When the end of the coil is small, the linear resistance of the winding decreases and the motor power increases slightly. However, it is difficult to embed the wire, and the round hole of the winding is too small. Pushing the rotor during installation may damage the coil paint.

The end of the coil is large, the winding resistance is large, and the motor power is slightly reduced, but it is easy to embed wires. It is also easy to cause short circuit or leakage when the coil end touches the motor end cover.