Accurate emissivity must be set in order to accurately measure the temperature of the material surface with a radiation thermometer.
For that purpose, it is necessary to obtain the emissivity of the material, and there are three methods.
1. Compare with a contact thermometer (see diagram below)
The object to be measured that has been adjusted to the actual temperature
Measure at the same time with a calibrated contact thermometer and the radiation thermometer used.
Adjust the emissivity setting of the radiation thermometer so that the measured value of the radiation thermometer is equal to
the measured value of the contact thermometer.
2. Use black body tape or black body paint (spray) (see below)
Affix a black body tape or adjust the temperature of the measurement object coated with black body paint
to the temperature for actual measurement,
Measured with a radiation thermometer set to the emissivity of black body tape or black body paint (around 0.95).
So that the temperature display value of the part without black body tape and paint is the same as the measured value of the part with black body tape and paint
Adjust the emissivity setting of the radiation thermometer.
3. Research in the literature
Investigate the emissivity described in literature and the web.
However, with this method, the objects to be measured are not covered,
Please note that the values may vary depending on the surface condition, temperature, etc.
A list of representative emissivity for each material is posted in the ” What is emissivity? “article.
In our company, we offer products with adjustable (changeable) emissivity ranging from 0.10 to 1.00 in increments of 0.01.
These products include AD-5634, AD-5618, AD-5614, AD-5616, AD-5612WP, and AD-5612A.
We also provide a product, AD-5613A, which allows for setting (changing) the emissivity from 0.05 to 1.00 in increments of 0.01.
Additionally, we offer a product, AD-5635, which allows for selecting from emissivity options of 0.95, 0.70, and 0.30.
We also offer infrared thermometers that can be connected to separately sold thermocouple temperature sensors.
By using the method of “comparing with contact-type thermometers,” it becomes easy to set the emissivity.