Thursday, August 31, 2017

Early Morning Solar Musings

So I was laying in bed yesterday morning watching the sun come up and thinking how nice it was to have solar panels charging the motorhome batteries. And then I thought, "Wait a minute, it is plugged into the 30 amp outlet on the workshop. Does that mean the solar charging is bypassed by the 110 volt converter? Am I getting any benefit at all from the solar while I am plugged into shore power?".

I didn't know. So I went onto the Facebook RV Solar page and asked the experts and as usual, the answer is "It depends". It depends on how good a solar controller I have - mine is a lower end Pulse Width Modulated model and if it is programmable - no it is not. The consensus from the experts was that I was getting very little (if any) charging from the panels while I was plugged in. Well, that's not why I invested several hundred dollars into the 325 watt system of three panels, four batteries and a controller.

I was advised to turn off the breaker powering the converter. This would turn the charging duties over to the solar converter while still leaving the rig plugged in and the wall outlets powered. The best of both worlds.

I opened up the breaker panel and there it was, breaker #2 clearly labeled, "Converter". I turned it off and watched my battery voltage drop from 13.7 volts to 13.6 as the solar accepted the load. A few minutes it was at 13.8! It was working even in the overcast condition we then had. Now I just have to monitor the voltage to make sure it keeps up.

Thursday morning EDIT: This morning under a bright sky it was equalizing at 14.8 volts! I am a happy camper!!

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  1. Since you guys helped install my solar, I haven´t plugged into the 30 amp outlet I have here at home. I clean the panel occasionally, check the water level in the batteries, and turn 12V items such as the Fantastic fan and let them use up the juice.

    Next house will be solar.

  2. A friend of mine in Las Angeles has a completely solar house. Maybe Don will add something here. What are the details Don and what are your summer / winter electric bills?

  3. Good choice to let the solar do it's job, with our controller we get a full solar charge even when plugged in 14.8 volts as well.

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