To eliminate the grounding fault of the motor winding
First, observe the damage of the winding. Except for the insulation that has aged and become brittle, it can be repaired locally.
If the grounding point is at the outlet of the notch or the bottom of the slot coil, and only one wire is damaged, the winding can be heated. After the insulation softens, use a scribing plate to pry open the slot insulation of the grounding point, insert a natural hard mica sheet of appropriate size or a 0.5~1mm thick cloth-grained laminate, and then apply insulating paint and repeat the above method to check until there is no grounding phenomenon.
If the insulation of more than two wires at the grounding point is damaged, the slot insulation and the insulation between the wires should be repaired in the same way. Usually fill in a small piece of yellow wax cloth to separate the two wires and apply insulating paint to avoid inter-turn short circuit faults.
If the grounding point is a coil of a phase winding, the slot insulation must be re-padded or a new coil must be replaced.
Class 1 Div 1 Motor, Coal Mine Motor, Commercial Duty Pump Motor