Quick and Easy Tutorial on how to Diagnose and Repair your Brushless DC Motor
The simple brushless DC hub motor. It is the one thing that revolutionized the whole concept of Personal Electric Vehicles (PEVs).
Never before has a propulsion device been placed into such a small package consisting of only 3 main components that are low maintenance and easy to use:
- Stator with permanent magnets
- Electromagnet rotor with bearings
- Hall sensor controller board
The rest of the components are just wires and hub covers.
We will not go into too much detail as this is the DIY tutorial but as you can see the graphic above, due to the simplicity of the design, there are only a few components that can be worn out or damaged:
- Bearings. The motor bearings can be considered worn out once you feel that they do not roll as smoothly as before or if they just completely collapse, it can cause the motor is get jammed. The bearings can typically last for at least the first 5000km of the e-scooter’s life.
- Faulty controller board or sensors. For some motors without hall sensors, there are only 3 motor wires running from the motor controller out of the motor. Those are the simplest type so if there are any issues, the problem should be just with the wires. The wires by itself does not get damaged but due to accidents, they could be damaged externally. The control board rarely get damaged unless water enters the motor as it is a passive circuit.
- For motors with the hall sensors that feedback into the ESC (controller of the e-scooter), the the wires are more complicated. There are the 3 motor wires and the 5 or 6 hall effect sensor wires. The graphic below shows the 3 hall effect sensors with the (blue) control board. Like before, the control board will not really get damaged. However, the sensors do due to water, heat, vibration or poor quality.
Really. Thats it. You either fix the bearings, wires or sensors.
Heres Part 1 on how to fix the wires of the ZERO 9 motor which is a standard 500W/600W brushless DC motor:
If your electric motor is a split hub with screws on both sides, you can remove the stator from the magnetic rotor easily as shown in this video:
However, if your hub motor is NOT a split hub, you have to use this method to separate the stator from the electric rotor:
Part 2 will be on how to replace the Hall sensors so stay tuned…