Maintenance method of three-phase asynchronous motor
For three-phase asynchronous motor with continuous operation, daily maintenance contents include: appearance inspection, whether the fan works normally, whether there is abnormal vibration, whether the coupling connection is reliable, whether the base is fixed firmly, whether the bearing works normally (listen to the sound), whether the temperature is normal (infrared thermometer), regular inspection of wire connectors and switch contacts, and whether the working current is normal (clamp type ammeter), In addition, the carbon brush and slip ring must be checked for the wound motor.
Measuring end
(1) First identify the two ends of each three-phase winding. Adjust the multimeter to the resistance gear for measurement. All coils of the same phase are connected without resistance value, and all coils of the same phase are not connected. Therefore, according to the multimeter, it can be distinguished that the two ends belong to the same phase winding outgoing line.
(2) Distinguish the same-name ends of the outgoing wires of the coils on both sides, adjust the pointer multimeter to the DC current range with the minimum range, connect the two wire ends of the winding of any phase to the meter, and then touch the positive and negative poles of the dry battery instantaneously together with the two wire ends of the winding of the other phase. At the moment when the dry battery is connected to the coil, if the meter needle swings to the side greater than zero (that is, clockwise swing), The positive pole of the battery and the black probe of the multimeter are the same end, and the reverse is true.
Source: excerpts from Baidu Encyclopedia
