Sensor Therm METIS MF11, Operation Manual

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METIS MF11
Device Parameters
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be reached with channel 1 and 2 by changing their Epsilon settings till they agree. If both of the so found emis-
sivity factors are the same, then the object is a gray body.
If temperature readings of channel 1 and 2 agree with ratio mode, but their Epsilon settings are different, then
the object is a “none grey body”. These objects or targets have to be tested by measuring their temperature with
T/C and then the Epsilon slope setting has to be changed to read the same temperature.
Emissivity ε (Epsilon):
Setting range 20-100%
The table for the mean effective wavelength

= 0.9 µm is valid only when Metis MF11 is operated in the partial
radiation mode K1+K2. In addition, the Metis MF can also record and display the results of the short wave in
partial emission mode (channel 2) or in the long wave spectral range (channel 1).
List of commonly used materials:
Object Metis MF
Black body 1
Iron heavily scaled 0.93
Iron rolling skin 0.88
Iron molten 0.3
Slag 0.85
Aluminum 0.15
Chromium bright 0.28...0.32
Brass oxidized (tarnished) 0.65...0.75
Bronze 0.03
Copper oxidized 0.88
Zinc 0.58
Nickel 0.22
Gold, Silver, blank 0.02
Porcelain glaced
Porcelain rough 0.6
0.8...0.9
Graphite 0.8...0.92
Chamotte 0.45...0.6
Earthenware glazed 0.86...0.9
Brick 0.85...0.9
Soot 0.95
These emissivities apply for mean effective wavelengths

=0.9 µm for Metis MF Differences in surface finishes
or roughness may cause deviations.
Reduction Ratio
– setting values: 2 – 50%
In this case, you have the possibility in ratio mode to set the maximum signal reduction which causes the switch-
ing off of the temperature measurement. The setting values correspond to a signal reduction of 50
– 98%. Some
reasons for signal reduction: lower emissivity factor than 1 or 100%, a measuring area that is only partially filled,
dust, smoke, steam or a window in cone of vision between pyrometer and object.
The factory setting is 5% and permits, for example, the reduction of the measuring field of a calibration body with
an emissivity of 1.00 (100%) at 95%. The displayed temperature is not modified in the process.
t
90
(exposition time)
Setting values: 5 ms (min), 10 ms, 50 ms, 250 ms, 1 s, 3 s, 10 s.
At exposition time set
ting “min” the device works with its intrinsic exposition time.
The dynamic exposition time adjustment extends the exposition time at the lower range limit.
If the maximum value storage is selected and the measuring object has a low emissivity and the measuring tem-
perature is at the beginning of the range, a higher response time must be chosen to prevent measurement er-
rors.
Longer exposition times (input in seconds) may be useful for averaging over fast changes of the object tempera-
ture.