Most appliance manufacturers have now found it advantageous to employ a small switch or micro-switch, to stop the spin action. An actuator protruding from the lid of the automatic washer causes the switch to open before the lid is raised 2 inches. Electrical, either type of spin-stop lid or door safety switch is usually connected to wires between the spin solenoid and the timer. In this way, when the operator raises the lid during spin, the switch opens and the timer circuit to the spin solenoid is broken. By keeping the actuator clean and free of debris, you can avoid unwanted appliance repair service calls.
Controlling an electric water pump, to keep a container full of water. Just as in a washing machine, the depth of the water can be sensed from a hose connected to the base of the container.The advantage over a float switch is that the level is easily adjustable. Providing a low water level warning eg, the switch could be used to activate a buzzer or light if the liquid level in a tank drops below an adjustable point.