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Blew a charge controller by not reading the fine print on panel voltage
Put up two 400W panels in series thinking it was fine for my 12V system, but the open circuit voltage was way over the controller's max. Cost me $120 to replace it. Anybody else smoked gear by assuming series would just work?
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the_wendy2mo ago
You mean you never checked the VOC on the panel sticker before? Man I used to think it was just fine too, that series wiring was just plug and play. But then I blew a 60A controller on a cold morning with two 300W panels in series, the voltage shot up to like 92V and it fried. @jessica707 nailed it, the rated voltage is way lower than what the panel actually puts out when it's cold. That $120 mistake really changed how I look at those specs now, I guess you live and learn with solar.
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jessica7072mo ago
Yeah, that's a rough lesson. The issue is a lot of people think series just doubles the voltage, but they don't check the VOC spec which is always higher than the rated voltage. Always gotta look at the controller's max input voltage before wiring anything.
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juliarodriguez2mo ago
That 92V cold morning spike got me too, actually. I had two 330W panels in series and woke up to a fried 40A controller one frosty November morning. The VOC on my panels said 48V but I figured "eh close enough," didn't realize how much colder temps push it up. That $120 replacement fee stung but honestly taught me more than any forum post ever could.
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