Hey everyone! I have a not-so-great question I need help with. ? I've got an Oupes Mega 1 portable power station that accepts solar input rated between 12-78V DC and I want to hook it up to some old solar panels I have lying around. These panels have a VOC of 37.6 each and, when I connect them in series-parallel, I get a total VOC of 75.2. I'm concerned if this is too much for my MPPT that caps at 75V. Plus, would using a longer cable (10-15ft, 10AWG) make a difference in lowering the voltage? I'll only be using this setup at Burning Man where I don't anticipate low temperatures. Any advice would be super helpful!
3 Answers
It's definitely a risky setup. Your panels may exceed the 75V limit, especially in good conditions. As for the 10-15ft cable idea, it won’t actually lower the VOC since that’s the voltage when no current is flowing, but it might impact voltage drop under load. I’d avoid connecting them unless you're ready for potential issues.
I wouldn’t advise it, but if you’re intent on trying, consider disconnecting one of the series strings at night to help manage the voltage. Just make sure to connect them when the panels are warm and not early in the morning when they can surge due to lower temperatures.
Honestly, I wouldn't recommend it. Even though you're looking at 75.2 VOC nominally, these panels can actually produce even more voltage under optimal conditions. Exceeding the voltage specified by your MPPT could lead to serious issues, including damaging the device. I'd play it safe and look for panels that more comfortably fit your MPPT limits.
Got it, thanks for the heads up!