SRS Labs QMS 100 Series, User Manual

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2-8 Features and Operation
SRS QMS Gas Analyzer
Spec Scan Parameters menu button on the toolbar
Table 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.
The alarm control and level settings can be edited by either double- clicking on the Alarm text
of the desired table entry, or by clicking on the 'Alarm X' (where X is the channel number)
button for the appropriate table entry in the Table Parameters dialog box.
Select the Schedule command (Scan menu) to set the scan trigger timing and frequency. The
Table Traces may be edited by either double-clicking on the text directly (except for the Alarm
text), or by selecting the Traces command (Graph menu).
Important: 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 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 old data is saved in a history buffer for
review at any time. The gas masses, names, and parameters can be set using the Scan Parameters
command from the Scan menu.
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) 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 control view bar may be used to zoom, scroll and view all data, even if a scan in progress.
Note that the Table mode, P vs. T mode, and Annunciator modes share the same table scan