Granville-Phillips Series 330, Инструкция по эксплуатации

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5 Convectron Gauge Module
44
Series 330 Vacuum Gauge Controller
Instruction Manual - 330004 - Rev. 02
5.3 Convectron Operation
5.3.1 Reading Pressure
Pressure for the Convectron gauges is read only from the Analog Output connectors on the rear
panel of the 330 VGC.
5.3.2 Special Considerations For Use Below 10
-3
Torr
During a fast pumpdown from atmosphere, thermal effects will prevent the Convectron from
tracking pressure rapidly below 10
-3
Torr. After about 15 minutes, readings in the 10
-4
range will be
valid and response will be rapid. Calibration at vacuum may be performed at this time, or sooner if
readings in the 10
-4
range are not needed.
The 10
-4
Torr range is accurate to about 0.1 milliTorr provided the instrument has been carefully
zeroed at vacuum. See Section 5.3.6 on page 54 for vacuum and atmosphere calibration
procedures. For accurate use in the 10
-4
Torr range, zeroing should be repeated frequently.
Figure 5-4 Convectron Gauge Cables
If used without proper calibration or without reference to proper calibration tables,
Convectron gauges can supply misleading pressure indications. This may result in
dangerous overpressure conditions within the system. As supplied from the factory,
the controller is designed to read pressure for nitrogen. For use with any other gases,
consult the gas type correction charts found later in this chapter.