Coil quality problems: winding, winding and end forming of the coil are not good, or winding quality is not good, such as insufficient copper wire, loose insulated wire, or uneven winding thickness, which leads to coil turn looseness and easy to cause turn-to-turn short circuit.
Bad forming of coil end: The coil end is not well formed and uneven, and vibrates during operation, resulting in turn-to-turn short circuit.
Bad winding of coil: Bad winding of coil leads to uneven coil end and vibration during operation, which leads to turn-to-turn short circuit.
Too tight end shaping: too tight end shaping leads to excessive inter-turn pressure, inter-turn insulation damage and inter-turn short circuit.
Improper operation: Improper operation can also cause turn-to-turn short circuit, such as wiring error, loose wiring and poor terminal connection.