²R limitation implemented. This limitation predicts temperature from the actual current reading in each phase separately in the power stage. This limitation is hard-coded and can not be overriden. The I²R limiter is typically active at standstill (or at very low rpm), when majority of the current is flowing through only one of the phases for significant time duration.