Is a kind of temperature sensing element, is a kind of an instrument, thermocouple temperature measurement directly. Composed of two different composition material of the conductor closed loop, because material is different, different electron diffusion of electron density, stable equilibrium is produced after electric potential. When temperature gradient is at both ends, the loop will be current, produce thermoelectric emfs, the bigger the temperature difference, the greater the current will be. To know the temperature after the measured thermoelectric emfs. Thermocouple is, in fact, a kind of energy converter, can convert heat into electricity.
Thermocouple technical advantages: wide thermocouple temperature measurement range and stable performance compare; High measurement accuracy, thermocouple direct contact with the object being measured, not affected by the intermediate medium; Thermal response time is fast, flexible thermocouple response to temperature changes; Wide measurement range, thermocouple from 40 ~ + 1600 ℃ can be continuous temperature measurement; Thermocouple performance is stable, good mechanical strength. Long use life, device for lunch.
Galvanic couple must be composed of two different nature but fit certain requirements of the conductor or semiconductor materials constitute a loop. Thermocouple measurement must have a temperature difference between side and reference.
The two different information conductor or semiconductor welding, A and B constitute A closed loop. When the conductor A and B two persistent point temperature difference between 1 and 2, occurs between the electromotive force, therefore constitute the size of A current in the circuit, this kind of phenomenon called the thermoelectric effect. Thermocouple is using this effect to work.