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 125 on the screen, with the fault LED illuminated. Inverter operation halts.
Technical Causes:
- Internal hardware detection failure, often related to insulation monitoring circuit or control board anomaly.
- Potential damage to internal components.
Diagnostic Procedure:
- Power cycle the inverter: Disconnect DC and AC, wait 10 minutes, then reconnect.
- Observe if the error clears after restart.
Resolution:
- If the error clears temporarily but recurs, monitor system operation.
- Persistent error requires internal inspection.
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.