The troubleshooting of motors in common compressors involves many aspects. Here are some troubleshooting methods:

1.Winding break inspection: Use a megohmmeter, multimeter or check lamp in series to check the end point and neutral line of the running winding. If the meter is not conducting or the lamp is not bright, it indicates that the winding is broken.

2.Winding short circuit check: Use a megohmmeter or multimeter to check the insulation between any two phase windings. If the insulation resistance is very low, it means there is a short circuit between the windings.

3.Winding leakage inspection: The motor winding is damp, the insulation is aged, or the motor winding contacts the housing due to transportation or moving, which damages the insulation of the enameled wire, which may cause leakage faults. Wet motors with reduced insulation performance should be dried. For sealed motors, the whole machine can be placed in a box and baked at 110°C for 6 to 8 hours.

4.The method of rewinding the motor winding is as follows: after confirming the motor failure, remove the entire winding and record the wire diameter and original number of turns before disassembly. Remake the winding and measure its resistance value, embed each winding into the fixed slot in the original direction, tighten the winding with cotton rope, assemble the rotor, and after power-on test, put the motor into a drying oven at 100℃ for 4 to 6 hours after normal start-up before it can be put into use.

5.Common fault analysis and repair: For example, if the start relay is continuously overloaded, the contacts of the overload protector are disconnected, and the compressor does not rotate, it may indicate that the compressor motor start winding is faulty due to a short circuit. If the compressor does not rotate after power is turned on, and the resistance of the running and starting windings is infinite, the possible reason is that the wiring of the motor winding is disconnected or the lead wires in the motor and the casing are loose, causing the motor to be short-circuited.

6.The compressor motor barely starts and runs. Failure: the running current is more than double the normal value, the noise is significantly increased, and the overload protector is disconnected, which may indicate a short circuit between the motor running windings.

7.Compressor leakage fault: The resistance between the common point of the casing terminal and the casing is zero, indicating that the common point is short-circuited to the ground.

8.After the refrigerator is running, the fuse blows continuously: the motor is running or the starting winding is short-circuited to the casing. The normal value should be above 5MΩ.

Through these maintenance methods, common faults of compressor motors can be effectively identified and resolved to ensure the normal operation and service life of the equipment.