7. Setup Menu Emissivity
Note: All menu settings are retained when the instrument is
switched off
Press the
MENU
button to enter the setup menu. Use
UP /
DOWN
navigation buttons to highlight EMS.
The current emissivity is displayed. Press the
Enter
button
and press the
UP / DOWN
navigation buttons to adjust
emissivity. Press the
MENU
button; the new value is now
stored and displayed. Press the
MENU
button again to exit
the setup menu.
7.1 Emissivity
Definition of emissivity is the ratio of the energy radiated from a material’s or object’s surface to that radiated from a
perfect emitter, known as a blackbody.
It is a value between 0 (for a perfect reflector) and 1 (for a perfect emitter).
The emissivity of a surface depends on two variables; the material and the nature of the surface itself. A polished metal
surface will have a low emissivity, while an oxidized metal surface will have a fairly high emissivity. The emissivity is also
dependent on the temperature of the surface.
Typically, 90% of organic materials and painted or oxidized surfaces have an emissivity of 0.95. Inaccurate readings
will result from measuring shiny or polished metal surfaces. To compensate, cover the surface to be measured with
masking tape or matt / flat black paint and allow time for the tape/paint to reach the same temperature as the material
underneath it. An accurate measurement can then be made of the taped/painted surface.
Set up menu options continued
Setup Menu Emissivity
10
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