Free tool
Solar string sizing calculator (panels per MPPT)
Temperature-corrected panels per string for safe inverter voltage limits.
Panels per string
4 – 10
Panels per string
4 – 10
Cold Voc per panel 46 V at -15°C
- Maximum panels per string
- 10
- Minimum panels per string
- 4
- String Voc at coldest temperature
- 459.8 V
- String Vmp when hot (60°C cells)
- 125 V
- Inverter voltage window
- 120 – 500 V
- Safety margin at max string
- 40.2 V
Cold-temperature Voc rise is the number that destroys inverters in Ghazni winters. Never exceed the maximum panels per string shown above.
Questions about this calculator
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