How-To: Anti-Spark XT-90S Loop Key

Agree it looks good. I like the copper to reach all the way in if possible and fill the hole more fully w/ solder.

Yea, that was the intent but then while soldering it got bumped up unfortunately. As long as it can pass the current, I’m happy!

Is there a performance or safety difference between using copper and a 12 awg wire?

Not really - for such a short run it should be fine. I would definitely go as thick as you can w/ whatever you use, and keep it as short as possible. That was the main reason i went with the solid copper - because it was direct point to point vs a loop of wire, and strong enough to then tug on w/ the paracord.

The only time i’ve heard of a problem is too thin of wire and a longer loop - more heat under load = bad.

Good to know. My loop key haven’t felt hot after riding so I think I should be good.

Sorry, newbie question. The anti-spark loop key is supposed to go on the + wire, between the battery and the VESC, right ? And it allows you to leave your battery in the board and acts like a on-off switch ?

Yes exactly! If you have a bms and charge port you should put it on the + wire in between the + of the charge port and the vesc. This way you can and should pull the key out when you are charging.

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Maybe I missed it in here, but wouldn’t it be more ideal to have the female side connected to the board and use the male portion as the “key”?

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Are the male ends Anti-Spark or will have to re-solder the female onto my battery and the male end onto my VESC ?

That’s a good way to do it as well.

Easier to secure the Male portion to an enclosure flush, and if the anti-spark portion of the key does get damaged (not fully seated you will melt the resistor) - a simple regular XT90 (spark!) works in a pinch and you can still ride.

Thanks for the panel mount models, came out great

One tip, after port inserted, heat up the mount for it shrink a bit to the connector, makes it impossible to push out the back even without a screw

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Question, would it be possible using a fuse holder, and a 80A fuse as an alternative to anti-spark loop?

You’d still get a big ass spark. The only two viable options are an anti-spark switch, anti-spark loop key or BMS with E-Switch.

This has been exhaustively covered many many time for a couple of years now.

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Good tip, I usually just use super glue, never have used screws. But that’s even better as you might be able to heat it for removal as well.

I embedded mine in the deck. I like to use the anti-spark male shape on the deck side as its cheaper to have multiple keys that way. Just in case I loose one. With this on the side of the deck I can access it from the top or bottom in an emergency.

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What if you burn out the resistor?

:confounded: :sob: Yeah since its epoxyed in it would suck to replace. How long do these things last? If it last 1000 insertions I would be happy.

Honestly don’t know, I’ve seen people burn them out quick, like weeks-months, though I’ve never burned one…

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Ive burned through like 4-5 lol

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You are very special :disappointed_relieved:

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