OHF

Drive overheat

Schneider Electric · ATV32HD11N4 Variable Speed Drive

What does OHF mean?

This fault signifies that the drive's internal temperature has exceeded its safe operating limits, indicating insufficient cooling, a blocked heatsink, or an excessive load condition. Continuous operation in an overheated state will lead to accelerated wear and potential failure of drive components (e.g., capacitors, power semiconductors). Prolonged overheating can result in complete drive breakdown.

Complete Troubleshooting Guide

  1. 1

    Check the ambient temperature around the drive and ensure it is within specified limits; move the drive to a cooler environment if necessary.

  2. 2

    Clean or replace air filters if present, and verify that all cooling fans are operating correctly and are not obstructed.

  3. 3

    Ensure adequate ventilation space around the drive according to installation guidelines. Confirm air intake and exhaust are clear.

  4. 4

    Reduce the motor load or consider a higher-capacity drive if the current unit is consistently operating at its thermal limits.