There are thousands of pyrometers, which can be divided into two categories: contact and non contact pyrometer. Today, let me introduce the advantages and disadvantages of each of them.

Generally speaking, contact pyrometers are relatively simple, reliable, and have high measurement accuracy; but because the temperature measurement element and the measured medium need to be fully thermally exchanged, and it takes a certain time to reach thermal equilibrium, there is a delay in temperature measurement. At the same time, it is limited by high temperature resistant materials and cannot be used for high temperature measurement.

The non contact pyrometer measures temperature, for example, infrared pyrometer measures temperature through the principle of thermal radiation. The temperature measuring element does not need to be in contact with the measured medium. The non contact pyrometer has a wide temperature measurement range and is not limited by the upper limit of temperature measurement. The pyrometer will not destroy the temperature field of the measured object, and the reaction speed is generally relatively fast; but due to the influence of external factors such as the emissivity of the object, the measurement distance, smoke, and moisture, the measurement error is relatively large.

Therefore, the non-contact pyrometer is generally selected for high temperature measurement; in terms of accuracy, the contact type is generally selected.