Response Time T; Dynamic Adaptation At Low Signal Levels (Only M3 Devices); Storage Mode Peak Picker (Maximum Value Storage) / Clear Time T; Emissivity Ɛ - KPM PROCESS SENSORS METIS M308 User Manual

METIS M308 / M309 / M313 / M316 / M318 / H309 / H316 / H318 (12-pin)

6.3.1 Response Time t

The response time specifies the time that the pyrometer requires to track 90% of a sudden temperature 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
accurately. Short setting thus allowing the detection of briefly occurring temperature peaks, which occur
especially in fast heating processes or fast moving samples.
▪ At longer response times, the measurement signal is smoothed and average values for temperature
fluctuations are formed caused by the inertial measurement.

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

At the beginning of the temperature range at high measurement speeds, the risk of measurement uncertainty is
given by signal noise. This is compensated by the pyrometer by automatically increasing the response time at
the beginning of the temperature range from 1 ms to 4, 8 and finally 16 ms.

6.3.2 Storage Mode Peak Picker (Maximum Value Storage) / Clear Time t

The maximum value storage always records the highest value during a measurement and holds it until it is de-
leted manually 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:
6.3.3 Emissivity Ɛ
The emissivity indicates the radiation capacity of an object to be measured relative to a black body source with
the same temperature. To obtain correct readings, the emissivity must be taken into account in the measure-
ment and adapted for the respective measuring material on the pyrometer.
In principle applies: to
measure metals in a short-
wavelength spectral range
as possible, as there the
emissivity is higher than in
the long-wave range.
The specified values are
guide values, which were
determined in the labora-
tory and confirmed in ap-
plication-oriented meas-
urements. They can vary
90
The maximum value 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
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|
At too long clear times important temperature information can be lost at sinking tem-
peratures).
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.
Measuring object
Black body source
Aluminum, shiny
Aluminum, oxidized
Alu, sandblasted, rough
Alu, black anodized
Lead oxidized
Bronze
Iron, liquid
Iron, shiny
(see 11, Communication via Serial Interface / Interface Com-
M308/09
H309
1
n.s.
n.s.
n.s.
n.s.
n.s.
0.2-0.4
0.15-0.3
0.3-0.4
CL
Emissivity Ɛ (Epsilon)
M316 M318
H316 H318
1 1
0.05-0.2 0.02-0.4
0.3-0.4 0.3-0.65
0.4-0.5 0.4-0.7
0.9 0.9
n.s. 0.2-0.7
0.2-0.4 n.s.
0.1-0.25 0.1-0.2
n.s. n.s.
M323
1
0.01-0.2
0.3- 0.5
0.3-0.5
0.8-0.9
0.4-0.7
n.s.
n.s.
0.2-
29