ODrive v3.6 ARM is burnt

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I test ODrive v3.6-24v with two T-motor 5212-kv340.After rotating motors,the ARM is hot and burnt.
Here are my battery and connection between odrive and motors.

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Looks like you have no brake resistor fitted. This is fine if you are able to pass current back to your battery, but if you are already near the voltage limit then this could cause damage. I would recommend replacing it with the 56V version.

With respect, your wiring is atrocious. Please tidy it up and make sure you have no accidental connection between motor and encoder wiring, including any ground connection on the motor. Ideally use a shielded cable for the motor with the shield connected to the metal of your motor and the negative side of your battery, or else if you don’t have shielded cable, use a fourth power wire (earth) in place of that shield and twist the four motor wires together using an electric drill.
With the amount of induced noise in that tangle of wires, i’m not surprised that something went bang.

What encoder are you using? If it’s the one in the kit from odrive then it includes its own shielded cable with the correct pinout for the odrive, so you don’t need that ratsnest.

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thanks.I’ll have a try ~

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Thank you very much for your help. We still have a few questions:

  1. This is the picture taken when the wires were not completely sorted out. The same connection method has no problem in the separate test. Both damage occurred at the moment of electrification, which could be caused by too much current.
  2. We are using AS5047D. We just noticed that a screw is too long to touch the motor base and connect with the magnetic encoder. Will this make a difference?Can this problem be solved after access to the shielded wire?
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Hi Victor.

  1. Is what I mean by an accidental connection between the motor and encoder wiring.
    Unfortunately this will have allowed a voltage onto the I/O pin of the ARM STM32 controller chip which is higher than it is able to tolerate, resulting in damage to the chip.

If you have a hot air SMD rework station, you may be able to replace the chip at low cost, otherwise you will need a new odrive board.

This is one of the reasons to always ground the motor chassis. If there is any short circuit, it will be to ground potential, and a short to ground is normally survivable to the electronics.

In your case the short circuit current was carried by the encoder wiring, which caused damage to the chip.

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Hi Towen，
Thank you very much!! I think I’ve got it. I will ground all motor shells and replace the wiring of all magnetic encoders. In addition, it seems that my motor wires are too long. Do I need to cut them short?

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Hi Victor,

Yes, you should make your motor wires as short as you can. Not so short that your machine is difficult to service though!
If you can’t make them short, then at least make sure they are kept close together. (ideally, twisted).
If the wires from the same motor are not kept close together, there will be magnetic fields between them which could cause problems. The same goes for your DC power supply wires. Try to keep them running parallel.

Tom

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