Earth leakage

What does A2B3 mean?

The ACS880 drive detected an earth fault or current unbalance in the motor or the motor cable. This indicates a leakage current to ground, which can be a safety hazard or damage equipment, generating a warning.

• Insulation failure in the motor power cable, allowing current to flow to ground.
• Motor winding insulation breakdown due to age, moisture, or overheating.
• Moisture, dirt, or contaminants in motor or cable terminal connections causing a leakage path.
• Incorrect setting of parameter 31.20 Earth fault, where the drive is configured to generate a 'Warning' for this condition.

Click steps to track your progress.

1. 1

   Immediately de-energize and lock out the drive before performing checks.

2. 2

   Inspect the motor power cables for visible damage to insulation, especially where they enter conduit or motor terminal boxes.

3. 3

   Check the motor terminal box for moisture, dirt, or loose connections that could create a leakage path.

4. 4

   Measure insulation resistance between each motor phase and ground, and between phases, using a megger (e.g., 500VDC) to identify potential earth faults (expect >1MΩ).

5. 5

   Verify parameter 31.20 Earth fault is set appropriately for the application (e.g., 'Warning' for monitoring or 'Fault' for tripping on severe conditions).