Solar Tools

Solar Charge Controller (MPPT) Calculator

Enter your solar panel specs and battery bank and we'll size the right Victron SmartSolar MPPT controller — accounting for cold-weather voltage rise, charge current, and PV fusing. Then we can install it on your RV, van, or boat.

Pick your panel

Panel model Choose a panel to auto-fill its specs, or enter them manually below

Your solar panel

Panel wattage (W) Panel Voc (V) Open-circuit voltage, on the panel's label

Panel Isc (A) Short-circuit current on the label (optional) Battery bank voltage

Array wiring

Panels in series Per string (adds voltage) Strings in parallel Adds current

Advanced — cold-weather derating

Coldest temperature (°F) Voc rises as it gets colder Voc temp coefficient (%/°C) From the panel datasheet

Enter your panel wattage and Voc to size your controller.

Sizing follows Victron's guidance (a 5V input buffer below the controller's max PV voltage) and NEC 690.8 (1.25× Isc fusing). Panel counts, shading, and wire runs are confirmed on-site — get an RV install estimate.