If you don’t have one of those or you built your own solar array, use a multimeter to measure the wattage output of your solar panel when it’s in the full sun. Solar panels are designed to produce more power than the voltage they’re rated for. For instance, a solar power designed for a 12V output might actually produce 17V of power. That’s because they’ll only produce their max voltage under ideal conditions. [2] X Research source If the solar panel produces more power than the battery can handle, the battery can overcharge and be damaged. A charge controller helps prevent this from occurring.

For example, if your solar panel is 300W and you want to charge a 12V battery, you’d divide 300 by 12 to get 25 amps. In that case, you’d get a charge controller rated for 30 amps.

These options are more expensive than PWM models, but the increased energy efficiency can quickly make up for the price difference.

It’s always safest to mount electrical equipment to a non-conductive material, like a PVC panel or a piece of wood, rather than installing it on a metal surface.

For instance, you may want to use a red wire as your hot wire and a black one for the negative, or you could use solid black wire for your negative and a black wire with words printed on it for the positive side. Of course, if your battery bank already has wires connected, you won’t need to attach new wires to the battery first.

Take care to match up the positive and negative cables with the appropriate ports, or you could short out your battery or controller. If you’re connecting a 12V battery, use 10-gauge or 16-gauge wire. [9] X Research source

You can find these connectors wherever electrical or solar supplies are sold, and they should come with specific instructions on how to attach them to the wires.

Be sure to connect the male connector to a female connector and vice versa. You can never be too careful when you’re working with electricity. Take the time to double-check that the positive and negative cables are matched up correctly!

Some charge connectors will even communicate with an app, so you can monitor the voltage from your smartphone or tablet!

Since the charge connector will stop the flow of energy to the battery once it’s charged, it’s fine to leave it on the charger until you need it!