1 slope adjustment, 2 temperature errors cause by non-graybodies – LumaSense Technologies ISR 6 Advanced User Manual
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ISR 6 Advanced Manual
Settings / parameter descriptions · 22
using a thermocouple probe or by knowing one process temperature point precisely from other
sources. The K-factor can then be adjusted until the pyrometer shows the same temperature
value.
The ISR 6 is factory calibrated for graybody targets that exhibit equal changes in emissivity
within its two spectral bands.
Note: Emissivity Slope K Settings: 0.800 to 1.200 in steps of 1/1000 (2-color mode).
4.3.1 Slope Adjustment
In some cases the emissivities of the two wavelengths can differ so that it is necessary to correct
the ratio of the two emissivities (K = e1 / e2) to get a correct temperature reading. This
correction can be done by adjusting the emissivity slope setting K using the InfraWin software or
the UPP data format commands.
The K-factors of metals are normally slightly higher than 1. For a correct measuring result, it is
recommended that you make a comparison test. This comparison test may be performed by
using a thermocouple probe or by knowing one process temperature point precisely from other
sources. The K-factor can then be adjusted until the pyrometer shows the same temperature
value.
The ISR 6 Advanced is factory calibrated for graybody targets that exhibit equal changes in
emissivity within its two spectral bands.
4.3.2 Temperature Errors Cause by Non-Graybodies
A graybody target has emissivity that is the same at each of the two wavelengths used for
measurements and is constant throughout the temperature range. The ratio of the emissivities,
e1 / e2= 1 and stays constant regardless of the target temperature. When a target deviates from
this, that is when e1 / e2 does not equal 1.0 and a slope adjustment is required. For many
materials, this is a one-time adjustment.
The following table illustrates the ISR 6 reading errors that can occur when the slope setting
differs from the actual material emissivity ratio.
TABLE OF EXPECTED ERROR WHEN EMISSIVITY OF ONE
WAVELENGTH IS 1% DIFFERENT FROM THE SECOND WAVELENGTH
TEMPERATURE
ERROR DEG.
°F
°C
°F
°C
1300
700
18
10
1500
815
20
11
1700
926
22
12
1900
1040
25
14
2100
1150
25
14
2300
1260
27
15
2500
1370
29
16
3000
1650
36
20
3500
1925
45
25
4000
2200
54
30
5000
2760
72
40