① High measurement accuracy. Because the thermocouple is directly in contact with the measured object, it is not affected by the intermediate medium.

② Wide measuring range. Commonly used thermocouples can be continuously measured from -50 to +1600 ° C, and some special thermocouples can be measured as low as -269 ° C (such as gold and iron nickel chromium) and as high as +2800 ° C (such as tungsten-rhenium).

③ Simple structure, easy to use. Thermocouples are usually composed of two different kinds of wire, and are not limited by size and beginning, and have protective sleeves outside, which is very convenient to use.