PSA: Wire Guages

Good thing I was working on my board and caught this. I installed some charge port with really narrow wires. I noticed my case heating up where the charge port wires were swapped in for the past few weeks since making this change.

Tonight I was working on a boost converter mod to charge on the go with some power tool batteries… Charges great! Charges fast! But… I was using the same wires/ports I installed earlier on the boost converter and noticed the wires getting fairly warm to the touch even at 42v2a. I had tried 42v5a, and they were really hot! Didn’t think shortening wires would help the bottlenecking of current at all so I decided to open up my enclosure to replace the charge port with some more legitimate 16 guage wires all the way to the 5.5/2.1mm barrel connector… And this is what I found.


Well, I’m in the middle of replacing all wires in the charge system loop to 16 guage or thicker. The resistance on the smaller wires, just a few inches worth, was 5-10x higher than even a daisy chain of connectors/adapters/16 guage wires.

The pros around here probably already know this stuff, but for the other noobs like me… If you notice something off… Investigate. And don’t think you can just put any wire on anywhere and be good. I thought it would be okay, and it was for the past couple months, but something was off… and okay turned out to be not safe.

1 Like

Did you change out the charge port too? Wondering what difference that would make. I am installing an mboards three pin charge port, and the wires looked a little thin to me, so I sent Mike a question. I’m building a 10s6p battery. I may change out the wires on the charge port to a heavier gauge. I may want to charge faster and therefore find a charger that will go over the 2A my current charger will do. Tempted to use my old evolve carbon AT gen 2 charger…