UV1

Undervoltage (Input Power)

Yaskawa · VS-616G5 Variable Speed Drive

What does UV1 mean?

This fault (PUV) indicates that the input DC bus voltage has dropped below a safe operating level. This can be caused by a momentary power loss, a significant voltage sag in the incoming AC supply, or issues with the input power supply circuit. An undervoltage condition prevents the inverter from adequately controlling the motor and can lead to unstable operation or damage to internal components.

Complete Troubleshooting Guide

  1. 1

    Check the incoming AC line voltage at the inverter input terminals for stability and correct levels.

  2. 2

    Inspect for loose connections or corroded terminals in the input power circuit.

  3. 3

    Verify the capacity of the power supply and cabling is sufficient for the inverter's requirements.

  4. 4

    Review the power grid for sags or brownouts, possibly necessitating a UPS or line reactor.

  5. 5

    Cycle power to the inverter after verifying input voltage stability.