Trafag thermostats function according to the liquid-filled capillary tube principle. On a change of temperature at the temperature sensor, the capillary filling expands and actuates a bellows. In turn a high-precision mechanism triggers a micro switch. Through the on/off signal of the micro switch, it is possible to control an instrument or a process controller. Thermostats function independently and without need for electric power.
All thermostats with remote temperature sensors are so designed that no measurement error occurs if the bellows system with the switching device is exposed to fluctuating ambient temperatures. This means that other than in the case of non-compensated capillary sensor thermostats, switching accuracy is preserved even at extreme ambient temperatures. A fully modular manufacturing concept enables the assembly of a large number of customer-specific devices.
In the event of failure of the sensor (e.g. breakage of the sensor), the thermostat actuates the micro switch and can also indicate a disruption. Available as an option.