I want to explain this is not my proudest moment, but there are a few things to learn from what I did, and also some interesting observations about barrel jacks like this.
So things I learned:
Do not measure voltage from a barrel port with multi meter probes regardless of how careful you think you can be about not creating a short.
This is not an anti-spark type connector. I don’t think I actually made physical contact between the two conductors, I think a spark crossed the air gap. This is less of a concern when using the actual barrel jack as it uses a plastic insulator to prevent this. However, on to lesson number 3:
If a spark does occur then the resulting ionized air (plasma) will continue to conduct resulting in an arc-flash condition that continues until the internal post of the connector is fully consumed!!!
Most Interesting to me: The resulting chamber that remains and the fact that there is still voltage on the barrel and the little nub that is left… It left a got damn floating plasma ball inside the connector until I blew it out! It wasn’t just fire because… I was watching waiting for it to burn itself out… but it was self perpetuating. Cool, my board is now an ion generator.
So what now? Different more safe connector is what. What is the recommended charge connector style? GX16-3?
Honestly, I don’t think barrel connectors are safe for esk8 at all.
EDIT: a 5a fuse on the charging port wouldn’t be a bad idea either.
In all fairness to barrel jacks, ive never had one fry on me for any reason. The only time i ever really hear of them frying is when people use a multi meter on the charge port, or just lack the knowledge to properly build a battery. In your case it was the first.
You should have taken your own advice… Dont blame a part that works fine when you caused it to fail.
But a fuse is a great idea. On the negative side. Like @b264 preaches. Over and over again.
And youve been here long enough to have seen it posted. I rhink you only have yourself to blame bruv. But i wish you safe journey building/repairing.
Edit: So maybe you havent been long enough lol. Just checked your profile. My bad bruv.
Secondy, I just went ahead and searched every datasheet I could find on these connectors and they are rated for 20 to 24 volts. So they are being used out of specification, and these are the failure modes you can expect.
That’s all I was pointing out. Yeah it probably wouldn’t have exploded had I not had a piece of conductive metal near the port. I guess my concern is what if something metal whacked the connector while I was riding.
I mean, for example you could use an XT60 where you should be using an XT90 but you’ll only experience the learning lesson after something goes wrong. The connector on it’s own isn’t the problem it’s the application and HOW it fails.
EDIT: I’d like to say that the connector is fine while CONNECTED. The insulation resistance is rated for 500 volts. The problem is the higher voltage increases the potential for the spark. And yes of course, with a good fuse in there the fuse should blow before any appreciable damage is done to the connector.
The best connector in my opinion for size and amperage is a gx 16-4, there’s 4 pins and each pin set can handle 5a so if you use 2 pins for negative and two for positive you can do effectively do 10A rated up to 1500v AC
^though I don’t know how much I trust the 1500v AC rating