IMPAC pyrometers series IN 5 plus
17
Measuring object
Emi (at 8 ... 14 µm)
Measuring object
Emi (at 8 ... 14 µm)
"Black body furnace"
100%
Brickwork
Human skin
98%
Fire clay
Black dull varnish
95%
Rubber
Carbon soot
95%
Porcelain
Wood
80 to 92%
Ceramics
Paper
92 to 95%
Varnish
Asphalt
85%
Plaster
Glass / quartz glass
72 to 87%
Oil paint
85 to 95%
Textile
75 to 95%
Steel (oxidized)
60 to 80%
Graphite
75 to 92%
Steel (smooth)
10 to 30%
Cement
90%
Aluminum (smooth)
2 to 15%
Water
95%
Aluminum (anodized)
90%
Measuring object
Emi (at 5.14 µm)
Glass / quartz glass
97%
One way to determine an accurate emissivity value for a material is to make a comparison measurement as
follows: If possible, coat a portion of the object with dull black paint or carbon soot. Paint and carbon soot
have high emissivities (95%) and take on the same temperature as the object. Measure the temperature of
the painted area with the emissivity control set to 95%. Then measure the temperature of an adjacent un-
painted area of the object and adjust the emissivity until the pyrometer displays the same temperature.
Setting examples at the instrument: Emi = 100%:
Emi = 85%:
If the settings directly at the pyrometer should be used the pyrometer must be switched into offline mode
(OFFL, see 8.2). To adjust the emissivity via software see section 10, Settings via interface / software).
Note:
If the emissivity is set to a incorrect value (below 20%) the instrument will
automatically utilize an emissivity value of 100%. The setting 00 is interpreted as
Emi = 100%.
9.1.2
Exposure time t
90
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. Slower response time can
be an advantage when trying to measure an object that has
a rapidly fluctuating temperature.
To change the exposure time the corresponding DIP switch
for 0.5 s, 1 s, 2 s or 5 s must be set in the ON position. A
longer response time of 10 s can be set if the switch for
0.5 s and 5 s is set to the ON position at the same time, a
longer response time of 30 s can be set if the switch for 1 s and 5 s is set at to the ON position the same
time. In the “OFF” position (Software InfraWin: t
90
= min), the device operates using its time constant (see
technical data).
If the settings directly at the pyrometer should be used the pyrometer must be switched into offline mode
(OFFL, see 8.2). To adjust the exposure time via software see section 10, Settings via interface / soft-
ware).
Example: t
90
= 1 s Example: t
90
= 5 s
0.5 s
1 s
2 s
5 s
4/0mA
ONL/OFFL
Emi
x10 x1
O
N
D
IP
1 2 3 4
5 6
0.5 s
1 s
2 s
5 s
4/0mA
ONL/OFFL
Emi
x10 x1
O
N
D
IP
1 2 3 4
5 6
Setting examples at the instrument:
