- Error code
- W001
- Category
- Low DC voltage
- Manufacturer
- ABB / FIMER
1What the error means
The input voltage from the PV generator is below the start-up threshold. The inverter waits for the voltage to rise before it starts feeding in.
On the display or in the monitoring software it appears as Sun Low.
2Possible causes
- Low solar irradiance — morning, evening or overcast
- Shading or soiling of the modules
- Broken DC cable or faulty string
- DC switch open
3What to do
- If it appears only at the start and end of the day, it is normal.
- Check that the DC switch is closed.
- Measure voltage and current on each string in sunshine.
- Check for shading, dirty modules and damaged DC connectors.
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.