dude… the motor appears pristine… the inductance loops equivalent… it may be spurious… but did you do a continuity to ca/bearings/shaft test… the impedance check says no… but I’d still check…
my k00k approved guess is…
your motor is gUUd
continuity tests from each phase lead to bearings, ring on sensors, backs of stator windings (not sure what that’s called). any part I could prove conducted between my probes itself. showed no continuity to the phase leads.
inductance does seem off though
testing inductance on 3 other identical mortors I get values from 20-27 µH
testing this motor I get 50-52 µH
that’s leading me to suspect that high reading means something. the smaller value is close to double the vesc_tool recorded value which could make more sense than quadruple.
still considering that motor suspect. curiosity wants to find out more but I think I’m at a dead end.
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ooo thank you. i thought it was some type of seal to prevent dust getting to the bearing, nvm me haha 
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The only thing you will notice between FocBox 1.6 and 1.7 is that 1.7 will heat a tiny bit more. It uses mosfets with a bit higher internal resistance.
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I think it’s a combination of not noticing the fault and maybe resuming motor control when the circumstances that caused the initial fault are still present.
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I should add to this thread that this setup is a 10s
Thermal pads […] are one-shot solutions only. You have to replace the pad if you ever remove the heatsink from its mounted position, because the heat of the operating CPU will have caused the thermal pad to conform the top. So, once you move the heatsink there will be new gaps between the surfaces. So never forget: If you dismount the heatsink, replace the thermal pad and remove all debris.
– https://blog.arctic.ac/blog/2015/07/23/thermal-pads-or-thermal-paste/
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went ahead and got this stuff to act as replacement thermal pad inside the focbox 2mm thick 8 w/mk conductivity.
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You have to do that with thermal tape and thermal grease too. I think that’s just part of the process with thermaly conductive materials.
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yeah the advice is generally “don’t reuse”
However, currently I have it together and I “did reuse” the thermal pad. and the two focboxes seem roughlyt the same. but I’m going to do a metr recorded temperature run or two before to capture current state of things before I switch out the pad.
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If your careful removing the pads you can get away with it. I have used 6in blade from a glue scraper before.
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later half of my ride. metr somehow didn’t record the part where I was heating things up.
anyhow the two mosfet temp readings are mostly 1° C apart. ocassionaly two. (but resolution is in degres so it’s probably 1.5 or something ) I think this is within the realm of normal.
Of the two I don’t know for sure which temp reading i the primary but if I assume it’s the first one, then the slightly lower temps are with the 1.6 replaced focbox and not the untouched 1.7 original.
Damnit. DRV fault on the remaining focbox. ???
first 0.5 km of the day. 
No idea if this is related to the first problem but continuing here because it’s suspect. board triggered a very similar feeling problem a cutout with the funny noise and then some drag. got home and found DRV fault on the secondary focbox.
No faults registered since startup
The following faults were registered since start:
Fault : FAULT_CODE_DRV
Current : 150.5
Current filtered : -33.7
Voltage : 36.39
Duty : 0.753
RPM : 33796.9
Tacho : 171975
Cycles running : 99717
TIM duty : 6326
TIM val samp : 2
TIM current samp : 4200
TIM top : 8400
Comm step : 0
Temperature : 43.39
I have zero clues at the moment what a DRV fault is and what causes it.
METR did not seem to pick up this fault though. I think it’s supposed to pick up faults from the secondary over CAN at this point. I think I’ve seen it do this. but it didn’t.
here’s the record from it happening.
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I’m so paranoid now I’ve done something that’s going to blow the other focbox now that I got a DRV fault.
The only thing I can think is that I raised max motor amps up to 80 from 70 as an experiment to see if I could tell. I could feel the off the line torque only for a moment before battery max amps kicked in. I didn’t think the motors were running hotter than usual. but maybe this period damaged both motors.
I think next I will re detect motors and see if inductance or anything else seems to have changed.
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Old:
New:
Initially I got a reading of 8.?? µH for inductance. and I tried detect a few more times it seemed to narrow in on numbers around 13.?? µH
for comparison, I want to get this motor from the secondary side unhooked and check it with the inductance meter.
Also want to get that old replaced motor from the primary side hooked up to a focbox to do detection and see if it reads double the inductance via vesc_tool the way it did on the inductance meter.
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well, I’m going to need to sell this board soon.
So I think I need to cut short experiments, and just replace the focbox and the motor on this second side.
because I still have no idea what really causes DRV faults other than “DRV chip going bad” and “shorted phase wires” and I don’t see any obvious signs of that.
but that will leave me with these parts that are suspect.
Is this top right mosfet blown?. I cant tell not bubbled iust discolored. Did a.motor test amd now one motor jerking back an forth one spin normal. Nothing else changed. 6374 battle hardened. 80 motor max 45 a battery 12s4p. Idk. Dont gey it. Silicone in jst.hall sensor ports. No loose connections. Idk allem wrench pointing to mosfetUploading: 16020113281492749727536685256396.jpg…
And will these work??? If so?? Friend Don said its Blown. Double checkin here
The top right fet is one of four parallell fets for the antispark circuit. The four ones that surrounds the red batt+.
Your problem is somewhere else
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Damn. I unplugged the halls and it works again spins normal both wheels. I ordered another Unity anyways off massivestator a bit ago. Just to have here. Idk what im looking at wirh these very much. My friend Dons like thats a blah blah component yada digikey bubba fet something. 
. Thats All I hear. Mosfet. I know what those are. I can make one on kicad. But dk what im making. Did photoshop and illustrator for 25 yrs now. Looks the same to me. Just circuit board pieces instead of brushes. Idk. Learning. Got decks got drive trains learned composites amd suck at it!!! Hahahaha. Alan Chaus the Man!!! Haha. I gotta learn the speed control just because!!!. Inhave to make one. And not a practice one. A badass one!!!. Hahaha. Even if Its only one!. Like learning a song on a guitar that’s really challenging. Or the newest rubiks cube. The speed controls got me hooked. Its something I dont know. And i want the knowledge like gollum from loard of the rings. Hahaha
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