VESC - FAULT_CODE_DRV. -->discovered later on: JUST FROM STANDING STILL START <---

Hi @Yecrtz, what settings do you need to look at?

meanwhile here are some

also strange thing is that when I use the arrow key to spin the motor, it sometimes works with left/right keys while it never works (FAULT: DRV) with up and down keys

Looks like you just used the defaults settings.

Mostly, they look like a good starting point to me

That vesc is known to only be good to 50a continous for the battery max setting, you have it set to 60 which is prolly caused the issue

My mistake but It is unlikely that I got up to 50amp… I was going very slowly fpr the test

Plus I volounterly stopped my riding as I said: no smoke, no burning. Just silently no more going after reconnecting the power. I think that if I had drained to much current I would have fried the Vesc and I would have noticed. Right?

UPDATE:

if I give it a little “jump start”, a little initial rotating speed manually to the wheel, it works: motor spinning and no fault code.

The motor is not spun and I get the FAULT_CODE_DRV just if I give throttle from standing still

ideas?

UPDATE 2:

following @goldenHusky suggestion I tried on another motor (a little one, from a quadcopter) in order to exclude motor issues.

Same behavior, plus I was able to start from standing still by very very slowly increasing the throttle. Which is basically the same thing of jump starting on a bigger motor: not asking for to much torque(and current?) at the beginning. I think…

ideas?

UPDATE 3: I tried one more thing, same motor another ESC capable of 7s tops on a desk power supply. I was expecting the motor to be spun from also standing still, but no… same behavior: motor starts only with a little help.

so, RECAP

  • TB VESC + TB motor : no starting from standing still and COFE_FAULT_DRV. It starts with some initial kicking
  • TB VESC + little quadcopter motor : no starting from standing still and COFE_FAULT_DRV. It starts with some initial kicking
  • old ESC + TB motor : no starting from standing still. It starts with some initial kicking

:thinking::thinking: In this way I can’t exclude failure neither in the motor as @goldenHusky suggested nor in the ESC … right?

it’s possible you don’t have enough thrust with your gearing and only one motor and 60a to overcome your stationary load. (you mention the problem only occurs using the throttle from a dead-stop)

ways to increase thrust:

-increase your gear reduction ratio -use 2 motors instead of 1 -increase the motor amp limit

or is it possible you have a battery management system which is causing power cut-outs when you exceed X # of amps?

what’s your tire size and gear ratio?

Hi, gear ratio is 2:1. amp limit is at maximum bearable by the VESC. Also it was working with current setup, so no, there is no battery management system involved

Problem is that I have the same problem with free motor shaft, no load/weight applied.

2:1 seems quite low for single-motor drive @ 190kv. tire size?

one problem is that the motor is in sensorless mode meaning that you need a kick start to get the board going. The load you have on one motor is greater then the amount of torque needed to get you going. That motor can be ran in sensored mode as it has the sensor wire. Maybe to much amp build up and and blew the vesc. Also the -40 bat regen is really high are you using lipo or li-ion batteries.

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@professor_shartsis 70mm diameter

@briman05 yeah I know about the sensored mode, problem is I don’t have the adapter cable for the VESC. I need to find some free time to do it myself… after I have found which wire is which of course…

Thing is, as I said before, I need to kick it start also with no load on the shaft, to be clear: belt removed and test bench

Lipo batteries, do you think I need to lower it down? how much?

If you take the belts off and put it on the test bench your motors should spin freely without any load on them. I’m not sure what your settings would be for the lipo batteries as am using li-ion It looks like you are using the vesc tool that should do the calculations for the cutoff start and end for you. What is your battery parallel because you need to figure that out in order to set the right regen for your batteries.

If you take the belts off and put it on the test bench your motors should spin freely without any load on them.

yes, it should… and it did, once upon a time…

I’m not sure what your settings would be for the lipo batteries as am using li-ion It looks like you are using the vesc tool that should do the calculations for the cutoff start and end for you

cutoff start and end are in terms of voltage and set to 12s settings (40.8 and 37.2).

What is your battery parallel because you need to figure that out in order to set the right regen for your batteries

I’m with 12s1p, 5800 mAh, 25c. Saying here that "The safest charge rate for most LiPo batteries is 1C, or 1 x capacity of battery in Amps. ", I set it to 5Amps, just to be safer.

Do you agree?

Maybe ask @Namasaki he has alot of experience with lipo batteries

I’m using 5000mah 60C Lipos that are rated for 5C charge. I charge them on the bench with 5a and my Vescs are set at -10a each for regen charging.

I would recommend that you check the specs on your Lipos for thier max charge rate.

one thing I do know is it’s “difficult” for a controller to spin a motor from a standstill without sensors… this is partly because it uses the back emf voltage produced by the spinning rotor magnets to “know” the rotor position & which phases to energize & for timing exactly when to commutate… so without sensors or back emf voltage from a spinning rotor, my understanding is at standstill the controller “blindly” energizes phases in sequence in an attempt to get the rotor to turn so that it will generate back emf voltage which then gives it the timing information for subsequent commutations… if the load is too great or not enough back emf voltage is produced to get a good rotor position reading while it’s “blindly” energizing phases at start-up, perhaps it generates a DRV error. this is just a theory, hope it helps.

I’m having this EXACT issue with a brand new setup. 10s4p Li ion with a 10s BMS VESC and a 6364 190Kv motor. It also hits full speed at half throttle…

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