Thor Forums

[Peterrrr]

Originally Posted by Lillardt

Thanks for such a detailed reply. Currently I'm just trying to find a solution to keeping my Ford engine and RV house batteries charged while in storage. I currently have a 6 watt Coleman solar panel directly wired to my house battery and a 2 watt Coleman solar trickle charger directly to the 12 volt hot plug on the dash for the engine battery. However, when I check the charge level on the panel in the motor home - my hook-up isn't keeping the batteries charged. Over a couple days I'm losing charge. Any suggestions?

As you have stated, 6 watts is not enough to keep up with the draw and loss of AHs out of your battery while it is in storage, even though they advertise the panels to do it. If you look at the specs the 6 watts and 400Mah is the maximum. This is an ideal which really never happens. It doesn't take into account the placement of the panel, the time of the year(where the sun is in the sky), location, temperature, shading, wire loss, etc. Besides the previously mentioned parasitic loads you would even have the battery's own self discharge. For a wet cell battery this can be as high as 10% per month.

I gather I am lucky that I have always had power available for the storage of my RVs. Not being aware of your storage location, the location may not be ideal for you to harvest the energy. Basically you would need more watts of panel and a charge controller if the location allows it.