Issue:
Drive is tripping on Supply Mains UnderV (USF) fault code.

Product line:
Altivar Process, ATV630, ATV930, Altivar 600, Altivar 900

Resolution:
Measure the line voltage with a meter.  Confirm the voltage reading matches on the Drive under the Main Menu > Display > Drive Parameters > Mains Voltage.

Check the settings for Undervoltage.  Go to Complete Settings > Error/Warning Handling > Undervoltage handling.
Mains Voltage (URES) should match the measured and monitored line voltage.  For example, if using a 240V drive and the supply voltage is only 208V then change Mains Voltage to 200 VAC.  If using a 480V drive and your supply voltage is 450-470V, then change the Mains Voltage to 460V.

UnderVolt Timeout (UST) - factory setting is 0.2 seconds.  Try increasing this to ride through a momentary voltage sag.

**

If this article does not answer your question, check out our FAQ database that has answers to more commonly asked questions: Frequently Asked Questions - Schneider Electric (se.com)

If this FAQ did not solve your issue, you can call us at 1-888-778-2733 Option 2 and then 4 or e-mail us at drive.products.support@se.com to create a case with our Technical Support Team.

If you are not located in North America, please contact your local Customer Care Center for assistance: Support | Schneider Electric Global (se.com)

Released for:Schneider Electric USA