Old Hand Fault Finder

Allen-Bradley PowerFlex 525 F005: OverVoltage

Cites the manual · line-by-line check pending

What it means DC bus voltage went too high, usually from energy coming back from the motor.

Likely causes

  • Decel time too short
  • Overhauling load
  • High line voltage
  • No braking resistor

Checks, in order

  1. Lengthen decel
  2. Check line voltage
  3. Consider bus regulation or a dynamic brake

Old Hand tip

Fast-stopping a heavy fan is the classic cause.

Source

Source (reworded, not copied): Rockwell Automation, PowerFlex 520-Series AC Drives User Manual, publication 520-UM001O-EN-E (September 2025), Chapter 4 Troubleshooting. Official manual (PDF). Fault numbers and names can differ between firmware versions.