The application of the infrared pyrometer is mainly determined by the measurement range. Whether it is the measurement voltage or the initial value of the measurement area, it should be consistent with the requirements of the measurement work. The larger the measurement voltage is, the smaller the resolution and the lower the accuracy. If a large measurement voltage is used, the accuracy will be doubled, so it is recommended to choose the smallest possible measurement voltage.

The initial value of the measurement area determines the sensitivity of the spectrum, and even determines the type of the detector. The measurement error is significantly smaller than that of the long-wave sensor in the short-wave sensor due to the wrong adjustment of the emissivity. Therefore, in the hot film sensor ( 8～14μm) At 800℃, the measurement error caused by the wrong adjustment of the emissivity will be five times larger than that of the germanium-photodiode sensor (1, 1～1, 6μm). The permissible measuring range of germanium-photodiode sensors is from about 250°C.

Another criterion for selecting a suitable pyrometer is the spacing ratio. This refers to the proportional relationship between the measurement distance and the diameter of the measurement point. If the measured object is small, the measurement distance is large, or the so-called "hot spot" is in a large area, then a large spacing ratio is required. On the contrary, if the measurement point is large in area, because the sensor has a stable output signal to the measurement point value, it is fixed to use a small distance ratio.

In addition, it is necessary to determine whether the infrared pyrometer is equipped with an aiming device, because the aiming device will increase the cost by 50%. The key here is the subordinate of a price. When measuring a large area of ​​​​the object, it is usually not necessary to assemble the aiming device. It is replaced by an external sight, which will be used for the correction of the infrared pyrometer during installation, so that there is a price advantage, and only one sight is required for many measurements.