Why would my Motor Spark and smoke my ESC

ArduCopter
22

It seems that ceramic capacitor explodes. It is very likely a bad series. Ceramic capacitors are shorts when they cracked.
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23

They are popping after flying a bit. I have not gone very high because I keep popping these. The last one popped (saw an arc on the motor and ESC) but kept working…

24

Well, that underpin the bad series theory, they crack because the vibration.

25

Or if the board is flexed. We (company I work for) actually provide instrumentation services for PCB strain and it’s almost always for ceramic surface mount cap faulures or as an audit tool for various PCB build process’s.

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26

Can we go back to… “How exactly are these mounted?” That would really help to understand if there is board flex or not

27

They are mounted using double faced tape on the frame (not under the motors)

28

Would it help if I mounted these closer to the motor. One of the vendors I was working with said it would be better to have the power cables coming from the motors be the long cable run.

29

You can bring the ESCs under the motors by extending the power wires. However if you do that, you need to keep the caps at the ESCs. Depending on your wire length, you might want to up the capacitor size. I run 1000Uf Ultra low esr caps to help protect the ESCs

30

OK - I will buy some of those. Shouldn’t I see some sort of damage on the capacitors that I currently have on the ESCs when the ESCs are blown out? The ones that came standard with my ESCs are 35v 330uf YXJ.

31

Not necessarily. However the 330s that you have are probably fine. I just like to overdo it when I extend the wires over 12inches

32

Something is definitely not fine. I have smoke at least 4 ESCs.
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33

I agree with you. I have almost 2 dozen of those same ESCs and zero issues.

What power distribution system are you using?

34

The Tarot T6 hub with the COAX cables that came with it.

35

The Tarot T6 hub with the COAX cables that came with it. I have the option to use XT60 connectors. There are 3 XT60 access points.

36

On my Tarot X8 I use the same hub, and again no issues at all

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37

Interesting: I just found this on FOXTECH as a recommendation for the Motors I am using: Motor:U7 KV420
ESC:T-MOTOR T80A (We recommended the T80A ESC as the default combination with U7 @ 6S.)

38

Those motors draw less that the limit of the Tekko’s
Max Continuous current(A)180S…40A

Here is the steps I would take

  1. Get a higher wattage Soldering Iron and clean up all your solder joints
  2. Move the ESCs to under the arms and do not double stick tape them to the arms (allow them to float)
  3. Install higher UF caps at the ESCs
  4. Use only the heatshrink tubing that comes with the Tekko’s
39

This is how my ESCs are mounted on my Tarot X8 and my Tarot X6

The feed wires and motor wires keep the ESCs in place, no double stick tape needed

And here are the Caps

40

Dave, sorry to say that, but this is the best way to break your wires. The wire must be fixed, otherwise it will fatigue and break where the solder end in the wire.

41

Normally I would 100% agree with you, but these ESCs are so super lightweight they have no vibration. I have contemplated a foam backer but in over 2 years I have had zero issues with solder joints

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