Parameters - KPM PROCESS SENSORS PSC-S55N Operation Manual

PSC-55 Pyrometer Series Operation Manual

Parameters

Emissivity ε "Emissivity"
Ratio correction K "Ratio corr."
Intensity (read only)
Transmittance
Ambient radiation
You can adjust the following parameters via RS-485 interface:
The emissivity of a measuring object specifies how much radiation it emits compared
to an ideal heat radiator, a blackbody radiator, at the same temperature. According to
Kirchhoff's radiation law, absorption and emission capacity are equal. The black body
radiator has an emissivity of 1. In contrast, real measuring objects always have an
emissivity of < 1. This value should be known and should be adjusted at the pyrometer.
Emissivity charts can be found in literature /4/. Because the emissivity of a real body
is generally dependent on the wavelength too, the spectral range of the pyrometer has
to be considered as well when using the emissivity charts in citation.
You can adjust the emissivity of the pyrometer models PSC-S55N / PSC-G55N / PSC-
GE55N and (PSC-SR55N in 1-channel mode) in the range from 0.050 to 1.000. Please
note that an incorrectly set emissivity can lead to false measuring results. The effect
of the adjustment can be directly traced in the display of the temperature display.
.
(PSC-SR55N series only, 2-color / ratio mode)
Ratio pyrometers measure the radiation signal in two different but close to each other
spectral range und use the ratio of the radiation signal for the determination of the
temperature. If the measurement object has the same emissivity in both spectral
ranges, this value gets eliminated by ratio formation and a ratio correction is not
necessary. Especially for metals, the ratio is
Please note: This parameter has big influence on the measurement result so changes
should be made in small steps. The effect can be traced directly in the display of the
temperature display.
(PSC-SR55N series only, 2-color / ratio mode)
The intensity is a calculated quantity and a measure for the radiation intensity of the
measurement object. The radiation intensity is influenced by the emissivity and the
measuring field filling of the measurement object and by attenuations on the
transmission path to the pyrometer (dust, sighting windows and other).
If the intensity is 1.0 (100 %) 1 channel temperature and ratio temperature are equal,
which is the case at the black body radiator. In normal case the intensity is < 1.0.
If going below the minimum intensity
in ratio mode is set to measurement range start.
*) factory setting, changeable with software PSCspot (2 % to 50 %)
Please note: Adjustments of emissivity, transmittance and K factor influence the
calculation of the intensity so if the parameters are not adjusted plausibly intensities
> 1.0 (100 %) can be calculated (e.g. emissivity is too small and K factor is too high).
If you measure through a window, e.g. a vacuum flange, the signal attenuation can be
balanced with this parameter. The transmission value of the window material is
specified in percent %.
(Not available for the PSC-SR55N series)
All measuring objects with an emissivity of < 1 external reflection radiation from their
ambient surrounding are measured. In this way the measuring signal gets falsified.
The ambient compensation prevents this influence. In doing so, the ambient
temperature of the measuring object is specified (within the temperature range).
≠ 1 so a ratio correction is necessary.
*)
of 0.1 (10 %) the measurement temperature
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