Mains Supply Fault

What does PF Sup Err mean?

This fault indicates an issue detected in the incoming mains supply voltage. This could be due to undervoltage, overvoltage, phase loss, or imbalance. An unstable or incorrect mains supply directly impacts the drive's ability to operate correctly and can cause damage to its input stage components, leading to unreliability and potential failure.

• Undervoltage condition on one or more phases due to grid instability or overloaded supply transformer.
• Overvoltage condition caused by grid fluctuations or incorrect tap settings on the supply transformer.
• Complete loss of one or more incoming phases (e.g., blown fuse upstream, contactor failure).
• Significant voltage imbalance between phases (e.g., > 2-3%).
• Incorrectly set drive parameter for mains voltage (e.g., P1-01 (Nominal Supply Voltage) not matching actual supply).

Click steps to track your progress.

1. 1

   Measure incoming AC supply voltages at terminals L1, L2, L3 (phase-to-phase) using a calibrated multimeter.

2. 2

   Verify input fuses or upstream circuit breakers are intact and correctly rated.

3. 3

   Check parameter P1-01 (Nominal Supply Voltage) setting matches the actual measured supply voltage.

4. 4

   Contact utility provider or plant electrical maintenance to investigate upstream supply quality.

5. 5

   Ensure all input power connections to the drive are tight and free from corrosion.