LumaSense IGA 12-TSP, Manual

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IS 12-TSP / IGA 12-TSP Manual Settings / parameter descriptions
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4.4 Emi (emissivity
ε
)
For a correct measurement it is necessary to adjust the emissivity. This emissivity is the
relationship between the emission of a real object and the emission of a black body radiation
source (this is an object which absorbs all incoming rays and has an emissivity of 1 = 100%) at
the same temperature. Different materials have different emissivities ranging between 0% and
100% (settings at the pyrometer between 10 and 100%).
Additionally the emissivity is depending on the surface condition of the material, the spectral
range of the pyrometer and the measuring temperature. The emissivity setting of the pyrometer
has to be adjusted accordingly. Typical emissivity values of various common materials for the
two spectral ranges of the instruments are listed below. The tolerance of the emissivity values
for each material is mainly dependent on the surface conditions. Rough surfaces have higher
emissivities.
Measuring object
Emissivity
ε
(at 0.65 µm)
Emissivity
ε
(at 0.94 µm)
Emissivity
ε
(at 1.57 µm)
„Black body furnace“ 1 1 1
Steel heavily scaled 0.92 0.93 0.85 to 0.9
Steel rolling skin 0.89 0.88 0.8 to 0.88
Steel, molten 0.35 0.3 0.2 to 0.25
Slag 0.85 0.85 0.8 to 0.85
Aluminum, bright 0.13 0.15 0.1
Chromium, bright 0.32 to 0.35 0.28 to 0.32 0.25 to 0.3
Brass oxidized
(tarnished)
0.7 to 0.8 0.65 to 0.75 0.6 to 0.7
Bronze, bright 0.04 0.03 0.03
Copper, oxidized 0.89 0.88 0.7 to 0.85
Copper, bright 0.15 0.03 0.02
Zinc 0.6 0.58 0.45 to 0.55
Nickel 0.24 0.22 0.15 to 0.2
Gold, bright 0.1 0.02 0.02
Silver, bright 0.02 0.02 0.02
Porcelain glazed 0.6 0.6 0.6
Porcelain rough 0.8 to 0.9 0.8 to 0.9 0.8 to 0.9
Graphite 0.82 to 0.93 0.8 to 0.92 0.8 to 0.9
Fireclay 0.45 to 0.6 0.45 to 0.6 0.45 to 0.6
Stoneware, glazed 0.86 to 0.9 0.86 to 0.9 0.8 to 0.9
Brick 0.85 to 0.9 0.85 to 0.9 0.8 to 0.9
Soot 0.95 0.95 0.95
4.5 Exposure time (t
90
/ s)
The exposure time is the time interval when the measured temperature has
to be present after an abrupt change so that the output value of the
pyrometer reaches a given measurement value. The time taken is to reach
90% of the recorded temperature difference. In the “0.00” position
(Software InfraWin: „min“), the device operates using its time constant.
The dynamic exposition time adjustment prolongs the exposure time at the lower range limit.
Settings:
0.00 s
0.01 s
0.05 s
. . .
10.00 s