Yeah I have done the same many times with focbox etc. Also pulled many guys with empty battery’s etc. Never had any issue
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Is that using 4.xx hw?
I’ve noticed this through my own vescs and through what others have posted online. Either the hardware is IMPOSSIBLE to kill, or it’ll blow over like a leaf in the wind.
E.g. I abused the hell out of my 4.xx with 80 motor amps and 40 batt amps and while they were at 80c after a mile or two, I could keep riding them as long as I wanted, just at the limited speed (which wasn’t even that slow). Or you can get a set that pops the drv when the first hard breaking comes up.
I’m hoping that since these are derived from a Focbox, that they’ll have the same -unreasonable- amount of durability 
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I can pretty much guarantee you that regen from braking didn’t spike your battery voltage 10 volts (from 47 to 57). You can see before the spike occurs battery amps are only at -9 amps which is almost a regular charging current.
There’s a few likely possibilities:
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Antispark, wiring or BMS switch cut, are you wired direct to battery with something like loopkey? or you have something intermediate that could cut connection to the battery?
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Bad voltage reading on the ADC, there’s various ways the battery voltage measurement on the ESC could get polluted. Something like a cold solder joint of voltage divider resistors, or bad routing that allows induced voltages on the high-impedance signal to mis-read pack voltage. If its the routing one we will see more reports from more people, if its a bad solder joint it could be unique to you. The voltage reading looks relatively normal so I don’t think it is this.
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Bad calibration and or motor tracking. Probably least likely in my opinion, possible your motors lost tracking under high current command and spiked current which could cause local spike in voltage.
Edit it’s not this, the logged fault shows 57 V I missed that:
- Incorrect setting on unit, it looks like the unit was reading 48V when the fault triggered, is your max voltage limit incorrectly set to 48V? It should be left at 57V.
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6.6 HW
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Another ride down… no faults here yet.
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Yknow Maytech was making those Rheostatic brake things to fix this problem, it’s too bad that they’re so big though, I can’t even fit them in my case lol
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I should have mentioned this - i have anti-spark inline bms is charge only.
i went back and looked at the faults and this occured (2) other times and were at similar slopes but right at the beginning of my descent with foliage on the road, i assumed my wheel caught on them and just hopped back on and continued on my way.
I’m reworking my enclosure just to fit one of these.
They’re actually not that big really. It easily fits in the space of 2x 18650 cells.
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My enclosure is pretty tight to be fair since they’re split. And the one they sent me is only for 10s, I’ve had it for a while, my board is 12s though.
Idk why they would need a 10s one though except to counteract normal spikes, the 12s ones are way more dangerous to the VESC obviously
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That a latching switch plugged into it? I don’t have one of these flipskys. I’d say the most probable cause would be some type of momentary disconnect of the switch if the BMS is bypassed. You are 100% sure the BMS is fully bypassed right? Because that would be the most obvious in my eyes.
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Jeff - thank you for the quick and detailed responses you are too kind.
the switch is momentary for on/off function - maybe i should swap in a loop key and try to recreate the scenario
i’m 99.9% confident as i wired it myself and it is not inline. the 0.1% doubt is due to your inquiry, i will validate and report back if this is incorrect.
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confirmed BMS is not part of the power delivery circuit and was not even connected during testing. Thanks again for the suggestion.
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yeah, maybe remove the switch from the equation.
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will do, will have some free cycles later in the week and will report back. thanks again
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Nice! Will you do the same route again without the switch?
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Lee this is science being conducted on the internet; of course not! 
yep route is not far from my home so plan is to make adjustments, test, and report back by EOW.
edit - dont know if i can exactly recreate the battery level though, but will do my best to keep as much static as possible.
arrg i just remembered, i finally got wheel weights and my pneumatics balanced last night. oh well consistency is key, will put the urethane back on and finish this task first.
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You are a good man 
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Rides from today.
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