UNDERVOLTAGE

What does USF mean?

This fault indicates insufficient line supply voltage, a transient voltage dip, or a damaged precharge resistor. The drive trips if the line voltage drops below specific thresholds: 160V for ATV312 M2/M3 models, 300V for N4 models, and 430V for S6 models.

• Insufficient line supply voltage to the drive.
• A transient voltage dip (brownout) on the power line.
• Damage to the internal precharge resistor of the drive.

Click steps to track your progress.

1. 1

   Measure the incoming line voltage at the drive's input terminals and verify it meets the drive's specifications, considering the tripping thresholds (160V for M2/M3, 300V for N4, 430V for S6).

2. 2

   If the precharge resistor is damaged, the drive may need to be replaced.