question

dstreight avatar image
dstreight asked

100/50 MPPT controller leaving 100+ watts on the table...

System: 4-Rich Solar Mega 200w panels on the roof of our tiny RV trailer; all 4 purchased from Rich Solar at the same time and deployed at the same time. We have two (2) panels stacked, on each end of the roof using drawer slides to extend each upper PV panel when stationary/parked.

Each pair, upper and lower, drawer slides mounted respectively, are connected in series and each string are on the same network for charging.

String 1: Victron 150/70. Typically seeing 350-375w output from the pair of upper mounted PVs

String 2: Victron 100/50. Typically seeing 225-250w output from the pair of lower mounted PVs when the upper panels are extended (exposes these two lower panels).

Separate runs of 10AWG from PVs to MPPT controllers.

Question: With identical PVs, wire runs, etc., why is the 100/50 effectively "clipping" 100+ watts compared to the 150/70 controller?

MPPT Controllers
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2 Answers
snoobler avatar image
snoobler answered ·

Assuming there isn't even the slightest amount of shade on the array in question (if there's even the smallest amount of shade, that's your issue), have you swapped the arrays/controllers and confirmed the problem is tied to the 100/50 and not the "lower" array?




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dstreight avatar image
dstreight answered ·

img-1405.pngSheesh, I forgot I asked this question last month but will delete the duplicate question.

Zero shade on any of the 4 panels. I have them named "Top" and "Bottom" as I have them mounted on drawer slides...

No, I have not yet tried swapping the controllers but will try that soon to see if its panel or controller related. Just curious if there is a significant efficiency difference between the two controllers.





img-1405.png (716.9 KiB)
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