I recently had my Tronic 250 blow up randomly for no apparent reason (long story - might explain later). I just got my x12 in today (thanks to Tronic for helping out), and I’m about to connect it to the motor. But I was wondering, could my motor have been the cause of the issue, and blow up my x12 too?
If the motor has a short, then yeah it’s possible. Have you tested the motor?
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I haven’t. What would you recommend I do to test the motor? Just a continuity test across the phases?
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No, that should return as positive for all phases, whether or not two of the phases are shorted together. You can detect a short by spinning the motor by hand and seeing if there’s any drag on it, or you can tie the phase wires together two at a time, and see if the resulting drag feels different for any one of the three combinations.
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Definitely. I’ve heard about people blowing up multiple escs before realizing it was the motor that was the issue. 
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Good to know. I’m definitely glad I asked. I wish I had an older Vesc to experiment with first, since I really wouldn’t want to blow up my x12. I’ll see if I can test the motor tomorrow. Thanks for the knowledge!
So I just was able to do some testing, and here are the results: Continuity test came back true as you said it would. When I spun the motor with no phases connected, it had no/little resistance. When I connected any 2 phases, there was a pretty large amount of resistance, but still moveable. Any 2 phases felt about the same. When I connected all 3, there was a much larger amount of resistance, making it very difficult to move at all.
So do you think this sounds normal? Should I just connect it to a Vesc and hope I don’t burn $500? It is a sensored motor but that probably doesn’t make a difference.
Sounds normal, but I’ve also found motors with intermittent shorts that past the hand test, but repeatedly blew up escs.
2 phase short should be choppy, 3 phase should be smoother too
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Yep, I got the same choppy with 2 phases, smooth with 3 as well.
Yea I really don’t like this situation I’m in. I wish I had an older cheeper Vesc to test with first, but the only other option is a Stormcore 100D. Which I’d rather not blow that up either. What would you recommend I do?
Doing an ohms measurement can also tell you something
This is true but keep in mind you need a meter that can measure single digit mOhms. You can also check continuity between each phase and ground (as in the stator or motor body), but I’m afraid that’s as far as my knowledge goes.
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Hmmm I see. So I’d assume you’d want to make sure each phase has the same exact resistance?
U can use the three wire method to get a detailed enough ohm reading but regular multimeter won’t get low enough
Simplest and cheapest is using a 15$ L/C meter and measure the inductance of each phase and make sure they’re close. Have to do it with rotor off.
If a phase is shorted to the core that would effectively be half a short and wouldn’t be a full short unless two phases.
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Thanks for the info, I’ll look into that.
It seem weird to me that shuch a small short could lead to a Vesc ending up in flames. Wouldn’t it make sense for there to be some sort of fault protection? Or is that just not possible for some reason.
Fault protections don’t really stop short circuits, that’s why they’re short circuits. They bypass the intended circuit path and form a short circuit.
Problematic motors can indeed blow up an ESC. However, sometimes an ESC can just fail on its own due to its own problems, be it QC failure, component failure, contamination on the PCB, improper mounting, or any number of other things.
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That’s a good way of putting it. Thanks
Hey so do you think something like this would work well enough to measure the inductance? Digital LC100-A LCD High Precision Inductance Capacitance L/C Meter Te__- | eBay
Works great. I have two.
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Great. Thanks again. Just ordered it