Hey everyone! I've got two sets of 190w solar panels wired in parallel, each set running through different charge controllers and connected to 100Ah AGM batteries. The panels are rated at 46.2v and 5.42a, but I'm finding that the voltage output from both charge controllers is capped at around 12.6v, even on a bright sunny day. I'm wondering if anyone has insights into why the voltage from my panels is so low when it comes to charging the batteries. Any suggestions would be really appreciated! Thanks!
2 Answers
First off, double-check that each string of panels is working properly. Sometimes, a failed bypass diode can mess with the output. Also, using two different charge controllers for the two arrays might cause issues since they can interfere with each other's tracking. It's usually best to have one charge controller per array. That setup gives you better voltage management.
Just a heads-up, you really shouldn’t parallel the inputs of different charge controllers. It’s safer to split your arrays and run separate charge controllers for each, then connect their outputs to the battery bank. Make sure the connections are done correctly to avoid conflicts.
Thanks for the advice! Just to clarify, the two panels are indeed wired in parallel for a combined voltage of about 46v and a bit over 10a going into the charge controller, right? Measuring the input shows around 12.7v coming in, but only 12.6v comes out, and my batteries aren’t charging above 12.8v. Any thoughts on that?
Are you talking about the bypass diode specifically? That’s something I might need to check!