Cause : Motor fan comes when no feedback received from external fan due to faulty fan or hardware issue in drive power card.

A motor fan fault A781 in an ABB ACS880 drive indicates that there is an issue with the cooling fan of the motor, which is crucial for preventing the motor from overheating.

1. Check external fan (or other equipment controlled) by the logic.
2. Check settings of parameters 35.100…35.106.