Should be closer to 0.010 ohms for a motor winding. Sometimes multimeters can’t accurately measure that low. If you have a LCR meter you could measure inductance and see if it’s similar. A shorted winding would have a very different value. But yeah the hand test might reveal something. Do you have another motor to plug into the esc and see if it passes detection?
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Yeah, my meter is made from cheapesium. I can do the hand test and detect a TB6355 tonight
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More results (???). Shorting each pair of motor phases increases choppy drag, shorting all 3 adds more drag and makes it smooth (as normal), when unshorted the weaker, choppy drag remains. Shorting the red and yellow pair feels a bit different (less choppy, maybe weaker), so the fault might be there.
The ESC powers up and connects to VESC PC just fine, then I wired in a (known working) TB6355 and my precharge resistor rewarded me with 
more magic smoke as soon as I plugged in. So nevermind about detection I guess.
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Jesus, your thumbnail game is on point, besides the fact that this is unadulterated diybuilders pron. don’t know how I missed this till now. 
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Thanks, you’re the first one to mention that.
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So @jaykup you seem like a knowledgeable fellow, is my gear haunted or what
Do I need to call a VESCorcist
Clicked to see what you did with an 80mm x 100mm motor
(reads thread)
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So you have the ESC connected to the battery using a loop key port, and you plug in a loop key with a big resistor instead of a traditional wire to help charge the caps, then you unplug that and plug in a regular loop key, right? This is needed because XT90s cannot handle 20s?
With no motor connected, you plug in the precharge, then loop key and it powers up and connects to the VESC tool, but when you turn it off, plug in a working 6355 motor, then try to power it back up the precharge resistor starts smoking?
If you can power up the VESC and configure it, try to reset all defaults to make sure the throttle input isn’t erroneously telling the VESC to put power into the motor or something.
Can you unplug the ESC from the battery and plug it into a bench top power supply that limits current (or a low current charger if you can measure current with a meter) to see if it’s drawing normal current with no motor, and what current it draws with a motor attached?
An easy way to use a multimeter with that setup is unplug the battery, plug in the charger to the same port, then use the multi-meter in 10A dc current mode and put the leads in the board side loop key port.
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Correct except for the part where I unplug the precharge, that would power down the controller and defeat the point. Didn’t get to the regular loopkey anyway though.
I have a 5A charger, is that low enough?
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Could be a blessing in disguise your ESC fried. I just saw your other thread with the wheatstone bridge weight distribution system. Way too late to warn you about that catastrophe but what happened is one of your strain gauges broke. I didn’t have time to watch your build vids so I can’t say I know how you setup the code. The big red flag you unfortunately were not aware of was the weakened responsiveness and unbalance that it seems you compensated for in software. In my build I used insanely high sampling and processing rates so the motors would freak the fuck out ( make terrible clunking noises as they rapidly switched directions) when the system read the unstable voltages from the amps.
Anyways, the reason I’m posting, you absolutely need a tether jetski killswitch. Attach it to another open pin on your VESC and have your coding dude add the code to cut power when the tether is pulled. I think you have a good idea how terrifying it is to have your baby leave you at top speed and hoping it’s going to hit a wall and not a car or a lawyer. You have now entered the world of mechatronics and safety is everything. Runaway motors fucking suck, just ask a lathe accident survivor (not too many of those people around). Here’s the aftermath of my 4WD @NoWind 8085 build attached to a physical tether that kept the board from flying down the road at 50+mph. I had to fight the board burning out on the front two wheels while I opened up the pelican case to hit the reset button on my microcontroller. It burned out on my leg (which I didn’t even feel as I was so pumped with adrenaline trying to shut the monster down) and flung a shitload of dirt in my eyes. This is my sixth prototype of self balancing via weight distribution over ten years and I thought runaway conditions were over and done with on prototype four and five. Not sure enough that I didn’t keep a physical tether. Glad I did or I’d be out 8K. More if it hit someone or something. I have now attached a jetski tether and urge you to do the same before any further testing. Sorry for the rant I’ve just had some serious PTSD from prototype two. That thing loved runaway conditions lol.
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PS, don’t use a loopkey as a tether to cut power or you might burn up your next controller. If you really wanna go that route then install a diode so that the power from the spinning motor will at least be able to go back into your battery pack, not spike and blow your mosfets
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Ok, thanks for the story but I’m using a conventional twist throttle now just like every ebike? Wired connection to the vesc and everything. And I have a wire strapped to me that cuts the throttle signal to 0V when disconnected.
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Yea looks like a safe setup just wanna keep you cautious. Complacency is a feeling I know all too well in my builds. I’ve had some hilarious fails and some scary ones. I thought I had all runaway possibilities eliminated then I burnout on my leg. I have no idea how you have the electronics set up tbh but I believe the VESC now supports a killswitch so you may not even need to write any code. I seem to remember seeing it somewhere. I send commands through the UART and do all the processing on a microcontroller so can’t tell you for sure it exists. Sounds like you have a good grasp of what needed to be changed on this build. Wish I knew how to make badass composite designs like this. I just bolt aluminum bars together like some sort of savage. If you ever wanna go back to a four wheeled strain gauge design lemme know cause I’ve got the BOM and portable code that’s made some extremely reliable and responsive systems. I like how you went a completely different direction. Shows some serious ingenuity and gumption to start from scratch like that.
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Thanks. I think I’ve had my fill of strain gauges, but if you ever want a LegStick™ let me know.
My setup is just that the analog output of the twist throttle goes to the VESC ADC. Having a kill command wired onto the same loopkey that kills the twist throttle would be cool too.
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Yeah 5A is fine, and it can be lower voltage too (12s) as long as the vesc voltage settings match.
You’re famous among the local euc riders. They’re spreading clips of you from that one ride you showed up to.
(I think it was you. Helmet and body armor look the same, plus Who tf else would it be haha)
Next time give me a heads up!
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Oh nah that’s the other 6’7" dude in NYC with a carbon fiber bikeboard 
Lol I was commuting at the time and randomly linked up with a couple EUCs and a board for a few blocks before I had to make a turn. They seemed a bit too hooliganly for my taste though 
I’m down to go riding though, I understand there’s meetups at pier 76?
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Yeah there was one today for a board demo. It’s the end of the riding season so there isn’t much, but next year I’ll be hosting a bunch of stuff. I’ll loop you in for those.
Those euc riders are a bit… Extra. Absolutely.
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Sounds good
Their aesthetics were very tokyo drift for sure, I was more worried about the squid stuff though
I wonder if you know how we do in NYC, fast and furrrrrioooussss
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