Editing Cam timer (section)

==Methods used to increase control==
The most basic cam timer rotates continually, which is inconvenient when waiting for events that occur at variable times.

With washing machine cam timers, it is necessary to wait a variable amount of time (for example, waiting for a tank of [[water]] to heat up to a preset temperature). To achieve this, the cam [[electric motor|motor]] is subjected to control by one of its [[switch]]es. The [[timer]] sequence switches the cam motor off, and the motor is started again by the signal from the [[thermostat]] when the required temperature is reached.

Usually, washing machine thermostats have fewer fixed temperature detection points than the number of wash temperatures used. For intermediate temperatures, the cam mechanism uses the stop and wait for the method to heat to the nearest temperature below the one desired, then uses only the fixed timing of the heating element to increase the water to the desired temperature.

Some cam timers also have a fast forward mode, where applying power to a point on the controller causes rapid advance of the mechanism. This is often seen on washing machine controllers. Rapid advance can be achieved by moving of [[Gear train|gearing]], which may be triggered by various means.

Using [[feedback]], external time delay, and other sensory circuits, it is possible to build an electromechanical [[state machine]] using a cam timer. These are common in [[washing machine]]s, where the cam timer runs in phases, but also stops and waits for external signals such as a fill level sensor, or a [[water heating]] temperature sensor.