this might not be the most elegant way, but after a ride I leave the board on, plug it into vesctool and run the “faults” command in the terminal, then it shows every fault since startup
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Perfect! Thanks for that. I can add a button to my dashboard to do that too.
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Did you reduce the regen current (negative battery current)?
Is there some associated event with the major DRV faults or does it just seem like it happens no matter what after 10 to 15 minutes?
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yes, battery negative is -4.
I haven’t been able to find out what triggers it yet. I guess I could maybe try riding without braking to see if I can still get that fault?
seems I’m able to recreate it very quickly, rode for 2 mins, did some braking (at only -4A) then hit the throttle hard a few times.
And even with 4 caps I’m still getting over voltage on braking.
currents: 60,-30,95,24,-4.
maybe the delta between motor current and battery current is too high?
The following faults were registered since start:
Fault : FAULT_CODE_OVER_VOLTAGE
Motor : 1
Current : -10.3
Current filtered : -9.4
Voltage : 57.94
Duty : 0.223
RPM : 15898.5
Tacho : 80677
Cycles running : 4495
TIM duty : 1875
TIM val samp : 4200
TIM current samp : 4200
TIM top : 8400
Comm step : 0
Temperature : 30.64
Fault : FAULT_CODE_DRV
Motor : 1
Current : -32.1
Current filtered : 7.6
Voltage : 42.77
Duty : 0.595
RPM : 27536.3
Tacho : 186615
Cycles running : 1791
TIM duty : 4999
TIM val samp : 4200
TIM current samp : 4200
TIM top : 8400
Comm step : 0
Temperature : 32.90
DRV8301_FAULTS : | FETLC_OC | FETHC_OC | FETLB_OC | FETHB_OC | FETLA_OC | FETHA_OC | OTW | OTSD | PVDD_UV | GVDD_UV | GVDD_OV |
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Just went for some hard riding with my longboard (13s, pneumatics, dual keda motors). I’m on 75/-75 motor current 120 abs max, 99 -60 battery. So far the focers are doing really well, had to reboot them when i stopped and accelerated hard.
The battery is not taking it very well. The focers are in a aluminium enclosure, cooling is working really good.
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@alwaysmohawk It’s really odd to me that you’re experiencing such high voltage spikes when braking even when your pack voltage is at 42V. This is with your LiFePO4 battery right? Does it display this behavior with a typical lithium ion battery?
@doomy Wow that’s some tough conditions on them FOCers!
Correct me if I’m wrong but it seems like the FOCers never got above 45C! That’s proper thermal management right there.
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They only get barely warm, the motors a bit more. Its 13s liion, old ebike 13s6p battery. I will up the amps to 85/-85 next. Its running in FOC but i have the impression it has less punch than in BLDC.
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i only have the one lifepo4 pack.
i just spent the past 2 hours putting together another board. this one made it about 5m before “fault code DRV” that won’t clear.
it must be either a problem with my battery, motor, or every DRV. I’m no expert, but man, i would put good money down that I soldered it as near to perfect as possible, i really took my time. no bridges, plenty of heat, brushed any flux off with toothbrush and rubbing alcohol etc
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Hold up you’re running these at 13s? That’s damn impressive.
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replaced the DRV with one from Digikey, now i’m getting:
The following faults were registered since start:
Fault : FAULT_CODE_HIGH_OFFSET_CURRENT_SENSOR_2
Motor : 1
Current : 0.0
Current filtered : 0.0
Voltage : 45.74
Duty : -0.000
RPM : -1.6
Tacho : 1
Cycles running : 0
TIM duty : -1
TIM val samp : 4200
TIM current samp : 4200
TIM top : 8400
Comm step : 0
Temperature : 34.49
should i just start a separate thread with all the issues I’m having? lol
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Are you using a BMS that could be stopping or choking current fed back to the battery?
no, just straight to battery
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I’m not going to have much time for the rest of today to help and I’d rather help you on a separate thread or PM.
The high offset current sense fault means the output signal of one of the current sense amps in the drv is not right. I get these when it’s not soldered properly
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Once yall have it sorted out (if you get there) you should compile it into a TSG for the Github.
Edit: Or give me the transcript and Ill start a TSG for the Github 
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I’ll PM you.
I have 4 boards left (that I haven’t touched). They cost me $40(CAD) a pop landed, I’m willing to let them go for whatever offer I can get. So far I’ve spent $160 in cfoc2’s and I have nothing to show for it.
If I don’t get any offers and anyone just wants them PM me, might as well get them to someone that can help out with testing.
Thank you to everyone that helped me out.
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My FOCers from @alwaysmohawk arrived today. Just got one put together, and it seems to regulate 5v just fine. My testing procedure was to slowly increase the voltage supply from 5v and measure the 5v+ rail as I increased it. The board produced an audible hum up until ~8v where it became silent and the 5v+ became stable at about 5.20v. I’ll report back once I get both FOCers fully assembled and we’ll see if I run into the same issues as @alwaysmohawk. Fingers crossed 
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Second FOCer regulates fine as well
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Yeah the DRV needs at least 8V or so to operate. This is expected behavior.
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