Power Loss

What does F3 mean?

This fault signals that the DC bus voltage within the drive is experiencing excessive ripple, which usually indicates an unstable or insufficient incoming AC power supply. This can be caused by a complete or partial loss of one or more phases, or a significant imbalance in the supply voltage. Operating with excessive DC bus ripple can stress internal components and lead to erratic drive behavior or component failure if not addressed.

Complete Troubleshooting Guide

1. 1

   Use a multimeter or power quality analyzer to monitor the incoming AC line voltage for phase loss, voltage drops, or significant line imbalance across all three phases.

2. 2

   Inspect and test the input line fuses for the drive to ensure they are intact and correctly rated. Replace any blown or damaged fuses.

3. 3

   Verify that all incoming power connections to the drive are secure and free from corrosion.