Thermometers with Surface Emission of Infrared
Any infrared measuring instrument obtains equipment temperature information by measuring the surface infrared radiation power of electrical equipment. And when the infrared diagnostic instrument receives the same infrared radiation power from the target, different detection results will be obtained due to the different surface emissivity of the target. That is to say, with the same radiation power, the lower the emissivity, the higher the temperature will be displayed. The surface emissivity of an object mainly depends on the material properties and surface state (such as surface oxidation, coating material, roughness, and pollution state).
Therefore, in order to accurately measure the temperature of electrical equipment using infrared thermal imaging instruments, it is necessary to know the emissivity value of the tested target and input this value as an important parameter for calculating temperature into the computer or adjust the infrared measurement instrument's ε Correct the value to correct the emissivity of the measured temperature output value. The other two countermeasures to eliminate the impact of emissivity on the detection results are: when using an infrared thermal imager for measurement, the emissivity should be corrected by checking the emissivity value on the surface of the tested equipment components, in order to obtain reliable temperature measurement results and improve the reliability of the detection; For equipment components with frequent faults in infrared detection, in order to ensure good comparability of detection results, the method of applying appropriate paint can be used to increase and stabilize their emissivity values, in order to obtain the tested equipment
The true temperature of the surface.
Slope is the ratio of emissivity in monochromatic broadband temperature measurement mode to emissivity in monochromatic narrowband temperature measurement mode, which is used when calculating the measured temperature in dual color temperature measurement mode. Due to the inability to adjust the emissivity of narrowband mode, monochromatic broadband emissivity is used to divide
Calculate based on the slope value.
If you need to pay attention to the narrowband temperature, adjust the slope and broadband emissivity to make the narrowband emissivity greater than 1.00 (or less than 0.10).
Emissivity is a measure of the ability of an object to radiate infrared radiation. This value can range from 0 (mirror) to 1.0 (blackbody). If the emissivity setting is greater than the actual emissivity, the reading of the sensing head will be low. For example, if the actual emissivity of an object is 0.9 and the set value is 0.95, the measured temperature will be low.
