What is Solar String Sizing?
String sizing determines how many panels to connect in series (one string) and how many strings to connect in parallel so that voltage and current stay within the inverter's safe operating range.
Key Rules
- Max voltage check: String Voc at the coldest temperature must never exceed inverter max DC voltage
- MPPT range check: String Vmp at operating temperature must fall within inverter MPPT window
- Current check: Total parallel strings × Isc must not exceed inverter max DC current
Note: In Indian conditions, use the coldest recorded winter temperature for your city (typically 5–15°C) to calculate worst-case Voc. Panel voltage rises ~0.3%/°C as temperature falls.