Voc and Isc calculator

Defaults: REC Alpha Pure-R 430 W (REC430AA PURE-R), manufacturer datasheet, US print UL EN 6.2025: Voc 59.7 V, Isc 8.91 A, Voc coefficient -0.24 %/K, Isc coefficient +0.04 %/K. The datasheet prints a cell count of 80 half-cut cells but not how they are wired; we assume all 80 in series. Irradiance only changes Voc through a modelled logarithmic term, so for cold string limits leave irradiance at 1000.

Cell temperature (°C)

Irradiance (W/m²)

Modules in series

Voltage limit (V)

Isc design factor

Module data (change to your datasheet)

Voc at STC (V)

Isc at STC (A)

Voc coefficient (%/K, negative)

Isc coefficient (%/K)

Cells in series

Diode ideality (about 1 to 1.5)

Design aid only. Check the limit, the design temperature and the current factor against your inverter manual, the adopted code and your AHJ.