Have you tried shouting at it yet?
Must be something wrong with h/w now if you can’t swd
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still fucked
it has heard some colourful language
and yeah thats what me an jaykup think, but i can’t find my multimeter to poke around with it
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f 
on the bright side, at least it’s not the fiery kind of hardware problem
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The thread name being “100v dual ubox fire” gives the incorrect impression that most of the issues are the 100v version.
It looks like it’s really the 75/300 version that is fire prone. I’m not sure the 100/250 100v ubox deserves a firey reputation, or if it’s just an unfortunate association with the 75v version. Maker x seemed to see more exploding escs on the D series when they were on 75/300, before they switched to 100/250.
@jaykup any thoughts on explodyness of 75/300 vs 100/250 designs?
OP - 100v
@Skyart - 75v
@BigBen - 75v
@Pickled_Monkey - 75v
@whaddys - 75v
@Tasventouras - 100v (post says says: case of being a guinea pig stuck in the firmware mess in the early stages)
@Halbj613 - 75v
@Katarsis - 75v
Reddit user - 75v (admits to using wrong firmware)
Ubox single - 75v
@JesseM - 75v
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75v here
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The difference between the two designs is mainly phase shunts (75/300) vs low side shunts (100/250)… and in a perfect world where all other problems are either solved or the same, the phase shunt versions should be better. It’s also worth mentioning that those are reference designs. Companies like Spintend, Flipsky and MakerX all put their own spin on it… with different components and layouts… and that can make or break a controller.
Turns out reliable VESC hardware design is pretty complex. A motor controller is a simple concept, but there is a crazy amount of small details needed to make these things work, especially when running that much current through a relatively small device. Lots of seemingly innocuous choices that the designers make can have huge unintended consequences down the road. Then you have to factor in all the things the controller will experience in it’s life. Frayed and shorted phase wires? Sensor wires shorting against the motor windings? High voltage traveling across the canbus? Power wire touching a heatsink?
It’s really interesting watching the hardware builders on the VESC discord. They blow up a lot of controllers, but learn a ton in the process and come up with some really cool solutions. There are also a lot of really talented designers throwing out ideas along the way. Unfortunately the normal big name makers don’t share their VESC build logs with it’s successes and failures, so it’s hard to know what is going to work well, and what isn’t. Usually all we get is a few pictures and a promise.
I think this question ultimately leads to the real question - which VESC is not going to blow up on me? Truth is I don’t know. The DRV wizard said it best. “From Experience I can positively affirm to all of you that I’ve seen on my bench for repair 99% of all type of Vesc base controller!”. That has been my experience too. They all blow up in different ways. Some of it is firmware related, but most of it is small flaws in the hardware design.
I think each controller should be evaluated on it’s own in terms of reliability and cooling… two very important things that we have little data on. From the evidence, it certainly seems like the Uboxs have some unique issues as they all seem to fail in the same way… a fiery death. It could be something as dumb as the positive wire shorting against a heatsink… or the high current pos/neg traces having too tight of a tolerance for reliable PCB manufacturing.
I recently had a great conversation with a design engineer who worked on the ESC design team for a big brushless power tool manufacturer. Turns out they also use DRV8323 chips… and also have quite a few problems with them. I brought a bunch of different VESC controllers with me and we were going over all sorts of pros and cons of the different designs. I brought up one specific failure mode that I’ve been racking my brain on how to solve and he just laughed and said yup… you and the entire R&D team at my work.
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Good point, because it was a joke in the original conversation that evolved I never made my own thread for the list, didn’t really think about the implications of it being in a thread called 100V fire.
Any suggestions for what to do with it? It might make sense to move it to a general thread documenting hardware failures, but the reason I made it to begin with was to double check my own impression that uboxes are disproportionately firey. As above, lots and lots of hardware fails, but spintend seems to be unusually common and destructive, so I think a general thread on failures dilutes that a bit and takes away from the point that they (or at least the 75v) are not really a good recommendation
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+1 to at least rename it 75v, cause that looks to make up 90% of the failures.
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Again though, this is not my thread. It’s a reply post in a relevant thread (that has been thoroughly hijacked, sorry about that)
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Oh haha, my bad didn’t even realize. Hmm yeah not sure what to do in that case
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Yeah, I just created a topic about it…
Didn’t realize it had it’s own thread 
… I’ll move mine here in a sec.
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Ok, so it was probably running something around 70-75 bat and 90A motor per side… But it was like that for about 3 months with no issues and some really hard riding… This time I started ripping up a hill and about 50 feet in the board cut out and then the wheels turned like they were stuck in mud… It wasn’t a normal fault… What should I look for in this autopsy?
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A new vesc lol
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how did your enclosure fare with the fire? salvageable?
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There’s an informal list of fires further up in the thread here, if you want to add yours to it I made it a wiki
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There’s not much to look for, the fets are probably incinerated.
Has anyone seen any reported fires on the BioX version of the Ubox?
Been running one on 16S for a while so just curious.
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