- Error code
- 7703
- Category
- Self-diagnosis
- Manufacturer
- SMA
- Models
- Sunny Tripower (STP)
1What the error means
A code from the 7701–7703 group: the grid relay test failed. Before connecting to the grid the inverter checks that the relays open and close correctly — if the test fails, it does not connect.
2Possible causes
- Stuck or burnt relay contacts
- Fault in the relay drive circuit
- Problem with the voltage measurement on either side of the relay
3What to do
- One restart, with AC and DC switched off for 2–3 minutes.
- If it returns, the relays need to be replaced in our lab.
4Repair by Aineas
You send the inverter to our lab in Thessaloniki. We diagnose it, inform you of the fault and the cost, and the repair starts only after you approve it. Every inverter is tested under simulated operating conditions before delivery.