Thermometer determines the emissivity of the object being measured
Emissivity reflects an object's ability to radiate infrared light. Therefore, the influence on the measured temperature caused by different objects having different emissivities must be compensated according to the set emissivity. The main factors that affect emissivity are: material type, surface roughness, physical and chemical structure, and material thickness. Figure 1 lists the emissivities of common materials for easy reference. The emissivity of some other engineering objects can also be found in relevant literature. For objects with unknown emissivity, you can first use a contact thermometer to measure the surface of the object, and then use an infrared thermometer to measure the surface of the object. At the same time, adjust the emissivity so that the measured temperature is consistent with the temperature of the contact thermometer. The emissivity at this time is the emissivity of the measured object. Silver powder is often used as anti-corrosion for equipment shells. It looks like paint but not paint. It is composed of zinc powder and a blender, which is different from ordinary paint. Its emissivity is rarely introduced in the data. You can use the following method to measure its emissivity: heat it in the laboratory, use a thermal resistance device to measure the surface temperature of the silver powder, and then adjust the emissivity. When the temperature of the thermometer and the thermal resistance When the measured temperatures of the devices are similar, the emissivity is the emissivity to be measured. In fact, many units are still using portable thermometers whose emissivity cannot be adjusted. When measuring temperature, the corresponding emissivity cannot be adjusted according to the material of the object, and the error is too large.
Cleaning the lens and calibrating the thermometer
After the thermometer is used for a period of time, dust will accumulate on the lens, which is easily overlooked. You can use a cleaning ball to blow off surface dust or use a clean cotton swab dipped in a little water to clean the lens surface. Otherwise, the temperature displayed by the thermometer will be lower than the actual temperature of the target being measured. Infrared thermometers must be calibrated regularly so that they can correctly display the temperature of the target being measured. If the temperature measurement of the thermometer used is out of tolerance during use, it must be returned to the manufacturer or maintenance center for recalibration.
