Disclaimer: This content is for informational and educational purposes only. The diagnostic steps described are suggestions, not an official service manual.
Phenomenon: The inverter displays Error 122 on the screen, with the fault LED illuminated. Inverter shuts down or fails to operate normally.
Technical Causes:
- Internal DC bus voltage outside permissible range (too high or abnormal).
- Potential hardware issue in boost circuit, capacitors, or control board.
Diagnostic Procedure:
- Fully power cycle the inverter: Disconnect AC and DC supplies, wait 10 minutes, then reconnect.
- Observe if the error clears and monitor bus voltage via advanced diagnostics if available.
Resolution:
- If error clears intermittently, monitor system closely.
- Persistent error indicates internal hardware fault; no field repair possible.
WARNING: Maintenance and repair of PV systems, high-voltage DC, and AC components must only be performed by certified professionals with valid electrical qualifications (e.g., SEP/G1 in Poland, or local European equivalents). Unauthorized opening of the inverter housing will void the warranty and carries a risk of electric shock or fire.
In case of persistent hardware failure, the only authorized path for repair is contacting the official Growatt Service Department.