ELECTRICAL OPERATION. - Let's look at the electrical operation of a washer. With the plug connected to the outlet, the timer is turned to WASH and the dial is pushed in or pulled out, depending on the type of switch. The operational cycle continues as follows:
1. From the ON/OFF switch, power flows through the temperature control switch and the water-level switch to the inlet solenoid valve. That energizes the inlet valve, allowing the tub to fill.
2. The timer motor is de-energized during the fill cycle because of the open set of contacts in the water- level control switch.
3. Once the water reaches the proper level, one set of contacts opens to shut off the fill solenoid. The other contacts close, sending power to the timer and, at the same time, energizing the motor for the wash cycle.
4. At the end of the wash cycle, power is fed from the timer to the solenoid on the pump, engaging the pump and removing water from the tub.
5. Once the tub is empty, the solenoid for the spin cycle is energized. Its power is fed through the door switch to the solenoid so that, if the door is opened, the machine shuts down
6. During the spin cycle, the water pump is running, and the tub is operating at high speed The timer has provided a bypass circuit around the now open set of contacts in the water-level control switch
7. Once the cycle is completed, the pump, the high-speed solenoid, and the motor are de-energized because there is no water in the tub.
8. The water-level switch closes, energizing the inlet water solenoid to fill the tub for the rinse cycle.
Figure 7-3. - Typical wiring diagram of a washing machine. 7-4Continue Reading