Stanford Research Systems RGA100, Operating Manual And Programming Reference

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Features and Operation 5-9
SRS Residual Gas Analyzer
The data acquisition method for the table scan will vary depending on the display mode
selected:
In Table mode or Table mode split with P vs T mode, each table entry 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. The time to
acquire each partial pressure depends on the scan speed selected for that
mass (the plotting speed depends on the user's computer).
In Table mode split with Analog or Histogram mode, the Table entry values
are extracted from the Analog or Histogram spectrum. No individual
mass query is performed. If a Table mass lies outside the Analog or
Histogram mass range, its partial pressure will show a zero value with the
alarm indicating the appropriate zero value warning. A table entry can be
easily disabled using the Table Parameters dialog box.
P vs T (Mode Menu )
Pressure versus Time mode is a scroll graph of up to ten gas masses in the same plot.
The graph scrolls to the left as the data fills the screen and the data is saved for review at
any time. The gas masses, names, and parameters can be set using the Scan
Parameters… command from the Scan menu or the shortcut button of the Parameter
.
P vs T entries can be configured independently from each other. Some entries can use
the Channel Electron Multiplier (CEM) while others can have different scan speeds with
the CEM off. When this mode is split with Table mode, the result is a wealth of
information on the selected gases behavior. The Schedule command (Scan menu) or
the shortcut button of the clock figure
may be used to set the scan trigger timing and
frequency. The P vs T Traces may be edited by either double clicking on them directly,
or by selecting the Traces menu.
The ViewControl Bar ( ) may be used to zoom, scroll, and view
all the data in the history buffers. While in this history mode, the RGA can still be
scanning new data without scrolling the graph.
Note that the Table mode, P vs T mode, and Annunciator mode share the same table scan
parameters, alarm parameters, and graph trace colors.
The data acquisition method for the P vs T scan will vary depending on the display mode
selected:
In P vs T mode or Table mode split with P vs T mode, each table entry 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.
In P vs T mode split with Analog or Histogram mode, the P vs T entry
values are extracted from the Analog or Histogram spectrum. No