I’ll not sure exactly, i tried reading up on it a couple times but it mostly goes over my head. Vedders official documentation on the vesc you says you should try doubling or halving observer gain if your motor acts erratically. This fixed my over current faults on fw 3.xx.
Did this fix your issue?
Hey mate, im having the exact same issue. Thinking of going back to BLDC. I’m using an Enertion Focbox for my ESC in FOC mode, and at least once or twice a day i get ABS_OVER_CURRENT. It’s pretty scary when you’re doing around 35-40kph and go for the brakes and they just arent there until your board starts working again.
What setup are you running with FOC?
Hey,
Did yo uever fix this ABS thing? Im about to swop out a 4.12 Vesc for a Focbox and I was going to change to FOC mode after the swop.
hey mate, i actually dont seem to have the issue anymore after my rebuild. but im running 2 focboxes (in FOC) mode now. so i may still be getting it but not noticing as i have some form of redundancy now for the brakes.
i re-did the measurements part of the BLDC tool setup and i dont seem to have problems after making both focboxes identical with their settings.
both are running individually (no CAN bus) just a Y splitter and ive cut the ground going from one of the focboxes to my receiver. its working really well
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Hey, well, I swopped out my Maytech to the Focbox and have no issues. Im back on my 100mm MBS with a 42T pulley and no over heating of vesc like I had before. FOC mode is great too so Focbox seems pretty solid!! Sweet.
I have been running the same SK8 VESC with different motors and with a mix of FOC and PWM/BLDC control modes. It seems that I’m getting substantially better efficiency with PWM/BLDC mode than with FOC, I’m afraid. Like 15-20% difference in PWM mode’s favour. I can even feel the motors getting more warm with FOC, so it’s no mystery where the power goes.
FOC mode sounds better / more quiet, though.
So what is your preference? Foc or bldc? I’ve also noticed that friend’s that run Foc seems to have higher temperature on both vesc and motors compared to me who runs bldc.
Bjork, I’m still very new in the EV game, so still experimenting. But I’m not happy to loose 20% range for a more silent system. Or have the motor running at twice the temperature. My build is over here: https://endless-sphere.com/forums/viewtopic.php?f=3&t=97578
foc
bldc
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I have just concluded a simple 3km test with the exact same set-up and near identical condition. In FOC, the recharge was 1020mAh, and in normal PWM (“BLDC”) mode, the recharge was 860mAh. The motor also seemed noticably cooler in “BLDC” mode.
So, in my case, “BLDC” mode outperforms FOC mode in efficiency 
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We both know which one we’re taking for a wild ride tonight!
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haha yeah excatly !
I got this picture in mind :
foc
https://www.fixpowersports.com/wp-content/uploads/2016/08/img-17.jpg
bldc
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Weird because foc is supposed to be a bit more efficient according to vedder.
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Thats a good looking BLDC bike, check out my profile pic 
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Wait, wouldn’t that imply that FOC is more effective at converting mechanical to electrical and vice versa?
Can u adjust switching frequency in bldc?
Yes, I thought so too, but there may be an issue with FOC if running at near maximum rpm.
I don’t think that is the case here, though, as I’ve tried with 4 different motors and gearings, and I get the same suspicious drop in efficiency everytime I use FOC mode.
No, that would not be an implication of the FOC being more effective. Not in my book, at least.
Haven’t ridden BLDC in a few months now. FOC is just much smoother and leave your build with more of a polished feeling.
Have not had any issues running VescX/Focbox.
Now bldc and FOC feel pretty identicle at any rolling speed there is just a sound difference and a much smoother start from dead which makes a huge huge difference riding pnumatics in the grass or gravel.
Have you tried to kick push a pnumatics wheel board in the grass to get it going in bldc? It’s not easy and I have thrown my back out doing that haha.
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