I recently bought three used solar panels and checked each one with a multimeter. They all show the correct voltage and amps, so I expected they would all work. However, while one panel works perfectly, the other two don't seem to charge my portable battery at all, even though I'm using the same cables for each panel and they're all the same model. Does anyone know what might be going wrong?
2 Answers
If you've tested the voltage and amps directly at the connections and everything seems fine, it’s worth checking the specifications of your portable battery. Some models, like certain Anker batteries, need a higher voltage to charge properly. What model are you using? That might explain the charging issues with the other panels!
It sounds like you're saying only one panel works individually? If that's the case, it could be that the two non-working panels have issues despite the multimeter readings. Sometimes, problems aren't immediately visible even if the voltage looks good. Have you tried any troubleshooting on the panels themselves?