Two necessary conditions for thermocouple temperature measurement

Everyone knows that thermocouples are a commonly used measuring instrument with a wide range of applications. There are two prerequisites for thermocouple temperature measurement, which are crucial for thermocouple temperature measurement. Let me introduce the two prerequisites for thermocouple temperature measurement.

Thermocouple is a temperature sensing element and a primary instrument that directly measures temperature. A closed circuit composed of conductors made of two different identity materials, due to the difference in materials, causes the electron density to disperse and stabilize, resulting in an electric potential. When there is a gradient temperature at both ends, there will be current in the circuit, generating thermoelectric potential. The larger the temperature difference, the greater the current. After measuring the thermoelectric potential, the temperature value can be determined. Thermocouples are actually energy converters that convert thermal energy into electrical energy.

The advantages of thermocouple techniques: Thermocouples have a wide temperature measurement range and relatively stable functions; High measurement accuracy, thermocouple directly interacts with the tested tool without being affected by the surrounding medium; Hot response time is fast, and thermocouples have flexible responses to temperature changes; The measurement range is large, and thermocouples can continuously measure temperature from -40~+1600 ℃; Thermocouples have sturdy functions and good machine strength. Long application lifespan and easy installation.

A thermocouple must be formed by two conductor (or semiconductor) materials with different properties but meeting certain requirements to form a circuit. There must be a temperature difference between the measuring end and the reference end of the thermocouple.

Weld the conductors or semiconductors A and B of two different materials together to form a closed circuit. When there is a temperature difference between the two attachment points 1 and 2 of conductors A and B, an electromotive force occurs between the two, resulting in a large or small current in the circuit. This phenomenon is called thermoelectric effect. Thermocouples utilize this effect to perform their tasks.