ABS_OVERCURRENT help!

So I’ve been having an issue where when throttling hard my motors (maybe both maybe just oneI can’t tell) will engage the brakes for a split second and almost throw me off. When using metr there is no fault detected but using xmatic I get an ABS_OVERCURRENT alert. I recorded with metr and have highlighted what I believe to be the moment during which it happened once:

Here’s you can see the whole recording:

As you can see the VESC temps and motor temps are running pretty high but are these current values really that high? I’m running dual VESC TB 4.12 with brand new Maytech 6374 190KV motors. There was an issue a few days ago where I wiped out and thought I broke a magnet in one of my motors because there was something scraping and jamming up the motor when I’d try to spin it, but I opened it up, found nothing, put it back together and it’s been fine since. the only thing I have noticed on that motor though is that it doesn’t spin/coast QUITE as long as the other one when I spin up the motors and then let off the throttle (stops spinning maybe 2- or 3 rotations before the other motor), but I really didn’t think that was a big deal or a problem. I don’t know if it could be related to the ABS_OVERCURRENT and the braking issue, but I’m just laying out all the variables here.

I’m running in FOC mode with the following limits:

I also have my throttle curve set in ackmaniac to Throttle Exp value -10% & Throttle Expo Brake value to -10%.

I’ve tried switching to BLDC in metr but it always fails to write for some reason (I’m very new to this app and may be doing it wrong), so I will prolly hook up manually to my computer and switch to BLDC in Ackmaniac to see if the problem persists. I haven’t gotten thrown completely off my board or injured myself luckily like some other people who have had this issue because I’ve adopted a pretty solid downhill stance, but it’s shaken me pretty bad and gotten me pretty close a couple times on the road. It’s scary and shaking my confidence to push this board. I’m bummed because I like hitting uphill hard. How does this all look to you guys? How crazy do my current limits look and how can I try to manage this issue? Any help would be greatly appreciated thanks!

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Abs over current faults are typically due to a bad connection somewhere in the line. Check all your solder joints etc. Often it’s also broken capacitor legs (that’s what mine was).

It’s not engaging brakes just essentially reseting itself when this happens but it sure feels like a sudden bloop of brakes, shits scary.

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yeah check for lose phase/motor wires or connectors first

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@stratoglide what’s a broken cap leg look like? These seem in order no?

!

hope that second one’s not too dark

They look fine but so did mine it wasn’t until I wiggled it that I could see where it had cracked. But really it could be a broken connection anywhere.

oof alright this’ll take a while

Would using a multimeter and checking continuity work for this? They’re so tiny it’s hard for me to see

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Check motor bullet connectors, minimum play could lead to an ABS over current… You can set the cut off to 10A so you do not sudden stop after it happens…

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I did pinch one of my phase wires under my tunnel riser and broke the insulation - I wrapped it in electrical tape because it seemed like it was only the insulation. It’s possible I broke a few strands of the wire tho, would this lead to such a problem?

huh? you couldn’t have possibly broken a few stands of wire by pinching it, it could be the cables are under stress in your tunnel riser.

I broke the insulation exposing the wire underneath, I think it’s very possible I tore some strands. Will take some photos when I get home from work

UPDATE:

After checking bullet connections, phase wires, continuity between solder joints on VESC and caps, I’ve come across a few issues and most notably, have found what I think is causing the ABS error. @Santino I believe you were spot on; opened up all the shrink on my bullets and the on the last one the bullet just fell right off…

I remember when soldering this bullet it was a shitty job but being like “ahhhh IT’LL BE FINE WHATEVER” and just rolling with it…SMH to myself, ya live and learn I guess…

A couple other issues I found were exposed wire. @AlanZhou this is the spot that got pinched which I covered in shrink:


first before removing shrink

then under shrink with insulation peeled back.

Here’s another issue I discovered. Some glue I used fused together the insulation between one of the phase leads and the sensor wire and somehow the wire going into the bullet got exposed:


gunky bits of foam and krazy glue that got in between

wire connecting to bullet exposed.

So obviously I’m going to resolder that bullet, I’m just wondering how I should manage those 2 issues with wires exposed? Just shrink over them? Thanks for the input and help so far guys

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I would use Liquid Tape to isolate it, and shrink tape for sure. And probably with more time, I would replace the wires for new ones…Happy for being helpful!

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Woah that looks like the silicone around the wire is cracking

This happened to me last night. Rode around for 5mins figuring out what was wrong :joy:

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