Thermocouples are temperature sensing components that can directly measure temperature. Their closed circuit is composed of two different materials. Due to the different materials, the density of electrons will be different, and different electron densities will cause electron diffusion. After reaching a stable equilibrium, an electric potential will be generated. When there is a temperature gradient at both ends, a current and thermoelectric potential will be generated in the circuit. The larger the temperature difference, the greater the current. After measuring the thermoelectric potential, the temperature value can be determined. Thermocouples are actually converters that convert thermal energy into electrical energy.

Thermocouples have a wide temperature measurement range, high measurement accuracy, and stable performance. They are not affected by the intermediate medium when in contact with the measured object, and have a fast thermal response time. They are very flexible in responding to temperature changes and can continuously measure temperature from -40~+1600 ℃. The device is simple, strong, and has a long service life.

A Brief Analysis of the Characteristics and Advantages of Various Scale Numbers in Thermocouples

I believe everyone knows that the division marks of thermocouples can be classified into several types, including precious metal thermocouples and low-cost metal thermocouples. Next, the editor will briefly classify these graduation marks into different types.

S division number: It has strong oxidation resistance and high accuracy, and is commonly used as a standard thermocouple.

R scale: Many of its performance is basically the same as S scale, except that the electromotive force is about 0.15 greater than S.

B division mark: It can be used under oxidative conditions or for a short period of time under vacuum conditions, but its electromotive force is very small at indoor temperature.

N division mark: able to withstand low temperatures and radiation, with relatively stable thermoelectric potential and strong antioxidant capacity.

K scale: It has strong antioxidant properties and can be continuously used under oxidative conditions, with a particularly wide range of applications.

E division number: Very high sensitivity, can be continuously used in an oxidizing atmosphere.

J division number: It can not only be used in oxidizing and reducing atmospheres, but also has good corrosion resistance.

T division number: It belongs to the category of low-cost metal thermocouples with good accuracy.