broken bms/vesc?

Took my board for a ride, probably its 5th ride, and i got two over voltage faults on the stormcore app and now my boards all messed up. It shut off and only turned back on once i took the enclosure off. When i put the enclosure back on and rode it for 10 feet it did the same thing and only would turn back on when i took the enclosure off.The xt60 to xt90 adapter was a tiny bit loose and when i would wiggle it the power led would go from green to red and the board wouldn’t work so i reseated that and it quit doing that. Put her back together and went on a ride and everytime i would brake it would over voltage again. On the stormcore app the battery percentage would go over 100% from 85%ish and while under power would drop to 1-10% for split seconds. I downloaded vesc tool on my phone to check more stuff while riding and the bms had no readings at all. Is my bms fucked? battery max is 70amps so i set it to 32.5 and regen to -17.5. motors were a couple amps below max too. it rode fine yesterday but today just decided to shit out. its a 12s4p 21700 Panasonic from boundmotor. ive had so many issues with the board already its crazy. Had the bullet connectors come off on the first ride (i was too lazy to securely them properly) and it shorted or something on the vesc and one side wouldn’t work until maybe 30 minutes later and then was fine after that.

Any ideas? Can give any more info yall need.

i doubt u have a vesc bms, so the bms terminal in vesctool got nothing to read

u should be glad the esc still works after that incident, a lot of others will just die on the spot

have u check the soldering on the connector?

Can never give too much info.

which connector?


oh boy

check your Max and min voltage settings in vesc and all your connections that they aren’t loose

theyre all fine now. the only thing loose was the xt90 and that was only slightly loose and would fuck up and turn off the vesc after i hit big bumps or would manually apply pressure to it but unplugging it and plugging it back in fixed that issue. now i just get over voltage faults and the battery going from its correct percentage to very very low percentages and back within seconds and upon braking the battery going over 100% whereas with the same vesc settings it wasn’t before. could the over vaultages fucked my battery?

i redid the motor detection and it gave me this…

which seems veryyyy off. I have Tb DD’s 75kv.

the top value is the default for medium outrunners

forget broken bms you ever broke your own motors because the mounting screws were too long

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no matter what the one motor always comes back with 30amps): while the other keeps what i have it set to

Vesc tool is derpy. Sometimes it says that but the actual values are loaded. Check the motor config → current for both sides. It should be correct. If not, reinstall your firmware

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ok will do. do you know what would cos the over voltage issue tho? even with it set to -15 amp and having the battery at 85% with no load if i hit the brake it shoots up past 100%… that can’t be right… right? i cant recall it regen-ing that much before

This is most likely the reason why it dips down to 1-10% under load. 70A is an overrating for such a pack. Sure you can draw 70A or more but the voltage would sag so low just like what you experienced and it would only get worse over time.

dat difference and the overall 2nd motor reading… time to buy new motor(s)

Pretty much what happened when I abused the liitokala battery pack on my very first board. By abuse I mean drawing too high amps from such a small pack. It resulted in drastic capacity reduction which leads to severe voltage sag under load and overvoltage when braking hard.

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or a new vesc, considering he shorted it out.


i ran motor detection after swapping the phase wires on either side and got the same result… is it safe to say the motors are dunzo? and the vesc is still good?

VESC is done. Motors might be salvageable.

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Best solution to this problem is to buy new battery, vesc and motors… pretty much all the most essential parts.

There goes the merit of the cheap flipsky parts for starters.

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yeah i guess that makes sense since it doesn’t matter which motor is connected to the can bus side. you think the vesc could be causing the over voltage issue too?

damn so pretty much a whole new board eh? she had a good five rides):

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Thinking out loud here, is it possible that the loose XT90 battery connector may have prevented regen from going into the battery, and thus built up in the ESC and broke a side? That might explain the over 100% read when braking, since it wouldn’t actually be reading the battery itself from poor connection. Same with the drops from acceleration - there’s too much resistance from the connector.

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