Old Hand Fault Finder

Yaskawa GA500 CE: Modbus Communication Error

What it means Modbus communication with the drive failed.

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

Likely causes

  • Wrong cable wiring
  • Shorted or disconnected cable
  • Electrical interference

Checks, in order

  1. Check and correct wiring
  2. Replace a damaged cable
  3. Reduce interference with shielded cable and good grounding

Source

Source (reworded, not copied): Yaskawa, GA500 Drive Maintenance & Troubleshooting Manual, TOEPYAIGA5001A, Faults, PDF page 44. Official manual (PDF). Fault numbers and names can differ between firmware versions.