To determine the size of the solar controller you need, divide the total watts of your solar array by the voltage of your battery bank.
How to Size a Solar Charge Controller: Step-by-Step Guide - Solar Panel Installation, Mounting, Settings, and Repair. To size a solar charge controller, you first need to determine the amount of current your solar panels produce, measured in amps, and your battery bank's voltage.
Depending on the number and power of the solar panels to be paired with the number and voltage of the battery bank, a selection of the best size charge controller can be made. Charge controllers are rated according to amperage.
Charge controllers are sized depending on your solar array's current and the solar system's voltage. You typically want to make sure you have a charge controller that is large enough to handle the amount of power and current produced by your panels. Typically, charge controllers come in 12, 24 and 48 volts.
How many volts does a solar charge controller have?
Typically, charge controllers come in 12, 24 and 48 volts. Amperage ratings can be between one and 60 amps and voltage ratings from six to 60 volts. If you haven't sized your system yet or calculated your energy needs, we recommend using the Renogy solar power calculator.
Higher voltages often mean you can manage with a smaller controller, but it's essential to do the math to be sure. Solar panels come in a variety of wattages. From small 100W panels suitable for basic needs to massive 1200W panels for larger installations, the wattage directly impacts the size of the controller you'll need.
Assuming 140W of panels and 1,088Ah of 12V storage, you should be charging with at least 60-70A. 140W will get you 10-ish. If you want to spend $1000 on a charge controller go right ahead. You can add charge controllers to the same battery attached to separate arrays as well.