Sonel DIT-500 Manual De Uso página 36

accuracy is critical, make sure the target is at least twice as
large as the spot size.

Distance and spot size
As the distance (D) from the object increases, the spot size
(S) of the area measured by the unit becomes larger.

Locating a hot Spot
To find a hot spot aim the thermometer outside the area of in-
terest, then scan across with an up and down motion until you
locate hot spot.

Reminders
- Not recommended for use in measuring shiny or polished
metal surfaces (stainless steel, aluminum, etc.). See Emis-
sivity.
- The unit cannot measure through transparent surfaces such
as glass. It will measure the surface temperature of the glass
instead.
- Steam, dust, smoke, etc., Can prevent accurate measure-
ment by obstructing the unit's optics.

Emissivity
Emissivity is a term used to describe the energy-emitting
characteristics of materials.
Most (90% of typical applications) organic materials and
painted or oxidized surfaces have an emissivity of 0.95 (pre-
set in the unit). Inaccurate readings will result from measuring
shiny or polished metal surfaces. To compensate, cove the
surface to be measured with masking tape or flat black paint.
Allow time for the tape to reach the same temperature as the
material underneath it. Measure the temperature of the tape
or painted surface.
The DIT-500 can compensate additional error of emissivity
other than 0.95. In this purpose, enter correct value of meas-
ured substance emissivity.
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DIT-500 – USER MANUAL