Dynamic Adaptation At Low Signal Levels (Only M3 Devices); Peak Picker Storage Mode / Clear Time; Emissivity Slope - KPM PROCESS SENSORS METIS M311 Operating Manual

The response time t
change on the signal output.
The response time depends on the requirements of the respective measuring task and can be adjusted.
▪ If a short response time is selected, the temperature measurement follows the actual temperature curve ac-
curately. Short setting thus allowing the detection of briefly occurring temperature peaks, which occur espe-
cially in fast heating processes or fast moving targets.
▪ At longer response times, the measurement signal is smoothed and average values for temperature fluctua-
tions are formed caused by the inertial measurement.

6.2.1.1 Dynamic Adaptation at Low Signal Levels (only M3 devices)

All pyrometers have low signal levels at the beginning of the temperature range. At the highest measuring
speed this would lead to signal noise and thus the risk of measurement uncertainties. To prevent this, the de-
vices measure a little more slowly in the first 10-15% of its temperature range. How much slower differs de-
pending on the temperature range of the models and is also dynamically adjusted, the higher the beginning of
the temperature range is. As soon as this 10-15% is exceeded, the devices measure with their full response
time.

6.2.2 Peak Picker Storage Mode / Clear Time

The peak picker always records the highest value during a measurement and holds it until it is deleted manu-
ally or automatically:
Off:
Clear externally: The maximum value is cleared manually by an external button or machine contact (connec-
Automatically:
Time 0.01...25 s: Clears the maximum value after the specified time.
Trigger:

6.2.3 Emissivity Slope

Measuring objects that emit the same on the two wavelengths of a 2-color pyrometer are often referred to as
"Gray bodies" (e.g. well oxidized iron or steel surfaces). They can be measured accurately with the setting 1.00
for the emissivity slope without correction.
Measuring objects whose emissivity is different on the two wavelengths of the pyrometer (e.g. shiny unoxidized
metal surfaces) need for accurate temperature measurement a correction setting, the so-called emissivity
slope Ɛ / Ɛ
. The value can be larger or less than 1, depending on whether the emissivity of channel 1 or 2 is
2 1
higher.
▪ 0.800–1.000: gain, temperature display will be higher
▪ 1.000–1.200: Attenuation, temperature display will be lower
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specifies the time that the pyrometer requires to track 90% of a sudden temperature
90
The peak picker storage is off and the instantaneous value is measured.
tion see 4.1.4 Configurable Inputs / Outputs). The external clearing also can be carried out
with the command lx (see 11, Communication via Serial Interface / Interface Com-
mands).
The maximum value is cleared, if after a "cold break" a new hot measuring object appears in
the measuring beam. "Cold break" means that the measuring temperature must be below of
the beginning of the temperature range. The "cold break" must correspond to at least the
length of the set response time.
INFO
If Clear Times are too long, important temperature information can be lost at sinking
temperatures).
The maximum value is manually generated via an external button or machine contact, as
long as the trigger contact is active. The maximum value display appears after releasing the
button.
METIS M311 / M322 / H311 / H322 (12-pin device connector)