Strings and inverter

Choose the panel, the inverter and the site's minimum temperature — the calculator shows the allowed number of panels per string and checks your choice.

Panel sizeInverterAbsolute minimum air temperature of the site, °C (empty — the minimum of the site's climatic region per ДСТУ-Н Б В.1.1-27; no location — U_oc max = 1.2·U_oc)

Panels per stringfrom 5 to 8

Panel Voc in frost59.9 V

Panel Vmp in heat35.5 V

Input MPPT150–425 V

Input maximum voltage500 V

Your string, panels

Open in the designer

How it is calculated

Open-circuit voltage rises in frost. Per HD 60364-7-712 (Annex B): U_oc max = U_oc·(1 + α·(T_min − 25)/100), T_min being the site's absolute minimum air temperature and α the panel coefficient; with T_min or α unknown — 1.2·U_oc. A string must stay below the input's maximum voltage; the operating voltage with hot cells must stay within the MPPT window; the winter upper MPPT limit and the input current are checked too.

The calculation is preliminary. A qualified engineer must check it before installation. Codes: DBN V.1.2-2:2006 (Ukraine) and the Eurocode; for other countries — snow and wind values from the national annex, entered by hand.