A few observations on my solar arrays

Product Discussion Solar Panel
1

I have one large 10x100 watt panels, and two lesser ones in parallel producing about +630 watts total.
My theoretical 1000 watt array on DC1 only gets to a max 964 watts or less.
.
The AC500 looks like it tries to keep DC1 and DC2 fairly equal, around 632 watts each, pulling down DC1’s wattage to equal DC2. I can only assume that has something to do with battery management, letting some +330 watts on DC1 go to waste. See pic.
.
When I unplugged DC2, DC1 shot up to the mid-900 watt range.
.
So NOW I find out that you need to plan your arrays so that DC1 and DC2 be close to equal wattage, or the AC500 will do it for you. Kind of sucks since I had just added two more 100 watt panels to DC1 to get to 1000 watts. I’ll have to find matching panels for DC2 to increase the output, to match DC1’s extra wattage. That won’t be easy since some came from Craigslist and the others are no longer available.
.

On another observation, just being able to tilt my 10 panel array by 23 degrees (according to my tilt-degree iphone app), toward the sun at around 3:30 pm produces 200 extra watts. Panels are more directional than I thought. So should you need max output during an extended blackout, there you go. Just a 3-1/2 hour difference from high-noon was 200 watts.
.
Just one splat of bird doo-doo also reduced output by about 50 watts. He hit dead center on a square. It washed off easily enough, but still… :face_with_raised_eyebrow:

IMG_0231
IMG_02312048×807 60.4 KB

2

Hast die Panele in Reihe geschaltet oder parallel?
Wieviel Volt sind an den Eingängen?

3

1st Q:
DC1 is an array of ten 100 watt panels in series. By itself, output is in the 960 watt range.
.
DC2 has two arrays, wired in parallel so they don’t exceed the 150 watt input. Each of these two arrays consists of series wired panels. Output of each is in the mid 600 watt range.
.
The more I think about it, the likely cause is that the batteries were at around 95% SOC. I’ll look at it again tomorrow with the batteries at a lower SOC and see if that’s it.
.

2nd Q: See pic.

4

Followup:
It looks like it was the Battery Management after all. I watched it all day today while recharging the batteries from last night where they were down to 28%. The panels were producing almost 2 Kilowatts, up until around the mid 90s% SOC, then it started tapering off the input power to where both DC1 and DC2 equaled out around 630 watts each, same as yesterday.

5

Ich habe SOC bei 50%…das funktioniert sehr gut.

6

Heh, translating German into English was messing up my browser. When I went to Amazon everything was suddenly in German because it was Amazon’s Germany site.