How to Choose an Infrared Thermometer

Infrared temperature measurement technology is an important means of product quality control and monitoring, and also an important guarantee for online fault diagnosis and safety protection of equipment. Infrared thermometers based on this technology are more and more concerned and favored by various substations, power plants, and oil refineries.  

With the increase in demand, manufacturers of infrared thermometers are also blooming everywhere. However, due to the limitation of funds and scientific research strength, many manufacturers produce products with poor quality, short service life and low measurement accuracy. Therefore, users must be cautious when purchasing infrared thermometers, and must conduct on-site inspections, considering the following factors:        

1. Temperature measurement range.

The temperature measurement range is an important performance index of the thermometer, and each type of thermometer has its own specific temperature measurement range. Generally speaking, the narrower the temperature measurement range, the higher the resolution of the temperature monitoring output signal, the higher the accuracy, and vice versa, the lower the accuracy. The measurement range of TASI-8612 infrared micrometer is -50℃～900℃(-58℉～1652℉), and the measurement accuracy is ±1.5% or 1.5℃.  

2. Target size.

Infrared thermometers can be divided into single-color thermometers and two-color thermometers according to the principle. For monochromatic thermometers, when measuring temperature, the area of the target to be measured should fill the field of view of the thermometer. It is recommended that the size of the target to be measured exceeds 50% of the field of view. If the target size is smaller than the field of view, the background radiation energy will enter the visual and acoustic symbols of the thermometer and interfere with the temperature measurement readings, causing errors.  

3. Distance coefficient.

The distance coefficient is determined by the ratio of D:S, that is, the ratio of the distance D between the probe of the thermometer to the target and the diameter of the target to be measured. If the thermometer needs to be installed far away from the target due to environmental conditions, and the target to be measured is small, a thermometer with high optical resolution should be selected.  

4. Wavelength range.

Because some materials are transparent at certain wavelengths, infrared energy will pass through these materials, so special wavelengths must be selected. For example, 1.0μm, 2.2μm and 3.9μm are used for measuring the internal temperature of glass; 5.0μm is used for measuring glass surface temperature; 8-14μm is suitable for measuring low temperature area. The best wavelength for measuring metal materials is near-infrared, and 0.8-1.0 μm can be selected.  

5. Response time.

The response time indicates the reaction speed of the infrared thermometer to the measured temperature change. Some infrared thermometers have a response time of up to 1ms, which is much faster than the contact temperature measurement method. If the moving speed of the target is very fast or when measuring a fast-heating target, a fast-response infrared thermometer should be selected, otherwise the sufficient signal response will not be achieved, and the measurement accuracy will be reduced.  

6. Environmental conditions.

The environmental conditions of the thermometer have a great influence on the measurement results, which should be considered, otherwise it will affect the temperature measurement accuracy and even damage the instrument. When the ambient temperature is high and dust, smoke and steam exist, accessories such as protective cover, water cooling, air cooling system, and air blower provided by the manufacturer can be selected. These accessories can effectively address environmental influences and protect the thermometer for accurate temperature measurement.  

Although the price of an infrared thermometer is not high, it takes time and effort to choose a high-quality, high-precision instrument. Although there are many manufacturers nowadays, the quality of the products is uneven, and the performance is different. to have adverse effects.