My 24V solar panel put out 30V at noon today and I nearly fried my charge controller

Found out from a YouTube comment on Will Prowse's channel that some panels can spike way above their rating on cold sunny days, and now I'm wondering how many other newbies have toasted their gear learning that the hard way?

3 comments

3 Comments

jamieb801mo ago

Wait isn't 30V pretty normal for a 24V panel though?

drew_jones311mo ago

Yeah @jamieb80 is right but man on a clear cold day my 24v panel hit 32v and that voltage regulator got real spicy real fast.

blair_nguyen1mo ago

oh yeah that cold sunny day voltage spike is no joke lol. i actually just went through this exact thing last month with my 12v setup. what worked for me was throwing a simple overvoltage cutoff relay in between the panel and the controller. cost me like 15 bucks on amazon and it saved my gear when the panel jumped to 22v on a freezing morning. not the most elegant solution but it beats replacing a fried controller. also started checking the voltage with a cheap multimeter before connecting anything just to be safe, takes two seconds and feels way less risky.