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Anti spark connector burnt my vesc?

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v71n24908c27h8bn9
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Anti spark connector burnt my vesc?

Is it a big no-no to give small amount of power with anti-spark resistor connected on the battery->vesc connection?

 

 

 

 

Connected everything as in picture 3, with only one of the three xt90's connected. And also with an anti-spark adapter (which is only a 6.43 ohm resistor on the positive lead).

Gave a small amount of throttle (~10-15 amps), only got noise/clicking sounds from the motor. Like it's some kind of hall sensor error. Never spun.

Got "low input voltage" error in the vesc app. (Which is weird because the 72v battery pack was at about 85-90% full charge) and minimum voltage in vesc app at waay under that.

 

I thought that maybe the resistor is fooling the vesc somehow so I connected another xt90. Now it looks like the 4th picture.

Gave a small amount of throttle again (~10-15 amps) and instantly got a huge arc and pcb smoke.

 

Sorry for wall of text, but do anyone have experience with this? I should probably not have started the vesc with the resistor-adapter connected but should this really happen?

Thanks

electricfox
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At that low current this should not happen and it has nothing to do with using anti spark connectors. It looks as if there was corrosion? The light blue small parts here and there makes me think of that. 

v71n24908c27h8bn9
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I've been riding in some wooden areas and trails and must have gotten something inside the vesc to short it?

Doesn't the pcb have conformal coating? Maybe im naive indecision

electricfox
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I´ve seen lots of burned ones on efoil forum because they got water inside the Vesc. Vesc has no coating on PCB. 

vadicus
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Unlikely that the antispark caused this but I realized most resistors used in those type of connectors like XT90 etc. have too low of resistance to be effective in suppressing the spark and the stress on the caps.

It seems like the built in low resistance was meant to be used with way lower voltage, nowhere near 72v. I would likely need a resistor in hundreds of ohms range for the anti spark to be effective for your setup. I've used BMS to slowly connect the battery at low amps like 5A which worked great as anti spark. In the long term, of course the caps will serve longer if a pre-charge circuit is used.   

Spaceman
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Cause of damage may have been due to ingress intrusion?  Visible around SMD caps before shunts.  VESC's housings are not IP rating !  

Conformal coating may help preventing moisture to PCB's. A vacuum sealed housing would be the ideal solution splashing around water.