Need Help Please: Wiring Up This Solar Panel As 12VDC Battery Charger

[sstephenson]

Hello all. I have no experience wiring solar panels, but I picked up this folding "suitcase-style" panel setup at a local Swap Meet (see images below). I can't find any information about it on the web. I'd like to hook it up to charge a 12VDC deep cycle marine battery. It looks to me like it may have some sort of controller wired-in on the back of the panel, but there is no digital readout of any kind. I checked the output voltage with a multimeter and it was producing 21 volts in full sun. I'd really appreciate it if someone can tell me exactly what I need to complete my 12VDC battery charger setup, and if there's anything I can add to show some sort of digital panel output reading, that would be great. Thanks!

 

[B52Bombardier1]

Buy an inexpensive solar charge controller from EBay and hook these panels up as an input to the charge controller. Hook your battery up as an output from the charge controller. Its pretty simple.

Rick

 

[sstephenson]

Thanks Rick!

 

[jamiereis]

A little late here but this could help someone in future.
This could be a huge post, but here are some high-level details that may help you avoid some pitfalls here.

1.) You have two monocrystaline panels that are wired together in parallel. We know this because you're outputting ~21v in full sun. If they were wired in series, you'd be outputting about twice that amount.
So, your Isc is 2x what is stated on your panels (3.24 x 2 amps = ~6.5 amps).

2.) You have an Anderson connector coming off of your panels, so you might want to wire up an Anderson connector to your charge controller so you can retain the portability of this and use it for other things when not camping.

I'd recommend an MPPT charge controller--you might want to consider getting something with a higher amp rating than you're currently going to be using so that you can expand the system if you decide to do-so later.
40 amp is overkill for your current setup, but typically is a good target for an RV solar setup. You could add four more 100w panels and still be covered.

This Renogy Rover 40 Amp 12V/24V DC Input MPPT Solar Charge Controller is on sale for $99, and is fine if it fits into the budget:

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Otherwise, this Allto Solar Intelligent 10A MPPT Solar Charge Controller will manage your current needs just fine and will save you some money at $39:

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For this, you'll need some Anderson to SAE adapters or will have to wire up to your components another way.

You should always connect power from your battery to your charge controller before connecting power from your PV array to your charge controller.
To do this, you should have DC switches or breakers on either end, or you can get away with a battery disconnect between your charge controller and battery.

You'll always disconnect in opposite order (PV first, then battery).

Good luck and glad to help if you have any specific questions.