MKS Granville-Phillips Mini-Convectron 275 series, Инструкция по эксплуатации

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Chapter 2
18
Mini-Convectron Module with RS-485
Instruction Manual - 275545
2.4 Important Precautions for
Mini-Convectron
Installation
The following precautions in the use and installation of the
Mini-Convectron must be observed.
• It is recommended that the Mini-Convectron be installed with the port
oriented vertically downward to ensure that no system condensates or
other liquids collect in the gauge tube. The gauge tube axis must be
horizontal if it is to be used at pressures above 1 Torr. Although the gauge
tube will read correctly below 1 Torr when mounted in any position,
erroneous readings will result at pressures above 1 Torr if the tube axis is
not horizontal.
• Do not use a compression mount (quick connect) for attaching the
Mini-Convectron to the system in applications resulting in positive
pressures in the gauge tube, Positive pressures might blow the tube out of
a compression fitting and damage equipment and injure personnel. Pipe
thread or flange mounting systems should be used for positive pressure
applications. In any case, the absolute pressure in the tube should not
exceed 1000 Torr.
• Do not perform electrical continuity tests on the Mini-Convectron tube
with instruments applying voltages in excess of 1 volt when the tube is at
vacuum, or 5 volts when at atmospheric pressure. Exceeding these
voltages will damage the sensing element.
• Keep the tube clean. Do not remove the mounting port cover until you
are ready to install the tube.
• Do not mount the Mini-Convectron in a manner such that deposition of
process vapors, upon the internal surfaces of the gauge tube, may occur
through line-of-sight access to the interior of the gauge tube.
• Do not install the Mini-Convectron where high amplitudes of vibration
are present. Excessive vibration will cause forced convection at high
pressure giving erroneous readings.
• Do not bake the Mini-Convectron at temperatures exceeding 85 °C.
• Do not install the gauge tubes where they will be subject to corrosive
gases such as mercury vapor or fluorine which will attack the gold plated
sensor.
• For greatest accuracy and repeatability the Mini-Convectron tube should
be located in a stable room temperature environment.
• All connections to the unit are to be made with shielded cable or cables.
The shield or shields are to be connected to the connector shell.