Burnt motor when setting my VESC controller

Hello VESC users !

I need your advices...

I tried to set my VESC controller (Turnigy 50A) and motor (Turnigy SK3 5055) with the VESC tool (new interface).
I was using the motor setup wizard on FOC mode. And when I arrived on the FOC settings page, I entered the R value indicated in the motor specifications (31 mOhms, instead of 15 as a standard value on the VESC tool), then I cliced on the "RL" button to start measurment of resistance and inductance values (see image 5 attached)... and my motor burnt in a few seconds ! The motor is dead, but my VESC seems also to be damaged (see photo).

I have set max current values (50A for the battery, which is a Lipo 4S 10Ah 10C, and 20A for the motor), so I just do not understand what happens. Mistake on my side, failure of the VESC ?
I have made some trials before with the VESC tool (using keypad arrows to action the motor) everything was working perfectly...
Do you have an idea of what could have happened ?

Many thanks for your help !

Jil

Here is a picture of the motor after the incident : a part of the wiring is burnt.

I'm not a motor expert, but it seems strange to me that the motor damage is confined to a spot like that. If for some reason the current applied to that phase was excessively high, I would expect to see the majority of that phase's wire discolored or burnt instead of just one spot. Maybe the motor winding was especially poor there, or there was a short there.

How does the soldering on the VESC look? Maybe the current sense resistor wasn't soldered properly. If it's signal was missing, the controller might have allowed the current to rise too much and that could be what damaged everything.

Thank you Addy. It seems clearly to be an overcurrent on one phase (including on the VESC).
Has anybody else an idea about this problem ?
I've just ordered another motor (hopping that my controller is still OK) to retry the test !

If you're going to try and use that VESC again, I recommend you use it with a power supply that's not very strong. This way, if there is a problem, there's not as much energy available to damage the motor or VESC. When I was first testing my VESC I hooked it up to my DC bench power supply and I ran it at something like 18V with a current limit of 2A.

Good idea, thanks

Addy said:

How does the soldering on the VESC look? Maybe the current sense resistor wasn't soldered properly. If it's signal was missing, the controller might have allowed the current to rise too much and that could be what damaged everything.

Click to expand...

The soldering looks OK. And what is curious is that I have tested the motor a few days ago without any problems (not on the FOC mode though). Perhaps my VESC has been damaged (I took it in my bag in travel) meanwhile.

You can use an ohmmeter and measure each FET on the controller to see if any of them are shorted. From drain to source (the legs with the heavy copper connections), it should measure like a diode. Measure with the probes in both directions.

From a casual glance, I suspect the winding on that stator tooth as defective. or was damaged.

Q?-has that motor ever run on any other controllers for a period of time?

In an over-current event, I would expect to see more discoloring of all the windings involved.
(that would be the adjacent tooth & the opposing pr. on a DLRK wound motor)

Triple check your controller for shorting....& make yourself a current limiter/smoke stopper. they are always a good idea.

good luck.

Thank you for your advices