Why would my Motor Spark and smoke my ESC

Something came to mind as I was flying just a little bit ago… Have you checked your current draw per ESC in the telemetry data?

On my X6 I only average a few amps per motor, far far below the 65A max draw of the Tekkos

I will try this when I get it all put back together on the bench. I am going to rebuild the way that you suggested and then test. Should have it done sometime next week (waiting on ESCs and wire…). I will keep you posted.

Side note - when I was doing some bench test and look at the current. Was normally very low; but, if I threw that Throttle all the way up - I would see some spikes at 100+ amps.

Even 100 amps ÷ 6 motors is about 16ish amps per esc

Could you make some closeup photos of the burnt ESC’s (with some good light) and also a closeup of one or two working ones ?

So it looks like that all of them had the same failure, a ceramic cap, close to the FETs went short.
It should be a wrong series of capacitors, or some flux, solder residual that were not cleaned out. I don’t think that it is caused by flex, since the PCB is quite thick and the capacitor is located near the center.

Also have to notice that the soldering job on the cables are terribel, not enough heat and not enough flux, most of them looks like a terrible cold joint to me.

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Just a question from looking at the pics.
The 3 control wires are marked GND - TLM - PWM and you have the red wire connected to TLM.
How do you have the other end connected to the PH?

Hi did you manage to sort out the issue? Are your esc’s opto or with ubec? Try to make them opto only if you can, so only connect the negative and signal wire to pixhawk or receiver, my esc got hot to the point I couldn’t touch it within seconds, I was testing a motor so I powered the reciever with external 5v and soon as I connected the 5v ubec from esc to the reciever it started over heating immediately. So just power pixhawk servo rail with a dedicated 5v ubec and make all your servos opto only. Hope this helps

What is the All Up Weight (AUW) of the Hexacopter ??
I think the ESC what you selected is under rated.
What is the battery voltage??

I only have 2 wires going to the FC. Negative and signal. Nothing to power.

Black is connected to -. PWM is connected to Signal. TLM is connect to the Telemtry port on the TELEM2 slot.

AUW is About 7Kg. The battery is 6S. 25V

1.ESC is rated for 60A and 6S. Then no problem in selection.
Heat sink is recommended for this ESC.??..I don’t think it is not thermal failure.

2.I think this is happened because of Short circuit/Over current on motor side.

3.Check resistance between R and Y ,Y and B, B and R, Terminals should be nearly Equal of motor side.

If the same thing happened for all 6 ESC’s. There is chance of problem with firmware of ESC.

you are powering telemetry using this port??
Usually ESC don’t require any Telemetry signals

… BLHeli32 esc’s has serial telemetry, this is why he connects it to the telemetry port. …

Yes got it…We can receive Voltage, Current and Speed data from this TLM pin.

Ok - Drone is back together… Telemetry is working great - except I have a ghost showing up on ESC #8

How do these ESC setting look for this setup…


Hexacopter
Frame. Tarot X6
FC Pixhawk 2.1 Cube - Orange
ESC BLHeli 32 DSHOT150
Motors U7 420kv
Battery: Tattu 17000mAh 22.8V 6s 15C Lipo Battery

Looks good to me. Do you mean a ghost on the mission planner logs?

the answer - upgrade to the manufactured recommended ESCs. I have the T-Motor Flame 80A ESC - problem is gone.

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