DC High Rush

What does FF80 mean?

The drive's supply voltage is excessive, exceeding 124% of the unit's voltage rating. When this occurs, the motor speed can rapidly accelerate (rush) to a trip level (40% of nominal speed), indicating a potentially damaging overvoltage condition for the drive and potentially the motor.

• Input supply voltage transients or spikes exceeding the drive's maximum input voltage rating (e.g., 400V drive seeing >500V momentarily).
• Incorrect drive nominal voltage parameter (e.g., P02-01) configured lower than the actual supply voltage.
• Failure of input voltage sensing circuit within the drive, leading to misinterpretation of supply voltage.
• Severe line voltage imbalance or phase loss causing instability in the DC bus charging.
• Faulty power module components allowing uncontrolled DC bus voltage rise.

Click steps to track your progress.

1. 1

   Measure the actual input AC supply voltage at the drive's L1/L2/L3 terminals using a true RMS voltmeter or power analyzer.

2. 2

   Verify the drive's nominal voltage parameter (e.g., P02-01) is correctly set to match the actual supply voltage.

3. 3

   Monitor the DC bus voltage (e.g., r0026) during power-up and operation to identify rapid voltage increases.

4. 4

   Inspect the input power wiring for loose connections or corroded terminals that could cause transient voltage spikes.

5. 5

   Check for the presence of severe voltage sags or swells on the supply line that could trigger an overvoltage condition when recovering.