METIS M308 / M309 / M313 / M316 / M318 / M323 / H309 / H316 / H318 (12-pin)
Configuring the Pyrometer
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texture alloy components
play an important role for
the emissivity.
Is a range given, this is
related to differences in
the nature of the sur-
face from smooth to
rough, rough surfaces
have higher emissivities
(for determining the cor-
rect emissivity also a
comparison measure-
ment can be performed
with a thermocouple).
The emissivities with
"shiny" refer to applica-
tions that are performed
under an inert gas or in
a vacuum.
“n.s.“ means that no
values exist for this
wavelength range (not
specified), e.g. because
a reasonable meas-
urement in this wave-
length or temperature
range is not possible.
Measurement deviations at a 10% false set
emissivity at a temperature of 700°C:
Materials has a maximum emissivity of 1 (100%). However, a setting of up to 1.2 can be used to com-
pensate for temperature corrections due to higher background reflection.
To determine the correct emissivity, also a comparative measurement with a thermocouple can be per-
formed.
6.3.4 Transmittance
Is a viewing window located between measuring object and pyrometer, the transmittance of the window
must be considered during the measurement. Enter the transmittance of the window in order to obtain a
correct measurement result.
6.3.5 Spot Size Fill Factor
Measurements of objects that are smaller than the pyrometer’s spot size can be performed when meas-
uring hot objects in front of a cold background. In this case the fill factor specifies how much percent the
measuring field is filled (see also 5.4 Alignment to the measuring object).
INFO: Emissivity, transmittance and spot size fill factor are directly related to each other, the re-
sult of the multiplication of the 3 parameters has to be minimum 5%.