Thermal Fuse_Thermal Link
The thermal fuse (thermal cutoff) reacts to the acute temperature change, usually heating, in a circuit. Electrical circuits generate heat when the current passes through. In most cases, the heat does not accumulate to a level high enough to affect the circuit. However, it does come at a risk that the circuit and even the entire system burn down when the temperature is too high. This is why most electrical appliances and electronics need a thermal fuse to prevent such a scenario from taking place.
Conventional thermal fuses 'fuse' at a preset temperature to prevent overheating. Other types of thermal fuses, such as thermal switches or thermal cutouts, do not fuse. Instead, they use bimetal materials to react to heat and open or close the circuit according to the temperature change.