Old Hand Fault Finder

Allen-Bradley PowerFlex 525 F059: Safety Open

What it means Both safety inputs (Safety 1 and Safety 2) are not enabled.

✓ Checked against the manual (Oct 2026): meaning and actions match the official fault table. Manual page.

Likely causes

  • Safety circuit open
  • On an install that does not use safety, the jumper on S1, S2 and S+ is missing or loose

Checks, in order

  1. Check the safety input signals and STO wiring
  2. If safety is not used, verify and tighten the jumper on S1, S2 and S+

Old Hand tip

Never bypass a safety circuit that is in use to get running.

Source

Source (reworded, not copied): Rockwell Automation, PowerFlex 520-Series AC Drives User Manual, publication 520-UM001O-EN-E (September 2025), Chapter 4 Troubleshooting, PDF page 162. Official manual (PDF). Fault numbers and names can differ between firmware versions.