Battery Brain Fart!!

[pameridan04]

Catchy title huh..

Anyway I started to get cabin fever so I decided to take a ride over to the my coach stored in a U-Store it complex about 5 miles from my home.

I haven't been there in almost two months and I knew from my previous visit when I tried to unlock the coach with my remote that the engine batteries were just about dead.

Anyway after playing with a solar charger on deer feeders up North, I decided to see what is available for 12 volt engine batteries.

First I went on-line and did a search. My search took me to Harbor Freight aka Chicago Electric. I found a 5 watt Solar Panel Model 41122 on sale for $49.00..

I read about 30 reviews on this item and they were all very positive. Many of the reviews the people were using it to charge RV batteries. So I figured what the heck, its Saturday and I am bored anyway.

I went to HF and bought the unit. It comes with a 12 ft power cord to reach the battery. I was trying to think where was the battery compartment on my Meridan 36G was in comparison to my bedroom window. I really didn't want to stick this thing on my RV roof outside in the weather. But That is what many of the users did in the reviews.

Anyway, what a perfect setup. This will apply to Winnies & Itascas with the 36G Freightliner chassie. The solar panel is 12"WX 18"LX1"H. It fits perfect inside on the bedroom window ledge mid-window. Just set it there. The window has a small screen at the bottom, pop the screen open at the top, open the window bottom a crack, pull the battery connectors through, close the window, the wire will fit between the window nicely. Then pull out battery compartment, it is directly below the window. Open it up and connect to the main battey bank. I have two engine batteries. Your done, 5 minutes work.

I just connected the posivite connection and the negative connection to the front battery, I assume this is correct? Both batteries have a posivite & negative connector, connecting both batteries in line to their perspective terminal post.

I tried jump starting the caoch with my car battery to no avail. The engine gave a few turns then died. And yes I was using my house batteries as a booster.

One question I have for the experts is that is 5 watts enough to charge the two 12 volt batteries in the coach? On this set up you could easily add another solar panel. Just stand it on the window ledge with the 12 in side standing up. You could have one 5 watt solar panel for each 12 volt battery. But I don't know if this is necessary?

Just wanted to pass this along, I am hoping it will charge my two batteries enough that when I go back and try and jump start it again it will fire up. I have to sealed Duralast batteries. The pink sticker says 2/09...

Regards.... Jim P.

[Tha_Rooster]

No way!!! You can pull as much as 20 amps charging batteries. 5watts may keep full batteries top off with out any drain but that about all.

[GaryKD]

Hi pameridan04,
The 5 WATT solar charger is for maintenance only. To charge, you'll need an actual battery charger. I'd make a recommendation, but based on the OP, I do not think you have access to 120 VAC at the storage lot.

[SVTotem]

If power is not available for a charger at your storage space you might consider a booster battery from Walmart. You charge it at home and take it to the rig to provide a jump-start. Then use the engine to complete the charge. The solar charger might then help maintain the charge.

I am not sure you will get enough energy using the panel in the bedroom. The rating of the panel is for direct sunlight at an optimum sun angle. Your bedroom window is probably tinted and direct sunlight would only be available for a short time each day the panel is probably rated for outdoor use.

Try to get to the coach more often to run the engine and get the charge up. Deep discharge like this will significantly reduce battery life.

Best of luck.

[wa8yxm]

Quote:

Originally Posted by Tha_Rooster No way!!! You can pull as much as 20 amps charging batteries. 5watts may keep full batteries top off with out any drain but that about all.

Warning 2: That 5 watt Harb or Freight panel.. I do not think it has a diode in it.. So it runs them down after dark.

[pameridan04]

Correct I have no power at the storage site. I was using my jumper cables from my car and still couldn't get my coach started. I plan on buying new batteries anyway, but thought the solar panel would at least keep the new batteries topped off when I do buy them.

If it won't charge them then I was just hoping that the Solar panel would keep them from dying completely now.

The engine battery was showing 12.2 amps on the gage at control panel. The house batteries was showing 13.4 amps.

I look at this way, right now I have nothing to loose.

Regards Jim P.

[Midniteoyl]

Quote:

I tried jump starting the caoch with my car battery to no avail. The engine gave a few turns then died. And yes I was using my house batteries as a booster.

Your car batt/alt setup is not enough to start the rig on its own, BUT, if you hook up the cables from car to the main batt and set your car to run between 1500-2000 RPMs for about 10-15 mins (longer is better), it should charge the rig's batts enough that they along with your car's batt will start it... you need to keep the car running with the RPM's up while starting too, so bring someone with you.

[dc8cappie]

Tried to start the genset, charge up the house batteries, try the aux start switch to start the coach.

[OldChief7155]

Disconnect all neg battery cables when parking more than a few days. The dash switch willNOT keep the parasitic loads from draining them.

Also, to jump let it sit while jumpers are hooked up for a few minutes with the jumping vehicle revved up some.

[RTegarini]

On my motorhome, there is a lot of parasite drain, including the electric step and all the slides, which was always draining my chassis battery at about the 30-day mark. I installed a BEP Marine Battery Disconnect Switch off the 'positive' side of the battery. Most people install it on the 'negative' side of the battery, but I was told that any parasite draw could continue if that item was chassis-grounded, and that installing it on the 'positive' side takes the entire circuit out. I'm no electrician, so I can't say that is correct, but so far, it seems to have resolved the dead battery issue from sitting too long. -RT

[bluepill]

5 watts equals less than 1/2 amp. in a 12 volt system. And that's at maximum possible output in direct sun. Even that is barely enough to maintain a single fully charged battery that is disconnected and has nothing drawing current from it.

My MH came from the factory with a 10 watt panel on the roof, and stored out in the open sun it doesn't even maintain my disconnected 3 battery house bank.

IMO, 15 watts per battery is the minimum that would be worthwhile. Remember, it's only charging during the day, and not at full power in the early AM and late PM. So 15 watts is roughly equal to 1/2 amp. of full-time battery charger.

[Ray,IN]

Jump-starting a DP is not even close to doing so for a gas engine. One auto 12V battery hasn't enough cranking amps for a DP, and low amperage kills a starter rapidly. If you don't have access to 120VAC at the storage lot, you might think about renting a 2000W genset to power a 15/20 ADC charge-rate, 120VAC powered battery charger to recharge the batteries. Lot of trouble and some money I know, but the alternative is removing the batteries and taking them home for recharging.

[Senior Chief]

Doesn't this rig have a generator? What about just cranking up the gennie and plugging in a good battery charger set on Fast?

[Midniteoyl]

That would work.... so would allowing your car/truck to charge through jumper cables...

Not really hard thing, here...