Ametek WDG-V UOP, Руководство пользователя

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PN 9000-280-VE, Rev B
Calibration/Aspirator Air Setup Checks
If performing a manual calibration, wait for the reading to stabilize on
the display before switching to the next calibration gas.
Possible Cause Corrective Action
Calibration Gas Check To check calibration gas values:
From the
Calibration Gas Values
screen (AMEVision User Inter-
face), check the Calibration gas values entered to ensure they
match the analyzed concentration of the cylinders.
• Check that the correct calibration gas values have been en-
tered into the analyzer.
• Check that the calibration gas cylinders are turned on and are
not empty.
• Check for the proper flow rate and proper delivery pressure of
calibration gases when the remote calibration unit has been
activated (see the Inject Gas Diagnostic option in the AMEVision
Display User Interface Installation and User Manual for more
information.).
Calibration Line Check The best calibration gas to use for this check is an O
2
zero calibra-
tion gas.
Ensure that your calibration line is not contaminated with such
things as pipe dope, cutting fluid, oil, or solvents. All these
contaminants produce hydrocarbon vapors that interfere with
the proper calibration of your analyzer, resulting in lower than
expected oxygen readings. To test for contaminated lines, you
must temporarily bypass your current calibration line with a
clean calibration line (directly from cylinder to the analyzer cali-
bration inlet port, using a flow meter to set the proper flow) and
compare the response with that from the possibly contaminated
line.
Remote Calibration Unit
(RCU) Problem
The RCU contains one normally open solenoid-the aspirator air
solenoid. All other solenoids are normally closed. Problems with
the RCU are usually as follows:
Plumbing Leak:
To check for plumbing leaks, disconnect power from the RCU
and pressurize the inlets. Apply a leak detecting liquid along the
base of the solenoids and any plumbing fittings. Repair any leaks
found.
Solenoid Not Energizing:
The solenoid drive signal is a 12 VDC signal. This is used to close
the aspirator solenoid and open the appropriate calibration gas
solenoid. To test a solenoid valve, select
Inject Cal Gas
from the
Calibrate menu to energize that solenoid. Verify that the sole-
noid drive signal is present. The aspirator air solenoid is closed
when the drive signal is applied. Other solenoids are open when
the drive signal is applied (Cal Gas flowing). With the drive signal
present, verify the proper flow. If no signal is present, check the
interconnecting wiring between the control unit and the RCU.
If wiring is correct, replace the
Sensor
board. If the solenoid
drive signal is present, it indicates a problem with one of the
solenoid valves. Replace the solenoid valve, being sure that the
solenoid o-ring seals are properly positioned.

Calibration

Cal Gas
Values
Maintenance and Troubleshooting
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