Hello, newbie member here. I have my small 12 volt system up and running on two 100ah amperetime's. I have 4 Rich Solar 200 watt 12 volt 9BB Mono panels but only 400watts out of the 800watts connected in series currently. Can i connected all 4 panels in parallel. I have been reading everything on here and the tube and lot of the resources here but its not sinking in completely. I am using 10awg pv wire and 6awg on my batteries. This is a back up power for my Reef Aquarium and runs it all great but could use more power to charge faster. I have a couple of portable power stations i was using and still use for extra backup. I live in eastern Michigan.
I have ran 3 in series and 4 in series/parallel just to try it on a 12 volt system. Sunny day and with a load from my well pump. It worked fine, but I didn't get over 36 amps going to the batteries and about 570 watts to the controller either way. So you can run series/parallel and overpanel in crappy weather, but sunny days it doesn't really matter. I hooked up 1200 watts in series/parallel once to tru it, but it's way overkill for a 12 volt system. The Rich solar 40 amp controllers show a fault at about 92 volts so 3 in a series is best. On a cloudy day you can get away with 4 in a series. Hopefully this helps!