Hello gentlemen,

I equipped about 3 Efoils now with Trampa VESC6 and I’m a big fan of this controller. At my recent build I got this fault the first time. The VESC is a brand new one. This failure is always hitting in if I go full throttle and while I’m foiling (but not in the starting (lift-off) phase). So it seems that it only occurs with high motor current and high erpm at high duty cycle. If the fault happen I need to restart the VESC to go again.

-I did the FOC detection with the wizard as well with the manual detection
-I played with Motor Stator saturation compensation
-I tried BLDC mode (motor stops always at 75% throttle gas without showing a failure)
-I’m sure that the signal of the remote is stable

My Setup:
100kv 65151 Flipsky Motor
12S10P Samsung 30Q

Motor : 1
Current : 116.6
Current filtered : 127.4
Voltage : 49.27
Duty : 0.910
RPM : 9245.1
Tacho : 270418
Cycles running : 204445
TIM duty : 6111
TIM val samp : 3360
TIM current samp : 3360
TIM top : 6720
Comm step : 0
Temperature : 53.58

I logged with Metr while it was happening:

This is my motor settings:


@Trampa: Could you please give me support on this.



Not familiar to much with this error , but you tried to increase positive ramping ?
You also loose 2v during this phase ( voltage sag?)in your battery pack , always the same config 10p , same wires … with other setup ?
Your motor gets stuck at max setting 120A ( 94,7A batt) just before the error
May be set your batt at 90A ?

Hey @Alexandre thanks for the fast reply!

Why you suggest more ramping time? I press full throttle and after let’s say 10 seconds, if my duty cycle is more than 90%, it shuts off. While I’m starting with full throttle and 120A the fault doesn’t occure.

Wire length are almost the same then at my other Efoils.

Haven’t tried less battery amps yet but I need the full power for starting because my Board is ultra short (120cm).

Maybe try an older firmware?
Can someone post his FOC detection settings for that motor?

Ramping time at 0,9-1ms works on start to limit abs fault , you could it a shot for your problem , it mights give a bit more time for the battery and slower voltage drop
What I notice is that the motor doesn’t run very well when it gets stuck at max amp , I prefer to limit by the battery amp rather than motor amp for max speed
Older firmware is a good idea

For start : motor max amp count more than max batt amp
For top speed : both depending on duty achieved

Silly. I rather limit erpm to limit Topspeed, when my son is riding.
If i limit battery Amps, my vesc sometimes Drops a fault and shuts off instead of only limiting.
For me, i have bad experience with limiting Battery Amps

Which fault does it show you?

I dont know, foilio doesnt get my handy on board :see_no_evil:

Limited at 60A for easy cruise , and 90A for more fun , no problem on my 75/300

But erpm may be better indeed

Are the other setups identical? Usually I would expect the fault top occur at max amp draw, so during startup.
Your motor current is 120A short time before the the DRV fault kicks in. The metr log file is not catching the spikes, since the update rate is very slow. I would make logs using vesc tool, since that gives a higher , actually usable resolution.
Probably you loose sync and commutation is not possible any longer. I guess that the stator is saturated at 120A and the motor is is over it’s limits. There is probably even a higher Amp spike occurring. You should try and decrease the motor amps a bit. The other thing that might play a role is motor heat. A hot motor has a higher resistance. The resistance value in the VESC needs to be ±5% accurate. Once the motor is warm it might be out of that scope. You can try and increase the motor resistance value by 2.5%-3%. The combination of increased resistance and slightly lower motor amps might resolve the issue.


Thanks @Trampa I will give it a try. A lot of users using this motor with a VESC successful @ 150A motor current.
Here is another log with drv faults while I wanted to start:


Last data is 127.3A and considering the slow update rate and sample density of the metr, it could also be higher. Do you run the no HW limits FW? The DRV protects itself and shuts down.
You can try and do motor detection with a warm/hot motor and the compare the results to ambient temp detection. Is the resistance differing more than 5%? You have to be quite fast and do the detection before the motor cools down a lot.

Use a hotgun for heating up, and you can take your time…

Yes I run the no limits fw. How dangerous is this fault? Is there a chance to damage the Vesc? I can run the motor at full speed while pushing it against me.
What is with the idea flashing an older firmware?
I also will shorten the phase wires from 1.1m to 0.9m

Flashing older FW makes no sense at all. You can set Duty Cycle Current Limits to 85% or 90%.
This will ramp down the power at full duty cycle, so you will get good statup power but decreased power at full RPM/ full duty cycle.


@Trampa can you tell something about the displayed faults?
First it seems strange that both status/fault registers are triggered at once, and with them every single possible fault (is the OTW really at the same time as the OTSD? all possible faults happening together? or something wrong in the software/output/terminal?)

In the datasheet of the DRV8301 e.g. the OTSD is described as the Overtemperature Shutdown and the OTW as the overtemperature warning is this possibe due to insufficient cooling of DRV or due to not good soldering of the DRV GND pad in first place?

Also the fault typically happens only after some seconds of full speed at max current (like after 10-20secs) which also points more to the temperature thing than onto a saturation or tracking problem (which typically happen at low RPM high current) or real overcurrent (since the MCU abs overcurrent fault never kicks in).

What possible risks come with setting the OC_ADJ higher? From 16 to like 17 or 18, theoretically the OC flags should trigger then later or even disapear, right? How good are the chances of frying the VESC?

@Trampa: I lowered down the max. duty cycle to 90%. The DRV fault doesn’t occured that often then. But I also had an DRV fault @76% duty cycle. So that’s not really an approach.

Looking forward to your answers on @Giga s questions!

Did you do the measuring of the motor resistance a.s.o.? You could use the default VESC values instead of measured values, as it seems to run more stable there. Does the fault occur on FOC Mode as well? Try to set the motor max amp to 115 and absolute max Amp to 160 and see if the fault occurs again;-)

A.s.o.? Tried BLDC as well. What you mean by running with “default” settings?

The VESC default setting for the motor. just changing the amps limit and rest leave on default…

I raised the motor resistance about 1 mOhm. It seems to help a bit. With this modification @kotnascher could achieve to run a few seconds at full speed on my board. After that he nosedived heavily @36kmh.

So unfortunately it’s not fixed yet and it’s quite shitty to reproduce this fault… Do I need to send the VESC back to you?