7.3. Locating a hot Spot
To find a hot spot aim the thermometer outside the area of
interest, then scan across with an up and down motion until you
locate hot spot.
Reminders
1. The unit cannot measure through transparent surfaces such
as glass. It will measure the surface temperature of the glass
instead.
2. Steam,
dust,
smoke,
etc.
can
prevent
accurate
measurement by obstructing the unit´s optics.
7.4. Emissivity Values
Material
Condition
Temperature-Range Emissivity-
factor (ɛ)
Aluminium
polished
50°C … 100°C
0.04 ... 0.06
Raw surface
20°C … 50°C
0.06 ... 0.07
oxidized
50°C ... 500°C
0.2 ... 0.3
Aluminium
oxide,
Aluminium
powder
normal Temperature
0.16
Brass
matt
20°C ... 350°C
0.22
oxidized at
600°C
200°C ... 600°C
0.59 ... 0.61
Polished
200°C
0.03
Wrought with
sandpaper
20°C
0.2
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