Parts:
- Turnigy Aerodrive SK3 - 3542-800kv Brushless Outrunner Motor
- CUI - AMT102 encoder
- Custom 3D printed mount for the motor and the encoder
- ODrive 3.2 configured step/dir
- Teensy 3.2 controlling the process
Setup:
Somehow the mounting screw of the encoder mount touched the base of the motor. In my mind it should not be a problem since the base of the motor should not be connected to one of the input leads.
Story:
- At a certain point while the motor was running I saw a spark striking between the case of the encoder and the screw mounting the encoder to the 3D printed mount. Which in his case was touching the motor case/base.
- I turned everything off, remounted the encoder differently, using different mounting holes, who don’t touch the encoder case and don’t touch the case/base of the motor.
- At this point I should have realised that the case/base of the motor should never conduct current.
- Anyway, I repower the ODrive, the calibration sequence seems to work correctly.
- At this point I trigger the Teensy to start the installations initiation process and nothing happens.
- While reaching over the ODrive to push a button connected to the Teensy I noticed that the ODrive is radiating a lot of heat. I immediately turned off the power.
- At that point I notice the smell of the melting PLA motor mount.
Cause of failure
Overheating damaging the insulation of the windings causing a short to the base of the motor, causing a short between ground via the encoder casing.
Side notes
- Teensy survived
- Odrive looks fine as far as I can tell
- It happened during the documentation process of my projects writeup for the ODrive Community
