How Can I Safely Simulate a Fault on an Altivar Drive to Test Redundant System Operation?

This procedure explains how to safely simulate a drive fault to verify that a redundant system correctly detects the failure and switches to a backup drive. This procedure can be useful as well if customers need to test the behavior of drive when faulted.

Recommended Methods:

Method 1: Output Phase Loss Simulation (Preferred)
This method creates a fault without risking damage to equipment.

1. Power down the drive.
2. Disconnect the motor leads from all three drive output terminals.
3. Verify that Output Phase Loss monitoring is enabled on the drive
   (parameter location varies by model — refer to the drive’s programming manual).
4. Issue a RUN command with the motor disconnected.

Result:
The drive will detect an output phase loss and generate a fault.
Common fault codes may include OPF, OPF2, EPHO, or similar, depending on the drive model.

Method 2: External Fault via Logic Input

1. Assign an External Fault function to a logic input.
2. Trigger the input using a momentary contact closure.

Result:
The drive will immediately fault, allowing you to confirm fault detection and system switchover behavior.

Always follow proper lockout/tagout and safety procedures. Refer to the specific Altivar programming manual for parameter names and locations.