Reasons for not starting of three-phase asynchronous motor are the following:1, the power is not switched on;2, fuse;3, the stator or rotor winding circuit;4, the stator winding ground fault;5, the stator winding phase short circuit;Error6, stator winding;7, overload or mechanical transmission is jammed;8, the rotor copper bar loosening;No lubricating oil9, bearings, shaft due to thermal expansion, obstruct the rotary in bearings;10, control equipment wiring error or damage;11, the over current

Often the client advisory motor surface temperature, in the absence of accurate measurement conditions, can by hand to sense temperature, now we will share this correspondence is as follows, to facilitate the estimation of temperature.1 detected part temperature at 0 degrees, finger feeling cold, if long time continuous touch, will produce a piercing pain;2 when the detected parts temperature at 10 degrees, feel is cool, but generally can endure. When the detected parts temperature is around 20

1, the drive belt removing, rotary machine spindle is driven by hand, look at the spindle rotation is flexible. If the driven machine damage part or dirty institutions hinder spindle rotate flexibly, namely overload.2, the current meter and power series, running motor, if the meter readings greater than the motor nameplate ratings, that motor overload.

The stator slot size is determined, be sure to put the number of turns of wire in the groove, each turn to several strands of parallel, how much is the share of the gauge. Wire winding of the three-phase induction motor stator is often used to reduce the number of shares and wound, skin effect, of course, and around the number can not be too much, so as not to cause the difficulty on the process. And when the gauge can be the same around the wire gauge, can also be a two gauge adjacent. To pay o

1, the power supply voltage is too high or too low;2, overload;3, operation of single phase motor;4, the stator winding ground fault;5, damage of bearing or bearing too tight;6, stator winding or phase to phase short circuit;7, the ambient temperature is too high;8, the motor is not smooth or fan duct damage.

The common squirrel cage asynchronous motor has many advantages, but its direct larger starting current, the starting torque is not large. Using the method of step-down start to reduce the starting current, but also significantly reduce the starting torque. In order to improve the performance of the starting motor, can begin from the rotor slot, using the skin effect, the rotor resistance increases when starting, in order to increase the starting torque and reduce the starting current, during no

(1) the three-phase power supply voltage unbalance.(2) a motor phase winding part of the coil assembly or wrong.(3) the motor windings are short-circuit. If a short circuit, the motor not only fever, accompanied by a special noise.(4) motor stator winding open circuit.Most of the user the power problems, specific detection method usingphase inversion.Motor, three-phase current unbalance。

(1) the air gap between the stator and rotor exceeds the specified value;(2) the motor rotor axial displacement of rotor end; refers to shrink to the stator core, the flux increases in reluctance ends meet, resulting in the no-load current is too large.(3) ball bearing wear and shaft bending caused by stator, rotor rub. Although the Department at the motor no-load, such as load, so that the no-load current is too large.(4) each phase winding is not enough.

(1) the power supply voltage is too high;(2) the power supply voltage is too low;(3) the voltage unbalance;(4) the three-phase unbalanced power.

(1) the electrical environment temperature is too high, the air inlet temperature is high;(2) into the air with debris blocked, so that the poor into the wind, causing air flow into the small;(3) the internal dust motor too much, the impact of heat;(4) fan is damaged or is reversed, resulting in no wind or small air volume;(5) not installed wind cover or the motor end cover not installed wind deflector, resulting in motor without wind path of;(6) enclosed motor fin defect too, radiating area dec