ADD:No.789,liming South Road,RongCheng City,Shandong Province,China.
Handling of winding faults
Winding is part of motor. Aging, wetting, heating, erosion, foreign matter intrusion and external force impact will cause damage to windings. Motor overload, undervoltage, overvoltage and phase running can also cause winding faults. Windings fault is usually divided into winding grounding, short circuit, open circuit and connection error. Now the fault phenomenon, the cause and the inspection method are explained separately.
The grounding caused by the damage of the winding and the insulation of the core or the casing.
1. Failure phenomenon
The electric housing is charged, the control line is out of control, and the winding is short circuited by heating, which causes the motor to be unable to operate normally.
2. Cause the cause
Winding insulation resistance decreased damp motor; long-term overload operation; harmful gas corrosion; metal xenembole winding internal insulation damage; damage to touch the core insulation of stator winding coil; the winding end touch base cover the stator and rotor friction caused by insulation; burn; lead wire insulation damage and shell together; over voltage (such as lightning). Insulation breakdown.
3. inspection method
The observation method. Through the visual winding ends and the line slot insulation for any damage and observe the blackened traces, if it is to take place.
The multimeter test. Use the multimeter low resistance gear check, the reading is very small, it is ground.
The megohmmeter method. According to the different levels of insulation resistance with different zhaooubiao measureeach group resistance, if reading is zero, said the windinggrounding, but to motor insulation damp or by accident and breakdown, to judge on the basis of experience, generally speaking pointer in the 0 place withoutswaying timing can think it has certain the resistance value.
The lamp test method. If the test light is on, the windings are grounded, and if a spark or smoke is found somewhere, it is the grounding fault point of the windings. If the lamp is light, the insulation is grounded. If the lamp is not bright, but the test rod is connected to the ground, the spark also appears, indicating that the windings have not been penetrated, but are seriously dampened. Also available in the mouth of the hardwood shell tapping edge knock to a place, a light one out, that current when the broken, then it is take place.
The current wear method. With a voltage regulating transformer, after the power supply, the place is quickly heated, the insulation is the place where the smoke is the place. Special attention should be paid to the fact that a small motor must not exceed two times the rated current, and the time does not exceed half a minute. The large motor is rated at 20%-50% of current, or gradually increases the current, and the power is cut off immediately when the location is just smoked.
Such as packet elimination method. The burning of the burned copper wire is fused with the iron core for the place in the core and the burning of the core. The method used is to divide a phase winding of the ground into two halves, and by analogy, to find the connection place at the end.
In addition, there are high pressure test method, magnetic exploration method, vibration method and so on, here is not introduced one by one.
4. treatment method
The ground should be drying caused by damp winding, when cooled to 60 - 70 degrees Celsius, insulating paint poured after drying.
At the end of the winding insulation damage, on the ground to be insulated, painting, drying.
The windings to place in the slot should be rewound, winding or replace part of the winding element.
Finally, different megabytes are used to measure and meet the technical requirements.