Area of Application
Due to small size, high reliability, independence of location and the fact that it is totally maintenance-free, a thermo switch is the ideal instrument for perfect thermal protection.
Function
By means of a resistor, heat is generated by the supply voltage after breaking the contact. This heat prevents any decrease in temperature below the value necessary for the reset temperature TE. In this case, the switch will keep its contact open, irrespective of its ambient temperature. Reset of the switch, and thus closing the circuit, will be possible only after disconnection from the supply voltage.
Thermo switches only react when external thermal heating affects them. The thermal coupling to the source of heat is effected by means of a bimetal disk lying directly below the metallic covering cap.