MKS 275420-1-GQ-T-00011, Инструкция по эксплуатации

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Series 275 Convectron Module with DeviceNet
Instruction Manual - 275502 33
Warning - If used improperly, Convectron Gauges can supply misleading pressure
indications that can result in dangerous overpressure conditions within the system. For use
with gases other than air, or N
2
consult the gas type correction charts in Section 6.4.
Using the N
2
calibration to pressurize a vacuum system above about 1 Torr with certain
other gases can cause dangerously high pressures which may cause explosion of the
system. See Section 6.4 before using with other gases.
Calibration
6.1 Preparing for Pressure Measurement
The steps in this chapter assume:
•
The 275 Mini-Convectron was properly set up and installed per the instructions in Chapter 3.
•
The gas in your vacuum system is air or N
2
. If you are using other gases you must follow the
instructions in Section 6.4.
•
You are reasonably familiar with the general theory of operation of thermal conductivity gauges.
It is recommended that you consult a good textbook if you are unfamiliar with vacuum technology or
if you require more information on the general theory behind operating a thermal conductivity
gauge. The following books are useful reference volumes.
•
Dushman, S., Lafferty, J. M., Scientific Foundations Of Vacuum Technique, John Wiley & Sons, Inc.,
Second Edition, New York, 1962.
•
Redhead, P. A., et al., Ultrahigh Vacuum, Chapman and Hall, London, 1968.
•
O'Hanlon, J. F., A User’s Guide To Vacuum Technology, John Wiley & Sons, New York, 1980.
6.2 Gas Type
The Convectron gauge in the Mini-Convectron Module is calibrated for N
2
unless otherwise labeled
for custom applications.
6.3 Preparing For Convectron Gauge Operation
Install pressure limiting devices calibrated to a level that the vacuum system can safely withstand. In
addition, install pressure relief valves or rupture disks that will release pressure at a level considerably
below the maximum safe pressure level of the system.
Suppliers of pressure relief valves and pressure relief disks are listed in the Thomas Register under
“Valves, Relief,” and “Discs, Rupture.” Confirm that these safety devices are properly installed before
installing the Series 375 Convectron System. In addition, check that (1) the proper gas cylinders are
installed, (2) gas cylinder valve positions are correct on manual systems, and (3) the automation
settings are correct on automated gas delivery systems.
NOTE: Vacuum gauges with compression fittings may be forcefully ejected if the
vacuum system is pressurized.
Chapter 6