Generally speaking, the casing is charged, the control circuit is out of control, and the winding is short-circuited to generate heat, which makes the motor unable to operate normally. So how should we check the problem?
Observation:
Observe whether the insulation at the end of the winding and the wire slot is damaged or scorched, if so, it is the grounding point.
Multimeter inspection method:
Use a multimeter to check the low resistance gear, if the reading is very small, it is grounded.
Megger method:
According to different grades, choose different megohmmeters to measure the insulation resistance of each group of resistors. If the reading is zero, it means the winding is grounded. However, if the motor insulation is damp or breached by accident, it needs to be judged by experience. Generally speaking, when the pointer swings at "0", it can be considered that it has a certain resistance value.
Lamp test method:
If the test light comes on, the winding is grounded. If sparks or smoke are found somewhere, it is the winding ground fault point. If the light comes on even slightly, the insulation is broken down by ground. If the light does not come on, but there is also a spark when the test rod is grounded, it means that the winding is not broken, but it is badly damp. Hardwoods can also be used to strike the lip of the casing. When tapped somewhere, it shows that the current breaks from time to time, and that's the ground.
DC Motor Repair Manufacturers
Current wear method:
Use a voltage regulating transformer. After connecting the power supply, the grounding point heats up rapidly, and the place where the insulation smoke is the grounding point. Special attention should be paid to the fact that the small motor should not exceed twice the rated current, and the time should not exceed half a minute; the large motor should be 20%-50% of the rated current or gradually increase the current, and cut off the power immediately when the ground point just smokes.
Group elimination method:
For the grounding point in the iron core, the burning is serious, and the burning copper wire is fused with the iron core. The method used is to divide a grounded phase winding into two halves, and so on, and then find the grounding point.
