Solar charge controller is a regulator that controls the charge and discharge current of solar battery. It is essential to prevent overcharging or over-discharging a battery. Then can prolong the battery's life span.
But many people don't know how to choose a solar controller, Here we will figure out how to calculate a controller size.
First, calculate the total watts of the solar array. Then divide it by your battery bank's voltage to get amps, add 25% to allow for cold temperatures and as always.
For example: 4 pcs 100 watt solar panels in series = 400 watts / 12 VDC battery bank + 25% = 41.6amps. You would choose a 50 amp, 12 V Solar charge controller in this example.
Note; These examples are simple calculation, usually suitable for small solar system, if your system is big with multiple strings, then you can contact us for more professional opinions.