Community Forums

NorCal27 · 07-12-2019, 10:52 AM

I have a 135 w solar panel, 2 12 volt deep cycle batteries (less then 1 year old full of water) 4kw generator. Arrived yesterday with a reading of 13.2 v output. Did not use hardly any electricity (no tv watching) and this am we had 11.9 v output. Ran generator 45 minutes, limited by generator run hours. Up to 12.4 now down to 12.0. We are in Glacier NP east with sunny and cloudy weather, but very long daylight hours. Can the solar panel be sucking up power instead of supplying. We are in a long trip and any major work will have to wait. What should my expectation be on coach power?

twinboat · 07-12-2019, 12:04 PM

Have you installed an inverter in your rig ?
Inverters draw from the batteries If left on. If the fridge is on inverter power, that will kill your batteries in 1/2 a day.

Have the 1 year old batteries gone dead a few times or froze ?
They need to be stored full charged.

Charging the batteries for 45 minutes doesn't help much. They need 3 to 4 hours if that low.

135 watts is putting, maybe 4 to 5 amps into them per hour. You may be using more then that.

With 2 batteries, you should do better then you are. See if something else is on, like compartment lights, radios, ......

NorCal27 · 07-12-2019, 12:34 PM

We have an inverter, but it is off. We live in a moderate climate. Propane refer. Looking for any light, but nothing. If I get to civilization I might get the coach batteries tested.

450Donn · 07-12-2019, 12:52 PM

Not enough solar, and definitely not enough battery. 12VDC are probsbly combo batteries, and simply do not last. Swapping to 4 golf cart batteries and adding more solar will cure your problems. With 250watts of solar and 4 golf carts I could easily go 4 days in cool weather even watching TV at night.

twinboat · 07-12-2019, 03:02 PM

I only have 2, 12 volt batteries, ( GP 31, 105 AH type ), and have dry camped overnight many times.

We use lights, inverter powered Sat. TV, and run a coffee maker in the morning. On more then one occasion, we have also run the furnace on the cooler nights.

The bateries are still strong enough to start the generator.

We do have 400 watts of solar but that doesn't do anything overnight.

If you can't get one night on your batteries, you don't need more batteries, something else is wrong.