SRS Labs QMS 100 Series, Руководство пользователя

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2-10 Features and Operation
SRS QMS Gas Analyzer
The Annunciator channels can be independently configured. Some channels can use the Channel
Electron Multiplier (CEM) while others can have different scan speed with the CEM off.
The alarm control and level settings can be edited by either double clicking on the Alarm text of
the desired Annunciator entry, or by clicking on the 'Alarm X' (where X is the channel number)
button for the Annunciator channel in the Table Parameters dialog box.
The Schedule command (Scan menu) may be used to set the scan trigger frequency.
The Annunciator display mode cannot be split with other modes.
Important:
Table mode, P vs. T mode, and Annunciator mode share the same table scan parameters, alarm
parameters, and graph trace colors.
In Annunciator mode each channel value (partial pressure) is acquired directly from the RGA
head by individually querying the partial pressure for the appropriate mass. This is done for all
the selected masses using the present scan schedule as a trigger.
Library (Mode Menu)
Library mode displays the selected library gas fragment patterns in a histogram graph. When
split with a histogram or analog graph, the mass range of the library will automatically match
that graph's range for easy comparison of gases. All library information is read from the
"gaslib.dat ASCII file located in the same directory as "rga.exe". This file may be edited (with a
text editor) to add, delete, or modify gases in the library. The exact library file format must be
preserved for proper operation of this mode.
The Library Traces (bars) colors my be changed by either double clicking on the bars directly or
by using the Traces command (Graph menu).
The library scan parameters (displayed mass range) may be changed using the Library
Parameters command in the Scan menu. The cursor tool (Utility menu) can be used for the
analog, histogram, PVST, leak and library modes.
Data Acquisition
The terms Data Acquisition and Scanning are used interchangeably in the SRS RGA
documentation. A scan implies that the SRS RGA Head is performing ion current readings and
sending the data over the RS232 cable to the PC running the RGA program at a fixed rate of
28.8 kBaud. This data is graphed using the currently active display mode chosen by the user. The
speed of graphing depends on the hardware used and can vary with types of CPUs, video cards,
Serial ports etc.
The main procedure for establishing a live scan is outlined below:
1. Turn on the SRS RGA Head.