The common failures of refrigerator compressor starter mainly include: relay wire loose, off, joints wear and tear serious; power on with a buzzing sound; voltage is too high or too low; starter or thermal protector and compressor improperly matched; short circuit of the motor's windings and so on.
Specific explanations are as follows:
1, relay wire loose, off, joints wear serious
Starting relay failure will make the compressor running out of tune, start capacitor can not be cut off from the circuit after the start or the compressor can not be started after the normally closed contact is broken before the boot.
Overload protection relay malfunction, will make the air conditioner can not operate normally, caused by the relay wire loose, off, contact point wear or melt welding, overly dirty, uneven, coil short circuit or disconnection, etc.?
2, boot only a few seconds of startup, and there is a buzzing sound
The use of the start relay compressor, when you hear the compressor has a "buzzing" sound and can not start, you should check the start relay contacts are good. The main fault of the relay is the reset spring plate elasticity is weakened, start contacts closed and difficult to jump open. Starting current adjustment screw can be adjusted, if the adjustment screw is not easy to unscrew, the spring can be used flat pliers outward wrenching, until adjusted to normal.
3, the voltage is too high or too low, and the compressor frequent vibration
When the voltage is too high through the starter current increases accordingly, when the current exceeds the permissible range, the start contact that can not release the start winding and can not be disconnected. In normal circumstances after the motor start 1s start winding should be disconnected, if you can not disconnect, there is a risk of being burned.
4, the starter or thermal protector with the compressor improperly matched
compressor motor starting current than the normal starter release current is too small, will cause the start contact can not be released, the thermal protector will soon jump open, resulting in the compressor can not run normally. For example, the thermal protector heating element capacity is small, even if the temperature gradually rises to the contact jumped open.
5, the motor winding short circuit or compressor internal moving parts have stuck phenomenon, so that the motor work current overload thus making the start relay overload protection contacts repeatedly.
Reference:
Baidu Encyclopedia-Start Relay
Baidu Encyclopedia-Compressor-Common Failures