Asynchronous motor common faults of examination and ruled out

In the operation of the asynchronous motor in due to friction, vibration, insulation aging, hard to avoid failure.If these faults timely inspection, found and ruled out, can effectively prevent the happening of the accident.A, the asynchronous motor fault inspection 1.Listen to the voice, carefully to find fault point of ac asynchronous motor in operation, if found a finer "buzzing" sound, no change of high and low, is acmotor2.blogspot.com a normal voice, if the voice thick, and a sharp "buzzing", "hissing" sound is the forerunner of faulty, should consider the following reasons: (l) loose core motor vibration in the operation, the change of the high and low temperature, can make the iron core deformation of the retaining bolt, silicon steel sheet caused by loose, produce large electromagnetic noise.(2) the voice of the rotor spinning rotor noise, produced by the cooling fan, is a kind of "whoops" sound.Like drums of the "product" sound, this is the motor in sudden start, stop, reverse connect braking variable such as cases, the accelerating torque rotor iron core and the shaft with the loose, light person can continue to use, the person that weigh apart to check and repair.(3) in the operation of the motor bearing noise in, must pay attention to bearing the change of the voice, one end of the screwdriver to touch on the bearing cover, the other end on the ear, can hear the sound of the motor internal changes, different area, different fault, has a different voice.Such as crunching sound is produced by the irregular motion of the roll bearing inner gun, it related to the bearing clearance, grease state."Hissing" sound is metal, usually caused by bearing the lack of oil, add grease agent should open bearings.

2.The use of the sense of smell, failure analysis and motor is no peculiar smell in the normal operation, if the sensed the ignorance, is the fault signal, such as, anxious burnt flavour is insulation barbecue, and with the temperature increasing of motor, serious when Motor vehicle still can smoke; Such as oil coke, mostly lack of oil bearing, in dry grinding state near the end of the oil and gas evaporation of peculiar smell.3.Using the handle, check failure Touch the shell, can be broadly determine high and low temperature rise, if a touch the motor shell with the hand feel is very hot, the temperature is very high, should check the reason, such as: heavy load, the high voltage, and then for troubleshooting.Second, the common faults 1.The motor did not start torque, or won't start when there is no load and abnormal sound.Reason: (l) three-phase power circuit (including) the stator winding of knife switch, fuse one phase power, caused by single phase started.(2) the power supply voltage is too low.(3) bearing excessive wear, close to the one side of the stator and rotor caused by different heart of stator and rotor, air gap is not rotor balancing machine uniform.2.The motor starting torque is small, can't start, when the load, load increases when the motor stalling, sometimes send strong noise, local heating.Reason: low voltage grid and winding interturn short circuit, break or desoldering phenomenon in the rotor winding, start-up phase after a break caused by single phase operation.3.The starting current is big, and don't balance, noise big, cause protective device and cut off power supply.Reason: the stator winding wiring method may not be correct, winding of insulation aging.