Emissivity; Reflection Temperature - Fluke Ti300U User Manual

Emissivity

Emissivity refers to the ratio of the energy radiated by the object under measurement to the energy
radiated by a black body at the same temperature and wavelength, and it is between 0 and 1.
All objects radiate infrared energy. The actual surface temperature and emissivity of the target affects
the quantity of energy radiated. The Imager senses the infrared energy from the surface of the target
and uses the data to calculate an estimated temperature value. Many common materials such as
wood, water, skin, cloth, and painted surfaces, including metal, radiate energy well and have a high
emissivity factor of ≥90 % (or 0.90). The Imager measures temperatures accurately on targets with a
high emissivity.
Shiny surfaces or unpainted metals do not radiate energy well and have a low emissivity factor of
<0.60. For the Imager to calculate a more accurate estimate of the actual temperature of targets with
a low emissivity, adjust the emissivity setting.
To prevent personal injury, see emissivity information for actual temperatures.
Reflective objects result in lower than actual temperature measurements. These
objects pose a burn hazard.
The emissivity settings of this series Thermal Imagers are divided into Full-Image Emissivity
Correction and Area Emissivity Correction. For the settings of the Area Emissivity Correction, see
Temperature Measurement Region
To Set Full-Image Emissivity:
1. In the Parameters menu, select Emissivity.
2. To customize material emissivity, slide up and down the emissivity values (0.01 to 1.0) on the left
side of the screen.
3. If the material of the target under measurement is known, you can slide up and down the Material
Emissivity Reference Table on the right side of the screen to select the corresponding material.
F2
4. Push (Last) to return to the previous menu, or push
directly.

Reflection Temperature

Reflection Temperature compensates or corrects the reflected thermal radiation on the target under
measurement. When the target is surrounded by very hot or very cold objects, the measurement
accuracy may be affected, especially when the surface emissivity of the target is low. Adjust the
reflected background temperature to improve measurement accuracy.
To set Reflection Temperature:
1. First use the Imager to test the actual temperature of reflectors near the target.
2. Select Reflection Temperature.
3. Slide the screen up and down to set the Reflection Temperature to the temperature value of the
reflector measured by the Imager.
F2
4. Push (Last) to return to the previous menu, or push
 Warning
(ROI).
F3
(Cancel) to exit the menu
F3
(Cancel) to exit the menu.
Thermal Imagers
System Menu
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