First, let's take the compressor as an example to talk about the detection of line injuries. A general-purpose turn-to-turn insulation withstand voltage tester, but the detection rate for single-wire injuries is not high. Some motors have 24-slot stators, single-layer and full-distance distribution, and the full slot rate is high.
When assembling the compressor, a large current is applied to the stator to magnetize the rotor magnets. If the stator itself has wire damage, it will easily break during the magnetization process.
The effect of wire damage on the motor depends on the degree of wire damage.
If only a single piece at a different position scratches the patent leather slightly, it will have little effect on the motor without any remedy.
If several pieces are injured at the same position, it will cause inter-turn defects and short circuits. At this time, remedy is needed, such as rubbing glue, etc.
If there is a serious injury to a single thread, especially a bruise, if it is like a quick disconnection at this time, then please scrap it
Because of the high current density at the scar during operation, the motor is prone to damage and failure, causing accidents.
So slight scratches on the patent leather, we can ignore it. Mild line injuries can be remedied, if the damage is severe, don’t continue to use it~
For the coils wound on the stator of asynchronous motors, if the paint on the enameled wire is damaged, it is easy to cause the insulation strength between turns to decrease. If the voltage is too high, it will break down the insulating paint, causing short circuits between turns, and damage the motor in severe cases.
If not only the lacquered surface of the enameled wire is damaged, but also the copper wire is damaged, the cutting area of the damaged enameled wire will be reduced. The large current at full load will easily generate high temperature at this point, which will further increase the resistance of this point, and finally burn the enameled wire. An arc is formed, causing a short circuit.