METIS M311 / M322 / H311 / H322 (17-pin)
Pyrometer Parameters / Settings
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as possible, as here the emissivity is
higher than in the long-wave range.
The specified values are guide values,
which were determined in the laborato-
ry and confirmed in application-
oriented measurements. They can
vary due to material-dependent condi-
tions, as in metals additionally to the
surface 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 correct emis-
sivity also a comparison measure-
ment can be performed with a ther-
mocouple).
“n.s.“ (not specified)means that no
values exist for this wavelength
range , e.g. because a reasonable
measurement in this wavelength or
temperature range is not possible.
The emissivities with "shiny" refer to
applications that are performed un-
der an inert gas or in a vacuum.
Measurement deviations at a 10% false set emissivity
at a temperature of 700°C:
6.3 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.
6.4 Spot Size Fill Factor
Entering a fill factor that indicates how much percent of the measuring field is filled, has no influence if
using the 2-color measuring mode (see also 5.4 Alignment to the Measuring Object).
In 1-color mode: Measurements of objects that are smaller than the pyrometer’s spot size can be per-
formed when measuring hot objects in front of a cold background. In this case the fill factor specifies
how much percent the measuring field is filled.
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%.
6.5 Switch-off Level
2-color pyrometers measure even with reduced signal strength, such as those occur in a partially filled
measuring field, or dust, smoke, steam, or a window in the beam path between pyrometer and the
measuring object. If the signal strength is too low for a reliable measurement, the measurement is
switched off to avoid measurement errors. In this case the current output can be set to 0 or 4 mA or
20 mA, and also serial interface settings can be defined.