Anti-spark plug sparking?

Hi! Very new here :slight_smile: glad to be part of this colective I recently built my electric longboard, this is unfortunate because i feel I dont need a girlfriend now, as I spend tones of time in it…

As a first question in the forum, I have a problem with the antispark plug wich I could not find the answer in the other posts: it sparks anyway! is this normal?

some info prio to the spark:

this is a 12S 1VESC

  • motor longboard , postive cable going to VESC has the antispark female in the middle, and close the circuit a male with a fuse.
  • when i plug it half way ,precharge circuit with the resistor, the VESC blinks (I understand here capacitors are charged and i can go all way in)
  • when i go all way in after some second(s) a spark sounds in the XT90 antispark, then VESC turns ON and works fine --for the moment…
  • after that, nothing broke, resistor in place, no magic fumes and stuff like that… in any case im afraid to plug all the times as the spark actually happens despite the setup!

thinking now on using an extra antispark I have from DIYelectricskateboard

Best regards!

i ve use 90s countless time but never had that issue before. may be u need new 90s. btw spark won’t kill anything. it just eat away ur plug everytime it sparks.

Please post a photo of it

Hey Thanks for the answers!,

Well before not using an antyspark plug it actually burned a capacitor and lifted a track out of the VESC… wich I had to resolder :frowning:

If this helps, I only hear the spark with 12S, when i am plugging 9S, 6S or 3S there is no spark.

I will replace the antispark and lets see… THX!

1 Like

youll need to replace the plug with the green. it has a resistor in it and that makes the circuit first for a split second reducing the current and that stops the spark. ive gotten sparks out of my xt90s after they finally burn out. its not the worst thing and will just damage your connectors and increase the resistance there, and make a scary spark. weird how you say it wont happen with the lower voltage @Fafu interesting you burned a capacitor out without the antispark. was it one of the big ones going to the battery or on the board. I imagine with a huge current spike charging the capacitor it could be more rough on them but never heard of it being the case


Regarding the first comment on the green plug, that the one I actually use! it works making vesc blink when is pre-inserted, but sparks when I finish to put it in… so lets say it does not fully work as expected, like capacitors have time to discharge before i fully plug and then Sparks? Will replace the antispark tomorrow and let you know!

Regarding the capacitor, was the c51 form positive to floor, the track taking that current shorted,Capture

the track to that capacitor shorted, (that track has 2 or 3 paralel tracks underneath but rewelded it anyway because 12S might take too much current and that extra track might be needed… Capture2

What I think regarding the capacitor and the track, I never used antispark with 3S at the begining and something broke. plugging one day the 3S this happened. I cant tell 100% if it is related But now with new capacitor, track in place and antispark (sparking :S) it works fine


Mate, get a Vedder antispark! They are not expensive and very nice

Guys!! Just replaced the antispark… IT WORKS! well that is strange, maybe it was dirt and current didnt flow fully when half plugged: vesc didnt turn On 100%, only blinking, but now it does!

I did a super small fuse with 2*20A car fuse :slight_smile:

can you tell me what you did because I’m confused. Are those two 20amp car fuses you used to make antispark loop key? 40a max? that’s not much and would likely be high resistance. and you didn’t replace the green side just this side? I’m confused as to what your problem was originally now since you didn’t replace the green side with the resistor connection

Bridge that connection with large gauge wire or copper. I don’t know where that idea came from but don’t do it. Like hummie said, more resistance and wait till you blow that going uphill or accelerating fast = streetface. A fuse like that isn’t a good idea.

Hi! Sorry i understand it is confusing, i replaced the green part, and also the male as both looked very dirty/burned

So the male is the fuse I did it new, using 2x20A car fuses, removing enclosue and welding it.

Regarding the fuse value, well, i will try 40 and limit with vesc slightly below that value. When i get more experienced i could increase, what do you think? FYI i had the chance to try it only a couple of times before something broke… But now things look promising!

I think you should not do a fuse like that. I think you should bridge the gap with wire, not a fuse whatsoever.

I see… so maybe the question is, why do we need a fuse?

You don’t.

yeah fuse is over-protective. why people even use it? maybe for fet switch ( even this is questionable)

anyways, it may have been the solder part of old 90s is nearly touching, and on 12s was arcing through the air gap.

Understood!! Thanks to all

How do you protect your ESC if there is short-circuit ?

At the end i decided to keep the 40A fuse, monitor current in a normal ride, see how far I am, cover the fuse with isolating tape, and vesc limit battery current to 35A. In any case 12s and 35A is a >1.5kW wich i doubt i will use… I read a bit, if vesc shorts, i dont to set the longboard on fire so the fuse i think is important!


Is that how a fuse is supposed to work? ive never used one so don’t know and never think about them but is it simply putting a super thin and high resistant part in your circuit that will melt at a certain amperage because in doing that you will be making the system more inefficient and more likely to have voltage sag. Id think youd want a fuse that would still do a lot more current to keep the system efficient and if you did have a short it would be a lot more amperage than 40.

The fuse only holds a certain amount of time the rated max load. But if we use a 40A fuse and will get over that amount on every ride for a second. Will the fuse last Long?