Stanford Research Systems RGA100, Operating Manual And Programming Reference

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10 Appendix C
SRS Residual Gas Analyzer
Vacuum Process Control
Eight channels of process control are standard in the PPM100 controller.
Figure 9. Process Control Display mode of the PPM100. Eight process control channels
bring additional power and versatility to the PPM100.
Each channel has a relay closure output and corresponding opto-isolated TTL output signal, that may be
linked to a variety of input sources with intuitive user-programmable rules. Each individual channel can
be linked to any partial pressure or analog input, the system clock, gauge status or a TTL input trigger
signal. The Process Control module also includes several opto-isolated TTL level inputs, used to remotely
control filament on/off, degas on/off, E. MULT. On/Off, keypad lockout, datalogging reset and
touchscreen enable/disable functions.
Manual override is available for all process control channels, making it possible to manually control
channel relays and TTL output levels directly from the front panel. Manual relay control makes it possible
to use the PPM100 as a standalone controller capable of manually or automatically managing the
operation of any standard vacuum system.
All process control events are automatically time-stamped and recorded in memory (Event Logging) so
they can be reviewed at any time. Use the History button on the Process Control panel to access the
Process Control Event Log at any time.
Computer Interfaces (RS-232, GPIB and USB)
PPM100 includes standard RS-232, GPIB and USB communication ports. A host computer connected to
the instrument can easily configure, diagnose and operate the PPM100 controller using simple ASCII
commands. An intuitive and complete Remote Command Set facilitates integration of all controller
functions into any processing or diagnostic software. The same command set is shared by the RS232,
USB and GPIB interfaces.