From the point of electrical parameters, the major parameters of solar controller contain the followings:

Charging current (Amp) and Charging voltage (Volt）

The charging current is subjected to the PV power rating, and ambient working temperature around the solar controller, the solar panel will provide the maximum output current (Isc), the rated current of solar controller must be beyond the maximum Isc of solar panel, additionally,

If the solar controller always works in an extreme environment with high ambient temperature, you must select solar controller with enough high rating, the solar controller’s rating must be at least 5~20% more than the solar panel.

For example: use a 250 watt 36 cell solar panel, the output voltage is 18Vdc maximum，the current delivers approximate 13.9Amaximum，usually, you can select a solar controller with rated 15Amp; If the solar controller is exposed under the direct sunlight or worked in a sealed environment, you’d better to select a solar controller with higher rating of 20Amp.

The charging voltage selection is subjected to your targeted battery, Powerprow offers solar controllers with single 12V version or 12/24V auto version. If your application is 24V system or you may have chance to use 24V battery, please consider our solar controller with 12/24V auto version, if you make sure your system just be 12V, please consider using our single 12V solar controller, which will obtain higher convert efficiency and lower dissipation.