Need Help with key loop

Hey everybody,

So I’m currently working on my first build and it’s coming along pretty well, until I tried building my anti spark key loop. I have two lipos connected in series with a series adapter going into another series switch which connects the anti spark key and the vesc. When I tried plugging in the key switch for the first time, there was a huge spark that basically fried one of my series adapters. Thankfully the batteries and vesc still work. So is there something I did wrong? And can someone tell me some specifics about how to build an anti-spark key loop? Should I just give up and buy a vedder switch instead?

This was the first page I went to when researching. Everyone says that it’s just a simple series adapter with a key switch that closes the circuit. I’m pretty sure that’s what I did, unless I missed something?

Show us your connections irl or on diagram. I had a situation similar to that of your’s but that’s when I used 13s. Not sure how much difference it would make depending on your setup but voltage could definitely be a factor. Could you have gotten the polarity wrong? :thinking:

Just to make it clear you are NOT connecting + and -. You are taking for example the red/+ line between the battery and the vesc and breaking that with an XT90 Antispark connector.

That is what I did ;(

I’m running on two 4S in series so basically in 8S, so not as much voltage as you’re running lol. I’ll have pictures up in a moment so I could show you what I did.

Edit: Not the best Diagram in the world but I hope that’s understandable

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It looks from the diagram that you connected the battery negative to the Vesc positive.

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How huge? Show us a photo of the burn mark. Some sparking may be normal under some circumstances, but unless I see the crater in the metal I can’t say.

A photo of the wiring and adaptors and loop key would help as well

Are you using a XT90 and not a XT90s? The first one is a normal plug, the second one has the inbuild resistor, which surpresses the spark.

Oh yeah I made this in a hurry, so it wasn’t really that good. But I did make sure that the positives were only connected with the positives, same with the negative wires. Sorry for the confusion.

I did not know there were different variations to prevent a spark. This is probably what I need. Thank you!

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It was pretty huge. Almost like a small ball of light lol. I’m not at home right now so I can’t show you some pictures, but the burn marks weren’t that bad. I just saw some black marks inside of the connectors. But it was enough to short out the series connector I made.

If you dont have a specific anti-spark connector like this ( then it will spark alittle every time you connect it.