Infrared thermometer (portable) is characterized by non-contact temperature measurement; wide temperature measurement range (600~1800℃/900~2500℃); high precision; stable performance; fast response time (O.7s); working distance greater than 0.5m, One of the necessary inspection tools for on-site inspection, the advantage is that it is easy to carry.

Optical pyrometers are simple in structure, lightweight and easy to use, and are often used in metal smelting, glass melting, heat treatment and other processes, and are non-contact temperature measurement. The disadvantage is that the measurement is compared by the human eye, which is easy to introduce subjective errors and the price is high.
 Thermocouples account for a large proportion of industrial temperature measurement. Thermocouples are mostly used for remote temperature measurement in the production process. The advantages are small size and easy installation; remote signal transmission can be used for display and control; compared with pressure thermometers, the response speed is fast; the temperature measurement range is wide; the temperature measurement accuracy is high; . The disadvantage is that the relationship between thermoelectric potential and temperature is nonlinear; the accuracy is lower than that of resistance; under the same conditions, the thermocouple contact is easy to age. In field use, thermal resistance is generally used when the temperature is less than 300°C, and thermocouples are mostly used when the temperature is higher than 300°C. Thermal resistance is often used for low-pressure steam.