DC Bus Undervoltage

What does UV1 mean?

The DC bus voltage fell below its trip point (≤190Vdc for 208-240Vac Drives; ≤380Vdc for 480Vac Drives). This is often due to low input voltage at the R/L1, S/L2, and T/L3 terminals, an acceleration time set too short, or excessive input voltage fluctuations, risking drive instability or shutdown.

Complete Troubleshooting Guide

1. 1

   Check the input circuit voltage at R/L1, S/L2, and T/L3 and increase input power if it's below specifications.

2. 2

   Extend the acceleration time in parameter C1-01 to prevent excessive current draw and voltage sag during ramp-up.

3. 3

   Monitor the input voltage for large fluctuations and address any power supply instability issues.