This is the outcome of the detection process.
All is well, but when doing throttle the motor jumps.
This happens also in BLDC.
How numbers compare to the good motor
The motor resistance is different. Bad contacts or broken windings are the cause. The motor will probably detect with different values each time you run detection. These issues are hard to fix.
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Hi Trampa, thanks for the assistance !
Yes, looks like the motor is bad, it was totally new from the box.
I opened it today, but could not see visible defects, no free magnets or anything, the wires on the bottom looks solid (i need to take apart the bottom can part to see more clearly, not sure if it’s doable …) :(,
any other idea ? I’m uploading some photos.
Have you tried running the “bad motor” on the ESC that the good motor spins on? I had the same “jumping” problem on a slave ESC that is partially dead. Thought it was a motor too I was getting weird values but it turned out to be the ESC.
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^
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Which ESC was it ?
Currently I have 1 ESC which is FSESC Dual 6.6 Mini.
I tried to connect the bad motor to both ports 1 and 2 and it acts the same.
The other motor spins correctly on both ports.
Flipsky 6.6. It’s the second time I got a bad ESC from them and I’m not happy with it. Its possible that your ESC has a software glitch and you could try flashing the ESC with a discovery board or a ST-Link. But if you say the good motor is working fine one both ports then I’m not sure. If you haven’t tested the motor by hand and connecting phase wires together to see if there is jumping or resistance then I advise you to do so. Also is the hall sensor plugged in? You can also test hall sensor if that’s f uped.
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I tried to short the phases and do a manual test -> looks like there is a resistance on all combos (a,b,c) - hard to tell if its exactly the same resistance though (by hand).
The motor spins fine when spinning it by hand, no cranking noises or anything inside. I also opened it as you’ve seen in previous pictures and there is nothing “special” inside.
I tried all combinations, running sensored, sensorless, FOC and BLDC. FOC detection goes fine, but the motor spins incorrectly when hitting the remote, BLDC detection fails and the motor is doing strange noises. I tried to switch the phases connectivity to the ESC as well. Nothing. Again, the other motor acts just fine - that’s what’s killing me. Perhaps it’s like a rare situation of bad ESC with a specific combination of motor characteristics - I don’t know yet. In my investigation I intend today to check the polarity of the stators in the motor and perhaps check it with another ESC I will get from a friend.
Such motors are not fixable with ease. probably some windings are broken or a phase wire solder joint is bad. Basically they need to send out a new motor.
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I 100% totally agree, I’m trying to speak with them, problem is - they are in the coronavirus outbreak nowadays in China 
… response times and all service is now broken and slow due to that.
But of course, I agree, new motor should be the solution ultimately.
Such a motor can easily blow up your ESC if windings are broken.
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A friend helped me and tested the motor with an oscilloscope, adding photos of the 3 phases tested with it. The motor was spinning with a driller.
Phase B is the only one that looks clean, WDYT ?
Phase A:
Phase B:
Phase C:
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You’ve got substantially different results for inductance and resistance in the test results u posted above. Different between the green and white. Don’t know which is which but very different. Shows badly there.
Surprised the oscilloscope showed such a clean sine-like wave for the phases as mostly they’re more trapezoidal for these type motors. I don’t know much bout that but ur R and L results say enough to know the motor is not right.
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Maybe u could forget flipsky and rewind it. It’s not hard and sure will be better motor. Since u have one thats good already to compare against be a great test. We go for lowest resistance with lowest kv. Where u live dying to get a hand wound lrk version to compare. And going past that then strip of magnets and reinsert hallbach. If u send me the two motors. I’ll rewind for the closest kv and bet ends a better motor. And I’ll vacuum in epoxy to fix the wires. If u get the sensors off and send them. Just a thought. Better yet u do it
John, where is your preferred source for magnet wire?
Doesn’t matter. They’re all rated to a uniform standard. Can get 200c rated stuff on amazon. Get heavy build maybe to be safe.
But my preferred:
Getting 240c rare stuff. Think it’s Essex brand
I have pounds of stuff I likely won’t use anymore w the new motors. Can do 16awg now instead of 17 for same amount of turns so the 17 awg no use now. Have like 5 lbs.
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You’re saying flipsky are better ? they have high KVs only on 5065’s. I’m far away, so it’ll be a problem to get them to you … 