ABB · ACS880
The drive trips on this fault when an earth fault or significant current unbalance is detected in the motor or motor cable. This indicates a severe insulation breakdown or a direct short to ground, posing a risk of equipment damage, electric shock, or fire.
Click steps to track your progress.
1. Disconnect the motor cable from the drive. Perform a comprehensive insulation resistance test (e.g., 1000VDC Megger) on each motor phase cable (U, V, W) to ground (PE).
2. With the motor cable still disconnected from the drive, perform an insulation resistance test on the motor windings (U, V, W to motor frame/ground).
3. Thoroughly inspect the motor terminal box and drive output terminals for any signs of moisture, carbon tracking, or visible short circuits.
4. Visually inspect the entire length of the motor cable for severe mechanical damage, cuts, or crushing that could expose conductors to ground.
5. If the motor and cable test good, disconnect all output filters (if any) and re-test the drive itself for internal earth faults using a specialized test procedure.