Thermocouple is a kind of temperature sensing element, which can also be understood as a primary instrument. For example, we can use thermocouples to measure temperature directly. Or we can think of it as an energy converter, because it can turn heat into electricity.
Generally, two types of conductors are used in the closed circuit. Because of the difference in materials, the electron density produces the corresponding electron diffusion, and the potential is generated after the stability and equilibrium. When there is gradient temperature at both ends, current will be generated in the circuit, which will generate thermoelectric EMF. The greater the temperature difference, the greater the current will be. Therefore, we can use thermocouple to measure the thermoelectric EMF and know its temperature value.
In practical application, the technical advantages of thermocouple are very obvious: firstly, the element has a large temperature measurement range, and its performance is relatively stable; secondly, its measurement accuracy is guaranteed, because it can directly contact with the measured object and is not affected by the intermediate medium; thirdly, its thermal response time is fast, and the response to temperature change is flexible.
Not only that, in the temperature measurement work, from - 40 ℃ to + 1600 ℃, thermocouple can carry out continuous temperature measurement. Its performance is reliable and stable, and has good mechanical strength, long service life, safe and convenient.
However, in the process of temperature measurement, there are certain preconditions. One is that the thermocouple must use two different properties but meet certain requirements of conductor or semiconductor materials to form the loop, and the other condition is that there must be a temperature difference between the measuring end and the reference end.
The above is mainly to introduce the technical advantages of thermocouple and temperature measurement conditions. I believe that after understanding these contents, we have a deeper understanding of thermocouple.
On 2018-08-08 11:45:46
