What happens when solar panels are connected in series?

In series, solar panel voltages add while current stays the same as one panel.

What happens when solar panels are connected in parallel?

In parallel, solar panel currents add while voltage stays the same as one panel.

Solar Panel Series and Parallel Calculator | PV Array Voltage & Current

Solar Panel Series and Parallel Calculator

Calculate PV array voltage, current and power for solar panels connected in series, parallel, or series-parallel combinations.

☀️ Field Rule: In series, voltage adds and current stays the same. In parallel, current adds and voltage stays the same. After this page, check voltage safety with the Solar String Sizing Calculator, choose controller size with the MPPT Charge Controller Calculator, estimate storage with the Solar Battery Bank Calculator, and estimate production with the Solar Panel Output Calculator.

🔆 PV Panels in Series and Parallel

Panel Power

Panel Vmp

Panel Imp

Panel Voc

Panel Isc

Panels in Series

Parallel Strings

System Loss Optional

Result Mode

Use panel datasheet STC values. For inverter safety, use the calculated array Voc with the Solar String Sizing Calculator because cold temperature can increase Voc.

Presets:4 × 450W10S2P 540W12S4P 550W

Number of Panels

Panel Vmp

Panel Imp

Panel Voc

Panel Isc

📐 Formula Reference

Series Wiring

Array Vmp = panel Vmp × series count
Array Voc = panel Voc × series count
Current stays same per string

Parallel Wiring

Array Imp = panel Imp × parallel strings
Array Isc = panel Isc × parallel strings
Voltage stays same per string

Array Power

Total panels = series × parallel
Array watts = panel watts × total panels

Loss Estimate

Usable watts ≈ STC watts × (1 - loss%/100)
Loss includes heat, dirt, cable and mismatch.

📋 Quick Reference

Series

Voltageadds

Currentsame

Best forhigher MPPT V

Parallel

Voltagesame

Currentadds

Best forhigher current

Check Next

String voltageinverter

Controller ampsMPPT

Cable/fusesafety

📚 Engineering Notes

Series increases voltageSeries connection is useful when the inverter or MPPT controller needs a higher input voltage range.

Parallel increases currentParallel strings increase array current, so cable size, fuses and controller input current must be checked carefully.

Check cold Voc before final wiringUse the Solar String Sizing Calculator to ensure cold-weather Voc does not exceed inverter or MPPT max input voltage.

Complete the solar workflowAfter this, use the MPPT Charge Controller Calculator, Solar Battery Bank Calculator and Solar Panel Output Calculator.

What is a Solar Panel Series and Parallel Calculator?

A solar panel series and parallel calculator helps estimate PV array voltage, current and wattage when panels are connected in series strings and parallel strings. It is useful for solar installers, technicians, off-grid system builders and DIY users.

Solar panels in series

When solar panels are connected in series, voltage adds while current remains the same as one panel. This is commonly used to reach the inverter or MPPT operating voltage range. After calculating series voltage here, verify safe cold-weather voltage with the Solar String Sizing Calculator.

Solar panels in parallel

When solar panels are connected in parallel, current adds while voltage remains the same as one string. This increases current, so cable size, fuse rating and MPPT input current must be checked. Use the MPPT Charge Controller Calculator to size the controller.

Related solar design workflow

Use this tool with the Solar String Sizing Calculator, MPPT Charge Controller Calculator, Solar Battery Bank Calculator and Solar Panel Output Calculator to build a complete solar sizing workflow.

❓ Frequently Asked Questions

Yes. In series, Vmp and Voc add, while current stays the same as one panel.

Yes. In parallel, Imp and Isc add, while voltage stays the same as one string.

Mixing different panels can cause mismatch losses. Series strings should use similar current panels, and parallel strings should use similar voltage strings.