IR-PAD SERIES USER MANUAL
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A CHART CONTAINING COMMON EMISSIVITY VALUES APPEARS ON THE
NEXT PAGE.
SURFACES WITH AN EMISSIVITY OF < 0.60 MAKE RELIABLE AND CONSISTENT
MEASUREMENTS PROBLEMATIC. THE LOWER THE EMISSIVITY, THE GREATER
POTENTIAL FOR ERROR WITHIN THE DEVICE’S CALCULATIONS. ERRORS MAY
STILL OCCUR EVEN WHEN ADJUSTMENTS ARE PERFORMED PROPERLY.
9-2-1 Detail Parameters
Name, Date, and Time information is automatically recorded and stored when
and image is captured. Images have a default name of “XXYZ_IR” where “X” is
a series of numbers. Users can enter notes in the Comments section. Location/
GPS is captured if enabled.
9-2-2 Emissivity
Users are provided the capability to enter any value of surface optical property
of the target surface deemed appropriate to the analysis. To set the emissivity
enter a value from 0.01 to 1.0 in the input box.
The correct emissivity value is important in order to receive the most accurate
temperature measurement. Emissivity of a surface can have a large effect
temperatures the imager observes.
To more accurately measure materials with a low emissivity, an emissivity
correction is necessary. Adjusting the emissivity setting will allow the imager to
calculate a more accurate estimate of the actual temperature.
All objects radiate infrared energy. The amount of energy radiated varies based
on the actual surface temperature and the surface emissivity of the object. The
Thermal imager senses the infrared energy from the surface of the object and
uses this data to calculate an estimated temperature value.
Many common objects and materials such as painted metal, wood, water, skin,
and cloth are particularly good at radiating energy and it is easy to get relatively
accurate measurements. For surfaces that are good at radiating energy (high
emissivity), the emissivity factor is >=0.90. This simplification does not work on
shiny surfaces or unpainted metals as they have an emissivity of <0.6. These
materials are not good at radiating energy and are classified as low emissivity.
AS THE EMISSIVITY VALUE BECOMES LOWER THE ERROR BETWEEN THE
ACTUAL SURFACE TEMPERATURE OF THE OBJECT AND THAT SHOWN
BY THE CAMERA BECOMES GREATER. A GREAT DEAL OF ERROR CAN BE
INTRODUCED INTO THE CALCULATION PROCESS IF YOU ARE NOT CAREFUL
WITH THE EMISSIVITY SPECIFICATION.
