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

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Maintenance
Mini-Convectron Module with RS-485
49
Instruction Manual - 275545
Saf
e
ty Ins
tructions
Introduction
Installatio
n
O
p
e
ra
tion
M
a
inten
ance
Calibration
The fumes from solvents can be dangerous to your
health if inhaled and they should be used in
well−ventilated areas exhausted to the outdoors.
Acetone and toluene are highly flammable and
should be used away from open flame or electrical
equipment.
Table 5-1 General Symptoms/Possible Causes (continued)
Symptom Possible causes
Readout cannot be calibrated to the
specified value using TS or TZ
commands 1. Gauge tube contaminated with material from vacuum system. Clean gauge
tube. If not effective, replace gauge tube.
Cleaning:
Prior to cleaning, the gauge tube must be removed from the electronics as
described on page 47. Cleaning solvents can damage electronic components or
the enclosure.
When the small sensor wire is contaminated with oil or other films, its emissivity
or its diameter may be appreciably altered and a change of calibration will result.
Cleaning with trichloroethylene, perchloroethylene, toluene, or acetone is
possible but it must be done very carefully so as not to damage the sensor.
a. Hold the gauge with the main body horizontal and the port projecting upward
at a 45° angle.
b. Slowly fill the port with solvent using a standard wash bottle with the spout
inserted in the port to the point where it touches the screen. Let the solvent
stand in the gauge for at least ten minutes.
Do not shake the gauge. Shaking the
gauge with liquid inside can damage the sensor wire.
c. To drain the gauge, position it horizontally with the port facing downward.
d. Allow the gauge to dry overnight with the port vertically downward and
uncapped. Before re-installing the gauge on the system, be certain no solvent
odor remains.
2. The gold plating on sensor has been attacked by a gas such as fluorine or
mercury vapor, changing its emissivity and/or resistance. Replace the gauge
tube. Cleaning cannot solve this problem.
Readout indicating a pressure in
system vastly different than being
observed by supporting gauges Gas composition on system not what user believes it to be. This can be caused by
selective gas pumping, process in use, outgassing of product, etc. Determine gas
composition and calibrate accordingly.