Stanford Research Systems RGA100, Operating Manual And Programming Reference

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6-34 Ionizer Control Commands
SRS Residual Gas Analyzer
the filament is off, the new electron energy setting is stored in memory for the
next time the filament’’s emission is activated
Command excecution times vary depending on the pre-existing ionizer
conditions. The end of the command excecution is prompted to the host computer
by sending out the STATUS byte over RS232.
Note: The Electron Impact Ionization Energy is set to the default value when the
unit is turned on.
Important: The repeller grid and the focus plate are only biased while the
filament is emitting electrons.
Parameters:
EEparam, param: 25-105: The parameter represents the electron impact
ionization energy in eV.
EE* : The default Electron Energy value is used to run the command.
Default: 70 (eV)
EE?: Query. The electron energy parameter setting is returned over RS232 in
ASCII format.
Error checking:
Number parameters must be within the accepted range and must be integers.
The absence of a parameter (i. e. EE) is treated as a parameter-error.
FLparam, param: 0.00 - 3.50, *, ?
Description : Electron emission current (mA).
Echo : STATUS error byte or query response.
Set the electron emission current level in the ionizer. The parameter represents
the desired electron emission current in units of mA.
When a finite emission current is requested, the RGA biases the ionizer’’s repeller
grid and focus plate, and activates the filament’’s heater until the requested
electron current is established.
A null parameter value, turns off the filament and grounds the ionizer’’s repeller
grid and focus plate.
Command excecution times vary depending on the pre-existing ionizer
conditions. The end of the command excecution is prompted to the host computer
sending out the STATUS byte over RS232.
The Filament LED reflects the ionizer’’s emission status at all times.