The use of motor is more, general machinery, home appliances are installed; Like textile, metallurgy, aerospace, machinery manufacturing, chemical industry, etc., are inseparable from the motor; Most of the power in factories is driven by electric motors. In daily life, water pump, electric fan, car starting, electric car, construction land mixer, crane and so on all need to use the motor.
Motor is a kind of mechanical equipment, in the process of running due to friction, vibration, insulation aging and other reasons, it is hard to avoid failure. If these faults are checked, discovered and eliminated in time, accidents can be effectively prevented.
Common faults:
1, the motor has no starting torque, or can not start when no load, and gives out abnormal sound.
The reason:
(1) Three-phase power supply circuit (including knife switch, lead stator winding) has a phase outage, resulting in single-phase start.
(2) The power supply voltage is too low.
(3) Excessive bearing wear makes the rotor close to the side of the stator, resulting in different centers between the stator and the rotor, and uneven air gap.
2, the motor starting torque is small, can not start when there is load, load increases when the motor stops, sometimes a strong noise, local heating.
Cause: low voltage of power grid, short circuit between turns of winding, disconnection or diswelding phenomenon in rotor winding, one-phase disconnection after starting, resulting in single-phase operation.
3, the start current is large, and unbalanced, loud, resulting in the action of the protection device and cut off the power supply.
Cause: The connection method of the stator winding may be incorrect, and the insulation of the winding to the ground is aging.
If the motor damage is equal to a machine can not operate, the motor is the backbone of the equipment, good maintenance of the motor, in order to keep the equipment running.