How to hook up a solar charger to a 2 battery system

[v12mac]

I would like to hook up a solar charger to keep a maintenance charge in a 2 battery set-up. How can I wire this so that it charges both batteries but doesn’t cause juice to flow from one to the other? <br /><br />Mac

 

[Luna Sea]

Re: How to hook up a solar charger to a 2 battery system

I have a solar charger I'll be hooking up soon. And I have a 2 battery system. Only thing I can think of if you want it "hard wired" is to send it to a battery switch and then select "one" or "two" or "both". I'd stay away from the "both" though. Those chargers don't put out much anyways. I don't know your setup but if you only have one engine, like I do, the "starting" battery is always turned "off" when I leave the boat, the accessory battery runs the pump and anything else. So my starting battery never needs charging anyways

 

[ThomWV]

Re: How to hook up a solar charger to a 2 battery system

Well, I'm sure there is some sort of isolator that someone is selling to do that but in fact all you'd need to do is run the negative from the solar panel to the same place that your current negative jumper cable between the batterys is and then split the line on the positive side and put a diode (what capacity i do not know) in each line so the two battery couldn't sort of cross-talk at night when the charger wasn't exceeding either of their current voltage capacities. Anyway look for a device called an isolator and you can use it to segregate the two batterys.<br /><br />Thom

 

[islandboat]

Re: How to hook up a solar charger to a 2 battery system

You may want to buy 2 solor chargers since some of them are fairly inexpensive. Charging 2 batteries with a small solor charger (or any small battery charger) may not effectively charge both batteries if they are of different capacities. We use solor chargers on our company trailer brake batteries to keep them reasonably charged while sitting for long periods. These are small batteries and the chargers are actually decalsifiers. Hope I spelled that right. They are called solor chargers by habit but they really only protect against the internal plates calsifying. <br />Back to using only one charger. Perhaps you could install a diode in each wire between the charger and positive post on each battery.