What is string sizing in solar?

String sizing determines how many solar panels to connect in series (a string) and how many strings to connect in parallel to match your inverter's voltage and current input range.

How many panels in a string for a 5 kW inverter?

For a typical 5kW inverter with 550V max input and 400W panels (Voc ~49V), you can connect 9–10 panels in series per string.

Why does string sizing matter?

Incorrect string sizing can damage the inverter if voltage is too high, or reduce output if voltage is too low to reach MPPT range.

Solar String Sizing Calculator India 2026

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.

Solar String Sizing Calculator

Panel Specifications

Inverter Specifications

String Options (Series Panels)

Enter panel and inverter specs to calculate string configuration

What is Solar String Sizing?

Key Rules