Drive Controller Overload / Overheat

What does -OHF mean?

This fault indicates that the drive controller's internal temperature has exceeded its safe operating limits, often due to sustained high motor current or insufficient cooling. This protects the drive's power components from thermal damage. The fault is triggered when the drive controller's thermal state estimate reaches 118%, necessitating a cooldown period.

Complete Troubleshooting Guide

1. 1

   Reduce the motor load if it is continuously operating at high levels or near the drive's current limit.

2. 2

   Inspect the drive controller's cooling fan for proper operation, ensuring it spins freely and is not obstructed. Clean any dust or debris from ventilation openings and heatsinks.

3. 3

   Verify the ambient temperature around the drive controller is within the manufacturer's specified range. Improve cabinet ventilation if necessary. Allow the drive to cool down completely before attempting a restart.