AO2000-LS25
LASER ANALYZERS | OI/AO2000-LS25-EN REV. D
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Peltier pump (A):
The current drawn by the Peltier element.
Modulation ampl. (V):
Amplitude of the high frequency modulation voltage to the laser.
TU/RU temp.:
The temperatures measured by the embedded thermistors
located inside the transmitter and receiver units.
Extra current input (mA):
Current measured at the analog input (flow 4 to 20 mA input).
Air pressure (Bar):
The ambient pressure measured by the embedded pressure
sensor located inside the transmitter unit.
<Plot readings>
<Plot readings> plots the measured average and instant
concentration of gases, transmission and spectral temperature
(if measured).
Two different plots can be shown simultaneously. Clicking on the
axis labels modifies the scale of the plot.
Second harmonic signal <Second harmonic signal>
<Second harmonic signal> displays signals recorded by the
device for calculation of the gas concentration.
Yellow: 2. Harmonics filtered
Pink: 2. Harmonics detected
Figure 37: Menu Second harmonic signal (example)
This signal is also useful for inspection and analysis of the
absorption spectra, verification of proper laser function, and
fault diagnostics.
In total three curves are displayed: the normalized second
harmonic signal as detected (pink curve) and the same signal
after filtering with two different filters (yellow and blue curves).
For some instruments only one filter is applied to the signal.
The example given in Figure 37 displays the signal from an
oxygen absorption line.
The peak of the yellow curve is marked with a red cross.
The current gas concentration measured according to this line,
the sample number and the position of the peak are displayed at
the top right of the diagram.
The latter are also referred to as “Line position” and “Line
amplitude” and are described in
