Stanford Research Systems RGA100, Operating Manual And Programming Reference

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8 Appendix C
SRS Residual Gas Analyzer
Figure 7 . The AnalogIO Display mode of the PPM100 (w/CM readings disabled) shows
the voltage levels at the analog I/O ports.
Use analog I/O ports as inputs to read voltages from vacuum system instruments such as capacitance
manometers, analog output third-party gauges, mass flow controllers, turbo pump controllers, etc.
Analog output levels can be programmed manually from the front panel, remotely through the computer
interface, or they can be linked to partial pressure readings for closed-loop control of gas composition.
Use analog I/O ports as outputs to control auxiliary vacuum equipment such as heaters, actuators, ion
sources, programmable logic controllers, dosing valves and throttle controllers.
Capacitance Manometer readings (CM1-4)
The PPM100 controller can display pressure as measured by standard capacitance manometers (CMs). Up
to four independent CM readings can be monitored simultaneously. Pressure readings are updated at
2 Hz. The PPM100 precisely measures the 0 to 10 VDC linear output signal from the CM to determine
pressure. Full-scale ranges up to 1000 Torr are supported by the controller.
For added convenience, the PPM100 also supplies an auxiliary (AUX) ±15 V, 100 mA power output.
This is usually sufficient to power up a couple of standard (i.e. non-heated) capacitance manometers.
Tip! The CM pressure display mode can also be applied to display pressures from third-party vacuum
gauges with analog outputs linked to the log of the total pressure.
Data Logging (Charts and Tables)
All PPM100 controllers include Data Logging capabilities. When Data Logging is enabled, data from all
partial pressure measurements and all analog inputs are stored in a circular memory buffer at the rate
specified by a user-programmable logging interval.