The temperature sensor consists of probe, capillary tube, diaphragm and expansion medium. When the sensor is heated, the medium heats up and expands. The expansion of the medium increases the pressure in the closed-circuit system. The pressure increase is converted into a displacement in the diaphragm.
This displacement, also called travel, actuates a snap-action switch which opens or closes the contacts in the electric circuit. The reference variable is set via the thermostat´s adjusting spindle.
The thermostats operate with very short travel increments. An increment of 0.01 mm in baking is equivalent to a temperature of approximately 3 K. This accuracy is backed by meticulous precision work at the manufacturing stage.
