Ametek ASR900, Installation And Maintenance Manual

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Maintenance | 4-5
2. If the analyzer uses measured Pressure Compensation (optional),
change the pressure compensation to fixed mode so that a “ f: Sample
gas pressure too low ” alarm does not occur. To do this, view the Cell/
Misc Parameters dialog box and enter a value in the Default Cell
Pres (pressure compensation) field that is the same as, or approxi-
mately, the Measuring Cell pressure. Refer to “Cell/Miscellaneous
(Compensation) Parameters” in Chapter 4.
Close the isolation valve on the Sample Probe. Backpurge the analyzer
sample system with Zero gas for 2–3 minutes.
3. Change the Flow Control setting to ‘ 1 ’ ( shut-in/off ). Click Apply (next
to Flow Control ) and then click OK .
Bleed down the sample system to atmospheric pressure (check gauge).
Close the valve on the Vent Line side.
4. Disconnect AC power to the analyzer and power down the computer
before performing maintenance on the analyzer.
Hazardous Locations
Always disconnect mains AC power and/or alternate power sources
to the analyzer before opening any covers or doors on the analyzer to
check or perform maintenance on any components within the enclo-
sures.
If it is necessary to open the analyzer’s covers or doors while the
circuits are live, test the area for flammable gases (and proceed only
when the area is safe). To work on the analyzer with it powered up
and its electronics enclosure(s) open, take appropriate precautions to
avoid electrical shock. Hazardous voltages are present inside.
!
WARNING

See Fuse Legend
inside analyzer’s Lower
Enclosure.