When the internal temperature of the refrigerator rises to a certain temperature, the electrical contacts of the temperature controller are turned on. 220V mains electricity passes through the compressor motor and the running winding through the contacts, heating wires, overload protection contacts and solenoid coils. Form a loop. At the moment the circuit is connected, the motor has not started yet, and the loop current is very large, and the electromagnet attracts the armature and turns on the starting contact. After the current passes through the start winding to start the motor to make the motor rotate, the current in the running burning group is reduced, the armature rebounds, the start contact is disconnected, the motor is maintained by the running winding, and the refrigerator starts to cool. When the refrigerator cools to the top set value, the electrical contact of the thermostat is disconnected and the motor stops. After that, after the temperature of the refrigerator rises, it will continue to work in cycles according to the above process.
The overload protection contact in the relay protects the motor. When the motor fails and the current exceeds the rated value, the heating wire causes the bimetallic sheet to be heated and bent. Attracted by the permanent magnet, the moving contact and the static contact are quickly separated, cutting off the running path of the burning group. After the bimetal electric cooling is reset, the motor restarts.
