Treatment Of Ir Thermometers - Fluke 4180 Technical Manual

Note that when an IR thermometer is calibrated against another IR thermometer that uses the same
temperature source, both should view the same portion of the electromagnetic spectrum. The Product
calibration uses a highly-accurate IR thermometer which operates in the 8 μ m to 14 μ m band. This
should be sufficient to calibrate IR thermometers using this bandwidth. If you need more information
about what band the device under test (DUT) operates in, consult the unit's user's guide or the unit's
manufacturer.
Radiometric calibration is to account for factors that cannot be accounted for with a contact calibration.
The two main factors are the difference between contact temperature and surface temperature, and
the difference between the DUT's emissivity setting and the target's surface emissivity. These factors
are discussed further in
thermometer used to calibrate the Product is 0.95.

Treatment of IR Thermometers

Three other issues require consideration when using or calibrating IR thermometers.
First, they are subject to thermal shock. If an IR thermometer is suddenly introduced to significantly
different ambient conditions, it should be allowed time to reach thermal equilibrium.
Second, IR thermometers are subject to measurement influence by ambient conditions and should be
calibrated under similar conditions as those under which they will be used.
Lastly, IR measurements can be influenced by the cleanliness of the IR thermometer's optics. They
should be cleaned regularly, including immediately prior to calibration. Check with your IR thermometer
manufacturer for proper cleaning methods.
Basic Infrared Thermometry Theory - Relating to the use of the Product
NIST
Fluke
Calibration
CL1
Fluke
Calibration
IR Cavities
4180 /4180
Figure 5. Product Traceability
Use of the Product in the Context of IR
Precision Infrared Calibrator
KEY:
Theory. The emissivity setting of the IR
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