I've got a portable 20 watt solar panel which I bought with a view of leaving it plugged into the van during periods of non-use to keep my battery charged. But how should I connect this? Do I need a control unit to ensure the battery is not charged too much, and the solar panel doesn't drain the battery during the dark hours? Is there a recognised method of installing this charging system?
I would invest in a small regulator, very cheap on ebay. Then put a long cable on it so the panel can be mounted out of the way in the sun pointing up. Then you can cover the van or park it in the shade. A pair of alligator clips on the lead from the regulator to put on the battery.
If you want to spend a few dollars more, then get a regulator which has two stages(or 3). That is charging and float. The float charging mode at a lower voltage eg 13.8V is better for the long term health of the battery. 20 watts is less than 2 amps.
Thanks for that, I have done as you suggested. I bought a pretty clever controller, and I'm also going to put a panel of the roof ( having found to my surprise that the van in wired for but not with solars!)
For now I've run a cable from the controller to an Anderson plug at the front of the van, and can now have my solar panel in the sun on a lead plugged into the Anderson.
Hmmm, I tried it on my van twice, by plugging the panel into the Anderson at the front, and it seemed to run the battery flat, hence my post.
Hi DBH
Well all I can say is the setup is wrong. What is wrong is hard to say from my computer keyboard Perhaps you have the connections back to front and instead of charging the battery, the panel is discharging it ?? Be the first thing to check most likely.
If not that, then I guess get someone who can check it all out with a meter, as it should work OK. Something is wrong !
Have you a multi meter in your possession? Set ti on the 20 V range, work your way along the chain from the panel to the battery and check you have not transposed any of the wiring.
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PeterD Nissan Navara D23 diesel auto, Spaceland pop-top Retired radio and electronics technician. NSW Central Coast.
Perhaps you have the connections back to front and instead of charging the battery, the panel is discharging it ?? Be the first thing to check most likely.
