Oil sucks, wind blows.
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Nice looking setup. Looks very clean and professional.
Cheers.
TomW
"Nice looking setup. Looks very clean and professional."I agree but,Looks like battery set-up is right below this very clean looking system. I've read that the battery gases would be bad for the electronics and plan on keeping mine in a special area away from my electronics. (Wooden battery box for now,will be moved into chest freezer very soon as the nights are getting colder). Now I'm going to have to paint that old freezer so it looks a bit better! LOL!
If there is a weak cell in one of the panels, it will limit the current output of both panels if connected in series. Seeing as you are running a 12 volt system, it would be better to connect the panels in parallel to get the current you are looking to achieve.
It can't hurt to give it a shot!!
Blessing, Snow Crow
Kelly
The panels in parallel most be isolated from each other as well. Some of the power will go to the weaker panel, thus it never reaches the controller. This is a bigger problem with non-tracking panels without blocking diodes. When some panels become shaded, the current from non-shaded panel will go to those that are shaded!! This causes a much bigger drop in output than if all panels were isolated from one another.
I would put diodes on each panel, if you haven't done so already, and try it again in parallel.
Blessings, Snow Crow
knowing without a diode the battery would backfeed when the sun went down.
I keep seeing this repeated and I have to say I think it is a non issue. I have run mine both ways and I only isolate them now to keep possibly high turbine voltage away from them. When I was just solar I never noticed any losses out at night, despite reading this often repeated information.
I mean, PV arrays are strings of semiconductors and semiconductors all have junctions that are polarized. Kind of why protect a diode with a diode?
Just tossing that out for consideration.
Most should just follow manufacturers instructions. By now I have forgotten what Siemans paperwork said.
My understanding is that under some conditions enough back current can be driven though solar cells to cause heating problems and even damage as they are effectively fairly leaky diodes. I'm assuming that in this practice this can only happen for very different strings of cells (eg different nominal voltages or different types/manufacturers) or if some are shaded and some are in full sunlight.
I have put Schottky blocking diodes on the two panels in my tiny system (20W monoc 21Voc and 62W thin 15Voc) since they are so different. They also get shade at different times.
Rgds
Damon
My solar is all matched 75 watt Siemans panels [4] so that may be why it was not an issue. I am confident when it comes to testing different options and I would not advise anyone follow my lead unless they are clued in on electronics, etc. As I said in that reply most should just follow mfg. recommendations.