I've got a head-scratcher with my solar panel setup. I've connected two identical 175W 48V solar panels in parallel to a Victron 100V 20A charge controller, but they're only producing the wattage of one panel. Individually, each panel works perfectly, so I'm puzzled why they aren't working together. I've used heavy-duty wires that are thicker than those coming from the panels, so I don't think it's a wiring issue. Also, since both panels are 48V and I'm charging a 12V battery, I know they're not reaching full power, but I expected at least some increase in wattage. I'm working with leftover parts, which limits my options. Any ideas on what's going wrong?
3 Answers
It's strange because your 20A controller can handle around 280W, so the second panel not contributing makes it puzzling. My first guess is there might be a bad connection somewhere, especially if you're using Y adapters. Double-check those!
Have you tried covering one of the panels to see if the output changes? If you cover one and the output drops, that could indicate a connection issue, maybe with the Y connectors. Just a thought!
I’m curious—why did you choose parallel instead of series? Series is generally more efficient unless you're dealing with voltage issues. Just wondering if that's something you've looked into.
Yeah, totally makes sense! Parallel is useful for shading issues, but efficiency can take a hit.
The voltage was too high for my controller in a series setup, and I thought parallel would help if one panel gets shaded. But it’s good to know there are pros and cons!