IGBT temperature (hardware)

What does 31 mean?

The hardware-level overtemperature protection for the IGBT inverter bridge has activated, indicating an excessively high short-term overload current. This can be caused by heavy motor loading or an incorrectly sized motor. Persistent high temperatures can permanently damage the IGBTs, leading to catastrophic drive failure.

• Sustained motor overload condition causing excessive current through the IGBTs, exceeding their thermal limits.
• Inadequate cooling of the drive's heatsink due to a failed cooling fan, blocked airflow, or excessive ambient temperature.
• Short circuit or ground fault on the motor output (U, V, W) drawing very high currents through the IGBTs.
• Internal hardware fault in the IGBT driver circuit or the temperature sensing element itself.

Click steps to track your progress.

1. 1

   Check the drive's cooling fan operation and ensure heatsink fins are free from dust and debris. Verify ambient temperature is within drive specifications.

2. 2

   Measure motor current (P0-01) and compare against the motor nameplate and drive's rated current to confirm sustained overload conditions.

3. 3

   Disconnect motor cables (U, V, W) and perform a motor insulation resistance test (Megger test) and phase-to-phase resistance test to check for motor faults.

4. 4

   Inspect drive output terminals (U, V, W) and motor cable for signs of short circuits or insulation breakdown.

5. 5

   Allow the drive to cool down completely (e.g., 30 minutes) and then attempt a restart to confirm if the fault is purely thermal.