Brand new 75200 stopped after 20meters of test drive.

Brand new out of the box makerbase 75200. Plugged it in, did the wizard, checked every parameter, checked all the values, made sure everything was working correct. hopped on the scooter pressed on the gas, it ripped like hell ( like it always does ) but after letting off the throttle the motor started braking up real bad like it was trying to regen break and after stopping and thinking " well thats probably not good ", sure enough it wasn’t. It wont power on anymore. No leds, no voltage ANYWHERE, no buzzing, not connecting to anything. WTF!
I opened the casing up to see if i really burned something but nothing? motor doesn’t spin free even without the battery connected, only the motor phase line/hall lines connected to the controller. spinning the wheel feels like its still trying to regen break. please for god sakes tell me someone knows how to quickly fix this. i am very sad because this is not the first time. I had a 75100 which worked for 3 days and 3 small rides before basically doing the same thing. the motor is brand new and there isn’t problems with that.

Does the vesc show any faults?

The motor may be brand new but so is the 75200

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no, i cant even connect it to the host pc.

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i did all the wizards and setups properly making sure to set every value acordingly and poof that happened

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It won’t even connect so u can look for faults?

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no. as i said, it doesn’t power on, no leds no buzzing no nothing. unfortunate.
I believe i bricked it by accident -_-

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Yea I just wanted to be sure.

I seen recovering some bricked vecs but haven’t seen 75200

https://www.vesc-project.com/node/2688

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What did the vendor say?

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if you disconnect the phase wires, does the motor spin freely again? (probably)

if you touch the phase wires together does it feel the same kinda drag/“regen” as when plugged in?

if so I’d be worried the ESC probably internally shorted. maybe inspect the vesc near the output FETs a second time to see any burned something you might have missed?

Get a replacement from the vendor?

what kv / voltage / gearing are you running?

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i am running a 5kw hub motor with 400A something peak. i checked the phase wiring stuff and when i disconnect the lines from the controller yes it spins freely but when i connect blue and yellow it starts spinning with drag/regen. but even if i disconnect it from the controller and just take the motor phase lines and short blue and yellow without any power still the motor spins with drag.

i checked the board and opened everything up… I cant find nothing thats shorting smh…

im running 2x 60v 20ah batteries.

i contacted the vendor but i dont seem to be getting a new controller. as they think its my own fault. Okayyyy, but wtf did i do???

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im here wondering if maybe it bricked itself when it started regenning and my batteries were full at the time etc that maybe it broke and left itself on regenning. thats why it shorts every bms and everything i plug it into. maybe ill just wait till my st link comes in the mail so i can try to get it to boot up finally and see if thats the case.

Honestly ive messed with these vescs so much that for me seeing them brick themselves has to be my side of the issue. wrong firmware/hardware.

logically thats the only cause i can think of is that is stuck on regen and wont take power in cuz as soon as it gets it, it pushes it out at a insane current. making my connections literally melt with a flash.

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this sounds like some of the the FETS are blown short.

I wouldn’t call it “stuck in regen”
the FETs act as littles switches. the controller turns them on an off very rapidly in patterns producing currents in the phase wires that either act as power or regen. you can break the switches in an open or closed state. they seem to be broken closed.

one way is to overcurrent the ESC, either A) from the controller being faulty and not up to it’s ratings. or B.) spiking currents too high.

The vesc has motor current limits, and motor current absolute max limit. the way it controls current, is by watching how much current is going through, if it gets to high (passes motor current max) it starts reducing the amount of time it keeps those switches open. (lowering duty_cycle) to hopefully reduce current in time to keep things safe. if it notices it hit abslute max it will shut off.

if you were to set those settings to high. you will instead smoke the ESC.

makerbase 75200 reported limits:


[ this could be battery current and not motor current i couldn’t quickly tell ]

what did you set motor current max and motor current abs max to?

more subtly even if you set those settings correctly, if you were to pass those settings to quickly, you will also smoke the ESC.

for example If you were to use a really high kv motor, or in general be geared for some really high top speed. (from voltage, gearing, kv, ) then when you ask for low end torque, you need more current to get that torque at the wheel, and this can spike currents faster and pass the limits too quickly for the controller to adjust (max current) or shut off safely ( abs max current )

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i have 60v and a single 11inch hub motor.
About the current. it wasn’t set too high i think like 140A and absaloute max abt 240?
but the break current was only set to like 20A something. i usually run more but i read there could be issues with it. before i ran like 60A but decided im gonna run 20A on my first test run. My usual current is like 160-190 at times and i rarely slam on the throttle just cause when i might need the power then its right there.

Okay, lets say the FETS are blown or 1 is blown somewhere.

  1. why is there no sign of failure on the board?
  2. Brand new controller?
  3. this isn’t my first time with these controllers and ive had great success but just my last two have been a pain in the khm khm…

My questions have all lead to the same thing as you’re pointing out that the FETs might actually be blown.

edit: when i went on my first ride then i couldnt get speed at all up to like 20kmh as the mottor was bogging or something like that. I was like okay well for some reasons it doesn’t like going slow? so ill just press on the gas a little and see if thats alright. it was, untill it wasnt. It ripped like hell and i got excited and let off the gas and there it went. it was like the motor was trying to spin backwards while i was going 40-50. real scary tbh.

I am just gonna wait on my stlink and if that is no help then i am going to take out a loan and buy 5 new controllers because 4 of them with my luck will break ;/
real bummed out…

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yeah that’s a puzzle. I think they can blow with little outward signs. but they most often blow with outward signs. so idk.

tho it dragging the motor when they are plugged into it with no other power, would be a pretty good sign the one or more of the FETs has failed closed.

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Yeah, its a good point. I hope it hasn’t happened but i just got a text on my phone that my stlink has arrived. going to mess around with it today and praying its just some stupid firmware error. bismillah

got my stlink. board booted up everything perfect still doesnt take the battery in. + and - are hard shorted somewhere or idk whats going on.
anyway speaking with the vendor they were kind and understanding enough to ship me a new board.

THANKS FOR ALL THE SUPPORT AND I WILL HOPE MY LUCK CHANGES FRYING THESE SH*TS

respect.

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What kv are you using? Ime vesc doesn’t like low kv.

that’s also a sign of blown closed FETs.

the FETs are switches arranged in such a way that they connect the battery to the phase wires, in various combinations. so if the right combo blows closed. then you get shorted phases or shorted mains or both.

Maybe you’re geared too high?

what top speed are you geared for? you can use the esk8 calc.

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How dangerous is this for starting a battery fire? I’d like to skip the fuse between vesc n battery thinking a typical estate battery is powerful enough to blow through a short before a battery fire could happen

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I know the manufacturer probably said this, but voltage isn’t really a relevant measure at all. The real specs of the motor will be in Kv (not to be confused with kV) and current and maybe maximum rpm (bearing limits).

The “60V” here is essentially meaningless.

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