How to Set Slope and Emissivity for Infrared Thermometers
How to determine the slope
Effective methods for determining slope include using probes (such as RTDs), thermocouples, or other suitable methods to measure object temperature. After the actual temperature is obtained, adjust the emissivity setting until the temperature reading of the sensor head is equal to the actual measured temperature, which is the correct slope value.
How to determine emissivity
1. Use probes (such as RTD), thermocouples, or other suitable methods to determine the actual temperature of an object. Adjust the emissivity value until the temperature reading of the sensing head matches the actual temperature, which is the correct emissivity.
2. If a part of the surface of the object can be coated, the surface of the object can be coated with matte carbon black. At this time, the emissivity is about 0.98. Set the emissivity to 0.98 and measure the temperature of the blackened part. *Then measure the area adjacent to the blackened part on the object and adjust the emissivity until the temperature reading matches the actual temperature. At this point, the correct emissivity is obtained.
Optimize the measurement of surface temperature based on the following criteria:
1. Use measuring instruments to determine the emissivity of objects.
2. Try to avoid reflection as much as possible; Shield the object from high-temperature heat sources in the surrounding environment.
3. When the temperature of an object is high, if there are several overlapping wavelengths that can be used, choose a shorter wavelength.
4. For semi transparent materials such as glass; When measuring temperature, it should be ensured that the background temperature is uniform and lower than the temperature of the object.
5. When the emissivity is less than 0.9, the sensing head should be kept as perpendicular as possible to the surface of the target object. Do not make the angle between the axis of the sensing head and the normal of the object surface greater than 45 °
