AO2000-LS25
LASER ANALYZERS | OI/AO2000-LS25-EN REV. D
53
Description of menus and parameters
Main menu
After pressing the <User mode> button the program opens the
“Measurements” menu. The example below is for a device
measuring oxygen.
Figure 36: Menu “Measurements” (example)
The serial number of the device is shown in the title line of the
menu. The bottom right of the screen shows different menus
which can be accessed either by pressing the buttons or by
pressing the underlined shortcut letters (e.g. <S> for Second
harmonic signal (Second harmonic signal)). By pressing <Exit
menu> one can always go back to the previous menu. The
description of each menu will follow.
The rest of the screen is used to display different readings
parameters. By default only the main readings parameters are
displayed. All parameters are displayed by pressing <Show extra
readings>.
Note
<Show extra readings> is activated in the above example.
The device readings update period is set by pressing <Screen
update period>, which is 5 seconds by default. This time should
not be shorter than the time required to calculate the
concentration (the update time of the LCD).
The parameters are explained in detail below:
Status:
The device status can be SLEEPMODE / STARTUP / OK /
WARNING / ERROR.
Refer to
Serial No.
Serial number of the analyzer.
Mode:
The measuring mode of the device. This is optional and only for
devices with zero / span check. 3 different measuring modes can
be selected by clicking the <Mode:> button.
Refer to
Note
Maintenance mode “Maintenance” is not available for the LS25.
Concentration Instant:
Displays
the last value calculated by the analyzer with no
averaging. This is in the following called a primary measurement.
Concentration Average:
Displays the running average calculated by the analyzer (not by
the service program) from the last N values, where N is the
averaging count specified in menu <Measurement
configuration>.
A description of the averaging method will be given in that
subsection.
Concentration Standard:
Gives an estimate of the running standard deviation also
calculated by the analyzer.
This number indicates how much the calculated gas
concentration fluctuates from its average value. If the gas
concentration is truly constant it will provide a measure of the
instrument precision.
Line width:
Relative measure of the width of the absorption line. In
combination with the line amplitude it determines the
integrated absorption, which in turn is used to calculate the gas
concentration.
The reference line width parameter is equal to 1.000 at T = 23 °C
and P= 1.013 bar (1 atm.) and when the gas composition is equal
to those used when calibrating the instrument.
The line width increases with gas pressure and decreases with
gas temperature. It also depends on the gas composition,
e.g. water vapor broadens the absorption lines significantly.
