Community Forums

Doc Sarvis · 09-27-2022, 09:21 AM

I am trying to become more battery literate.

I have a 170w panel on the roof connected to a Zamp controller. Currently have the two wet Interstate batteries that came with the 22FQS.

When I store the trailer I turn off the main switch to kill any parasitic losses.

I leave the panel plugged to the roof port and I leave the batteries in the trailer and hooked up.

My assumption is that the controller is doing what is needed to monitor the battery health. FYI I am in Southern Cal so no issues with lack of juice from the panel.

Are my assumptions okay? Or am I damaging the batteries?

Iceclimber · 09-27-2022, 10:20 AM

I suggest that with a solar controller, you should be fine. I am assuming it's capable enough to float your batteries but perhaps post the controller model to be sure. Then you just have to keep water in the batteries and bob is your uncle.

Mark_K5LXP · 09-27-2022, 10:29 AM

The only assumption I wouldn't make is whether your "main switch" really is. Once I verified through measurement that the batteries actually are disconnected, then I would entrust the controller to properly maintain the batteries.

Mark B.
Albuquerque, NM

JHinman · 09-27-2022, 12:10 PM

Sounds like the same setup I had on my ORV. My controller was a 30 amp PWM. If your panel is getting good sun (no roof) you should be good.

The kill switch may not disconnect everything, but your panel should take care of anything that is not shut off.

In my current rig I still had a draw of about 0.05 amps with the switch off. I never could find the culprit.

Get a Victron BMV-712 and set the current threshold to 0.01 or 0.0 amps to see what actually happens.

Passin Thru2 · 09-27-2022, 12:12 PM

In my 22FQS the wiring from the solar panels/controller does not go through the main DC switch. Even with the switch in the off position the batteries will charge.

I added a switch between the panels and the controller so I could switch off the solar charge to the batteries in the winter and while I am working on the batteries. I have BB lithiums and they recommend that to store the batteries in the winter to charge them fully and then disconnect them from the system. They will hold the charge for a year.

I also added a circuit breaker between the controller and the batteries for safety purposes. I can also use that to eliminate any parasite draw from the batteries back to the controller when I have the main DC switch off and the solar panel switch off.

Not pertinent to this thread but I also switched out the Zamp controller for a Victron MPPT controller for more control. I mounted the the Victron, the solar panel switch and the circuit breaker in the locker above the bed behind where the Zamp had been mounted.