Common faults and solutions for motor maintenance of gearbox

Common faults and solutions for motor maintenance of gearbox

During the use of the motor, it is more or less possible to experience malfunctions due to various issues, such as overloading the motor during operation, resulting in overheating or incorrect wiring of the motor!

1. After the timing is turned on, the motor cannot start, but there is a buzzing sound

Possible reasons:

(1) Not all power supplies have been connected for single-phase starting;

(2) Motor overload;

(3) Stuck by dragging machinery;

(4) Open circuit or broken wire in the rotor circuit of a wound motor;

(5) The first end of the stator is connected incorrectly, or there is a wire break or short circuit.

Handling method:

(1) Check the power lines, motor leads, fuses, and each pair of contacts of the switch, identify the open circuit position, and eliminate it;

(2) Start with no load or half load after unloading;

(3) Check the dragged machinery and troubleshoot it;

(4) Check the engagement of various contactors such as brushes, slip rings, and starting resistors;

(5) Reassess the beginning and end of the three-phase winding and check for any loose wires or short circuits.

2. It is difficult to start the motor, and after adding the rated load, the speed is relatively low.

Possible reasons:

(1) Low power supply voltage;

(2) The original angle connection was mistakenly connected to a star connection;

(3) The cage end of the squirrel cage rotor is soldered off, loose or broken.

Handling method:

(1) Increase voltage;

(2) Check the wiring method of the nameplate and correct the wiring method of the stator winding;

(3) After examination and symptomatic treatment.

3. After starting the motor, it generates heat exceeding the temperature rise standard or emits smoke

Possible reasons:

(1) The power supply voltage is too low, causing excessive temperature rise of the motor under rated load;

(2) Poor ventilation of the motor or high environmental humidity;

(3) Motor overload or single-phase operation;

(4) The motor starts frequently or has too many positive and negative rotations;

(5) The stator and rotor rub against each other.

Handling method:

(1) Measure no-load and load voltage;

(2) Check the motor fan and clean the ventilation duct, strengthen ventilation to reduce ambient temperature;

(3) Check the current of each phase with a clamp type ammeter and treat it accordingly;

(4) Reduce the frequency of forward and reverse rotation of the motor, or replace the motor that is suitable for frequent starting and forward and reverse rotation;

(5) Treatment of aunt's symptoms after examination.

4. Low insulation resistance

Possible reasons:

(1) The winding is damp or water drips into the interior of the motor;

(2) Dust and oil on the winding;

(3) Aging of stator winding insulation.

Handling method:

(1) Heat and dry the stator and rotor windings;

(2) Wipe the end of the winding with gasoline and dry it;

(3) Check and restore the insulation of the outgoing line or replace the insulation wire board of the junction box;

(4) Generally, all windings need to be replaced.

5. The motor casing is live:

Possible reasons:

(1) Insulation or terminal box insulation wire board for motor leads;

(2) The end of the winding collides with the casing;

(3) The motor casing is not reliably grounded

Handling method:

(1) Restore the insulation of the motor leads or replace the insulation board of the junction box;

(2) If removed