Earth leakage warning

What does A2B3 mean?

The drive has detected an earth (ground) fault or current unbalance in the motor or motor cable, but it is configured to issue a warning rather than trip. While allowing continued operation, this indicates a potentially developing safety issue or insulation degradation that requires immediate attention before it escalates to a full fault.

• Minor insulation degradation in motor winding or motor cable, not yet a critical fault but trending towards failure.
• Capacitive leakage current in long motor cables exceeding the drive's warning threshold (e.g., parameter P99.03 for leakage current limit).
• Accumulation of conductive dust or moisture in the motor terminal box or drive output compartment.
• Improperly grounded motor frame or compromised shield connection on the motor cable.
• Faulty current sensor inside the drive detecting a false earth leakage condition.

Click steps to track your progress.

1. 1

   De-energize the drive. Disconnect the motor cable from the drive output.

2. 2

   Measure insulation resistance of each motor cable conductor to ground (PE) and between conductors using a megohmmeter (500V or 1000V).

3. 3

   Measure insulation resistance of each motor winding to ground (motor frame) and between phases using a megohmmeter (500V or 1000V).

4. 4

   Clean and inspect the motor terminal box and drive output terminal compartment for dust, moisture, or foreign objects.

5. 5

   Verify the motor frame is securely bonded to the system's protective earth (PE) ground, and cable shields are properly terminated at both ends.