2 - 7
HAPSITE ER Operating Manual
The NEG pump can effectively remove active gases, but not noble gases. An ion
pump is necessary to pump out noble gases, which would accumulate in the Mass
Spectrometer. The accumulation would raise the Mass Spectrometer pressure and
interfere with operation.
The turbo molecular pump in the Service Module is actually a compound pump,
incorporating turbo molecular stages for high pumping speeds at low pressure, and
molecular drag stages to provide good compression of the gas at higher pressures.
However, even with drag stages, the turbo molecular pump is unable to exhaust
gas into atmospheric pressure. An additional diaphragm roughing pump is
provided for this purpose.
The diaphragm pump consists of four stages. The diaphragm pump draws the gas
from the exhaust of the compound pump and sufficiently compresses exhaust gas
in order to discharge the exhaust into the atmosphere.
2.4.4 Electronic Systems
The electronic systems in HAPSITE ER are considered in four groups:
Mass Spectrometer Control, see section 2.4.4.1
Gas Chromatograph Control, see section 2.4.4.2
Main Processor, see section 2.4.4.3
Interfaces, see section 2.4.4.4
2.4.4.1 Mass Spectrometer Control
The Mass Spectrometer control electronics include the programmable DC and RF
power supplies for the mass selector, DC power supplies for the filament, electron
multiplier, ion pump, and A/D converter for the signal from the electron multiplier.
2.4.4.2 Gas Chromatograph Control
The Gas Chromatograph (GC) control circuitry includes the power supplies for the
solenoid valves, ovens and heated inlet line. It also controls the logic for all the
valves and heaters of the GC system.
2.4.4.3 Main Processor
The main processor is supported by solid state memory and is located in the central
electronics assembly. The main processor controls all the other electronic
sub-assemblies for routine operation.
To Next Page
Loading...
