Troubleshooting of Refrigerator Compressor Buzzing Not Starting
Issuing time:2019-08-24 00:00
Analysis and Maintenance: The reason for judging that compressor has "buzz" sound and does not start is usually the fault of starting relay. Because the refrigerator uses a single-phase asynchronous AC motor, which has start windings and running windings. The phase difference is 90 degrees. The refrigerator starters produced before the 1980s mostly adopt the heavy hammer type.
The working process is as follows: when the refrigerator starts, the starting current passes through the contacts of the starter to start the winding, and the other passes through the wire group of the starter to the running winding. Two routes work in parallel. When the motor reaches 70% to 80% of the synchronous speed, the starting winding will be automatically detached, and the starter will be damaged by overheating for a long time.
In repairing, the faults of adjusting the starter damage are quite common, because the PTC resistance has the advantages of simple structure, no contact, seven arcs and so on. Many repairmen use PTC resistors for direct substitution. In most cases, direct substitution is successful. Pitch up may also cause compressor damage failure V, so here's to remind you.
Theoretical analysis shows that after replacing the starter with PTC resistance, the series resistance of the starter winding can be started. At this time, the current in the starting winding of the current spoon in the running winding has a certain phase difference, so the resulting torque. The value is small. It is only used in the occasion where it is easier to start. If the PTC is used instead of the heavy hammer starter. In order to reduce the impedance value of the starter, it is necessary to remove the starter coils in series in the PTC starter winding loop.
It can be seen from the experimental characteristics of ptc. The current attenuation time in the starting winding is only about 1.5 seconds, such as the starting torque produced by the series resistance of the starting winding is small. It will inevitably lead to the increase of start-up time. If the start-up time does not match the decay time of PTC current, the start-up current of 4-7 times will be borne by the long-distance winding, which should be treated with caution. Therefore. Whether the PTC resistance can replace the heavy hammer starter or not is restricted by the selection of PTC and the condition of refrigerator itself, temperature environment, heat dissipation capacity and so on. It should be treated according to the specific conditions, and should not be replaced forcibly, so as to avoid the bad consequence of burning compressor.