Solar Battery Maintainer

[Ron]

My wife and I have had a 32' class A for a little over a year now and have so far just taken short trips around California. Our longest trip was to Portland Oregon (about 600 miles) but mostly just short 3 day trips.

My main interest in solar is to keep my batteries maintained while the rig is in storage since there is no power out there. It is stored outside and we use a cover to keep the sun rays off so any solar panel will have to be outside of the cover. This makes a permanent installation onto the roof not doable unless we cut a hole in the cover to let the sunlight through, which I don't want to do.

I know they sell small battery maintenance panels in the 5-15watt range but I get concerned about overcharging the batteries since these battery maintainers don't normally have charge controllers on them. I'm thinking, why not just get a 100W solar panel like the Renogy 100W starter kit (Amazon) and figure out some way to make a portable mount that can be installed on top of (or outside) our RV cover. It would have to be secured some way so that wind doesn't cause it to rub against the cover or the motorhome.

The added bonus is that it could also be used while camping.

Has anyone done something like this?

[blw2]

lots of folks have....

I store mine in a lot away from the house too, and when we first got it I studied a good bit on doing something like this, vs the little maintainer panels.

In the end, I installed battery disconnect switches right at the batter lug, one for the chassis battery and one for the house.

So far so good. i store it with the batteries basically fully charged, and with no parasitic loads to worry with, they have so far held up considering the most it ever sits is 4-6 weeks.

[Beacher]

I have been using a solar panel BatteryMINDer Model SCC-015 for over six years. I originally purchased it to maintain one 12v Trojan Deep Cycle battery on my PopUp.

For the past year it has been maintaining the charge on the motorhome batteries, or my Ford Expedition, (whichever is being uused less).

Besides including a charge controller, it also desulphates any batteries that
were not well maintained to begin with.

[Ron]

Blw2, I also have installed a manual battery disconnect on my chassis (engine) battery and rely on the factory disconnect for my coach (house) battery. I'm not aware that there will be any loads on the house battery with the disconnect switch open. I could be wrong though. I still worry about extended periods with no maintenance charge. I have been using our MH every 4-6 weeks but the current down period will be 8 weeks between trips. 😟

[Ron]

Beacher, thanks for the info on the Battery Minder. I think at least the controller part is something I will get. It says it works with all brands of panels so I might get a little larger 100W panel. The BatteryMinder controller is good for 180W. I like the remote panel for viewing Battery status. It says it will charge up to 4 batteries. Do you know if it monitors the batteries separately or together as a group?

Worst case situation, I can use a Trik-L-Start engine battery maintainer which will charge and monitor the engine battery separately using whatever charge the house batteries are getting.

[Ron]

Beacher, do you have your panel hard mounted on your rig? Or is it temporary? Most of my question has to do with wanting a solar panel and wanting to cover my MH while in storage. I haven't seen a post addressing this situation yet. Hard mounting panels to my roof won't really do much good after the cover goes on but that's when I want the battery maintenance.

I was thinking about maybe a PVC mount that spans across my roof (on top of the cover) with a solar panel mounted on it and then the mount can be tied under the coach once the cover is in place.

Has anyone done something like this?

[jrben]

This may be a dumb question, but the BatteryMINDer says it works with up to 4 12v batteries. My house batteries are 6v. Is there a solar option for 6 volt batteries or can the 12volt version be used?

[Beacher]

Originally Posted by Ron

Beacher, do you have your panel hard mounted on your rig? Or is it temporary?...?

It's temporary. It sits on the dash, facing out from the windshield. It maintains the battery very well without direct sun all day.

[Ron]

JRBEN, your 6 volt batteries are no doubt wired in series to supply 12 volts to your rig. You can charge them with a 12 volt battery minder or with a 12 volt solar setup by charging them in series as well.

[Ron]

Beacher, I built a PVC solar panel stand to sit on top of my RV cover for when it is in storage. I'm going to test the whole system this coming weekend. I'll post pictures when it is all hooked up. I tested the system last weekend using the battery in my car. It seemed like it was working but my car battery was already pretty well charged. I tried turning on the headlights to see if I could get more amps going from the solar panel (and charge controller) to the battery but it didn't really register anything on the charge controller meter. The volts started at over 14 and then quickly tapered to 13.8 but the amps said zero. I'm not sure why.

[Ron]

This is the solar panel I decided to go with. It's a Renology 100watt panel from Amazon

Solar Panel 2-500.jpg


I built a PVC frame to tilt it up 15% and strapped it on top of my MH. While in storage, I put the panel (with it's PVC frame) on top of the cover and on top of the A/C unit. We had some pretty strong winds last month and it didn't budge at all. It works great!

Solar Panel 1-500.jpg

I used the Morningstar SunSaver controller because it will charge two battery banks independently of each other. It has a remote monitor for inside the MoHo.

Solar Controller 1-500.jpg


The SunSaver Monitor is on the right. The left meter is a Bogart Trimetric Battery monitor. It records the history of the battery state for 5 days and also 5 charge cycles in the past. The SunSaver does an excellent job of maintaining the batteries!

Trimetric 1-500.jpg