- Error code
- 3501
- Category
- Insulation fault
- Manufacturer
- SMA
- Models
- Sunny Tripower (STP)
1What the error means
Error 3501 indicates that the inverter has detected a ground fault in the PV generator or that the insulation resistance (R-Iso) is too low. Possible causes are damaged PV modules, DC cables or PV connectors. First, the voltage between the positive conductor and ground, as well as between the negative conductor and ground, should be measured. If the voltage shown on the multimeter keeps decreasing, there is no leakage in the cables. Another method, where possible, is to move the strings of the inverter that has the problem to a neighbouring inverter. If they operate normally, the problem lies in the inverter and not in the installation.
The SMA error 3501 fault is a fault that our lab has repaired with a 100% success rate.
Once the inverter has been shipped to our lab, the diagnosis is carried out with the diagnostic machine.
The customer is then informed of the cost of repairing fault 3501.
Once the inverter has been repaired, it is tested on modern switching power supplies with Solar array simulator software and it is verified that the MPPT efficiency is above 97%.
This is done to make sure that the inverter will operate at 100% without losing a single kWh of production.
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SMA Error 3501
2What to do
- Note the code and the inverter model (nameplate on the side of the unit).
- Switch off the grid (AC) breaker and switch it on again after 2–3 minutes.
- If the error returns or keeps recurring, do not keep restarting the unit — contact us for a diagnosis.
3Repair 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.