212QBW Solar Install Questions

[GHen]

If I remember right, there was a loop of red wires from the roof, two still connected.
There was also a black and red coming up the wall from the batteries.

Cut the loop and connect to the solar side of controller. Connect the red and black to the battery side of the controller.

My rig was “wired for solar” and had sticker on the wall from “Go Power”

[Mudbug]

Thank you very much, GHen. I have been nervous about cutting that exploratory hole in the wall. Had already added an SAE Solar plug to my batteries, for my 120W briefcase panel. I will pursue installing panels on the roof shortly. Again, thank you.

[damaltor]

Originally Posted by Mudbug

So, back to my original problem…
I have the Solar gland on the roof. The sticker on the wall where controller will go. Batteries hooked up and charged.
I tested the wires from the gland, NOTHING. Shouldn’t I get 12vdc ?

I placed a Solar panel with a controller installed, the attached it to the gland, NOTHING. Huh ?

Are the wires cut inside the wall ? Or not connected to the battery ?

The wires to the roof (gland) should not be connected directly to the battery, they should run to the wall where the sticker is and connected to a controller there. Then the controller will also be connected there directly to the battery.
So if you have a panel connected on the roof and you test the wires where the sticker is, you should see voltage from the panel and see voltage from the battery there. The wires should NOT be connected directly from the roof to the battery.
It would be wise also to wire in a switch of sorts from the roof to the controller, so you can isolate the panels, should you need to disconnect your battery(s). Most controllers may be damaged having voltage from the panels and not being connected to the batteries first.

[GHen]

One more item to consider, the only solar charge controllers I have seen for the hole in the wall you cut are PWM controller. That’s what I have. They work ok as a starter system but a MPPT controller is much better if you add a few more panels.

Others may have more info, but here is a little basic info on the difference.
Solar panels are not 12v, they can be 18v or even 24v. They are still sold as 12 volt panels. A PWM controller takes the first 13-14 volts and uses the amps from that voltage to charge the batteries. That extra voltage and amps (between the 14v and 18v) is wasted. A MPPT controller takes that extra voltage and also converts it to use to charge the batteries. So you get another amp or two charging the batteries.

That also means you can connect the solar panels in series on the roof. So, you connect 2 18v panels together to make 36volts and then you can use use smaller wires down to the controller. OR, it also means you can connect more panels down to the controller using using that same light weight wire installed at the factory. The higher the voltage the easier it is for the wires to carry the amps down to the controller.
I hope that makes sense. And for the solar experts here, I hope I explained it in a easily understood way, even though it’s more complex that what I said.