Thermocouple

Devices that measure temperature. Thermocouples consist of two wires of different metals welded together at each end. Each type is classified by its alloy combination. Since electrons in metals carry both heat and electricity, thermocouple voltage is a side effect of heat flow. Each material used as wires (thermoelements) of a thermocouple has a different emf response to a temperature gradient. Due to the Seebeck effect, where a temperature difference exists, there is also a charge imbalance. From this phenomenon, a voltage is generated, and the difference between the two emfs in each wire results in the measured emf of the thermocouple.