Cause -
- input voltage low/missing
- Polarity reversed
- Main board damaged
Solution -
- Test - DC switch off
- Check PV connections
- Check polarity
- Check voltage > 120V Single, >350V three
- Test - DC switch ON
- Check voltage > 120V Single, > 350V three
- If DC voltage is "0" replace inverter
Troubleshooting - Inverter is not receiving signal from DSP or a power board may be broken. Check the DSP signal interface and power board for any equipment faults.