Since off-grid solar panels are usually setup for 12 volt charging system, if you have a 24 volt battery system, you will need to wire two panels in series, or get a single high voltage solar panel, in order to generate enough voltage to charge a 24V battery.
Here’s a step-by-step guide on how to wire solar panels in parallel for a 24V solar system: Gather the necessary materials including MC4 connectors and the appropriate length of solar PV cables to connect the panels to the charge controller. Identify the positive and negative terminals which are typically marked with a red and black wire or symbol.
This can be done either by using 24V solar panels and connecting them in parallel (since this leaves voltage alone) or by connecting sets of two 12V solar panels in series (since this will double the voltage to 24V) and everything else in parallel.
If you’re planning to wire a 12V system in parallel, download our solar panel wiring diagram PDF below. If you’re using a 24V battery bank and a 24V inverter, you’ll want to bring your solar panel voltage up to 24V as well.
To wire a solar charge controller, firstly, connect the battery to the controller, ensuring the positive and negative terminals are correctly matched. Next, connect the solar panel to the controller, again matching the terminals correctly. Always make sure everything is safely disconnected from power sources while working.
For example, wiring two 12V solar panels in series produces 24V, three 12V panels produce 36V, and so on. 24V panels can also be combined to hit the target system voltage. Follow these steps to connect solar panels in series: Use MC4 branch connector cables or 10-12 AWG copper wire to link the panels. Prepare weather-proof connections.