Solar question - 12v versus 24v

24 volt input to the controller will reduce the voltage loss a tiny amount. Probably not worth the hour or so to make the wiring changes. In most cases, the 24 volt input will put in about 0.3 more amps per hour in full sun, not much of a change.

However if one panel is shaded, and only putting out say 2 amps, then this will limit the amps output of both panels. While in the 12 volt mode, one panel can be putting out the full 6 amp rating in full sun, and the panel shaded by a tree can put out 2 amps, thus you will have 8 amps total at 12 volts (96 watts), not 2 amps at 24 volts (48 watts).

So keep it the way it is, you will be better off when parked in partial shade - I think. . ..

Just have fun camping, and enjoy the extra power of the panels!

Fred.

Thanks guys. I appreciate the advice. Looks like I will stick with the current setup.

Phil

BFL13 wrote:
The controller is more efficient (more watts out for the watts into it, when not stepping down from 24 panel to 12v battery than doing 12-12, so yo would gain amperage there, but OTOH the higher panel voltage gives more room for the controller to do anything in lower light conditions when there is less wattage from the lower voltage coming in.

So it is possible one could be better than the other sometimes and the other way better other times.

Seems like you are getting good results now, so I agree---leave it be and enjoy your solar :)

I agree with BFL.


with your configuration I doubt there is enough of a noticeable difference that one has a distinct advantage over the other. Where the 24 (or 36 or 48V) series connection has an advantage is if the run is very long or current very very high.

In my case, I use portable panels, sometimes as far as 150ft from the trailer, using #10 wire. In this case series does win out in that I have 3 panels, so series has 1/3 the current, hence 1/3 the voltage drop between the panel and controller. But even in this case the difference is on the order of 10-15%, when running at max output current, noticeable, not a killer but worthwhile. Once batteries are near full charge, the advantage goes away anyway since current drops way down and is determined by the state of charge, not the panel.

The controller is more efficient (more watts out for the watts into it, when not stepping down from 24 panel to 12v battery than doing 12-12, so yo would gain amperage there, but OTOH the higher panel voltage gives more room for the controller to do anything in lower light conditions when there is less wattage from the lower voltage coming in.

So it is possible one could be better than the other sometimes and the other way better other times.

Seems like you are getting good results now, so I agree---leave it be and enjoy your solar :)

At this level I would stick with parallel.

X2 I wouldn't change unless you just want to experiment.

The series vs parallel scheme has been discussed on the Forum, previously. Sorry, I can't find a good thread about it.

Basically, with a smallish output of 200W, it will totally depend on if your controller is more efficient at the higher voltage and how much so. Based on your preliminary test output of 11.4 A, I wouldn't touch a thing. You are approaching maximum output and will have less shade issues with the parallel configuration.

I like higher voltage for less line loss, and working with much smaller wire.

In terms of run length, I have #10 wire from the panels to the controller, about 12 feet or so. From the controller to the batteries I have #2 wire about 3 feet or so.
As far as AMPS go I haven't had much chance to test yet. My highest output of AMPS so far is 11.4. I had to turn on everything on the trailer I could (including putting the fridge on electric, via my inverter) to get the solar to work that hard.

Hard to say..how long is your wire run from panels? You controller will show you how many amps are being delivered to the battery.