LumaSense Technologies IS 12-TSP - Handbuch (Seite 14)

IMPAC pyrometers IS 12-TSP · IGA 12-TSP
14
8.3 Factory settings
Emissivity (

) = 1,000
Exposure time (t
90
/ s) = 1 s
Clear time (t
CL
) = 0,00 (= OFF)
Sub range (from / to) same as temperature range
Analog output (0 / 4 mA) = 0 ... 20 mA
Limit contacts = end of temperature range
Hysteresis = ±2°C
Temperature display (°C / °F) = °C
Interface (RS) = RS232
Address (ADR) = 00
Baud rate (kBaud) = 19,2 kBd
Test current output (10 mA) = off
9 Parameters
9.1
Emi (emissivity

)
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 ab-
sorbs 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 ac-
cordingly. Typical emissivity values of various common materials for the two spectral ranges of the instru-
ments 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 
(at 0.65 µm)
Emissivity 
(at 0.94 µm)
Emissivity 
(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
9.2
t
90
/ s (exposure time)
The exposure time is the time interval when the measured temperature has to be pre-
sent 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 differ-
ence. 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