Type ETR thermostats are meant for use in heating applications such as the temperature control of heating elements in gas heaters, electro-static precipitators, etc.
ETR thermostats are manufactured to perform in high temperature ambience prevailing in industrial atmosphere.
The power element assembly that actuates the switching mechanism is a sealed thermal system comprised of a bellows (power element) and a temperature sensing bulb and capillary tube. The power element system is filled with a liquid / vapour charge selected for the specific application.
Variations in temperature at the bulb (sensing element), cause changes in the pressure within the power element, which in turn actuate the switching mechanism to open or close the desired electrical circuit.
Potential free changeover contacts rated for 16 Amp, 250 V AC are provided for switching and control purpose.
A graduated scale allows the user to set the actuating temperature correctly. The on-off differential (Dead band) is a fixed minimum value and is essentially constant so that the cut-in value follows the cut-out value within the dead band.
