Det-Tronics PW9200x Pathwatch IR Gas Detection System User Manual
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To remove:
1.
Release the ribbon connector that connects the
AGC/TE cooler board to the preamplifier board,
which is permanently attached to the bottom of
the heat sink.
2.
Holding the ribbon connector to the side, pull the
AGC/TE cooler board so that the connector to the
motorbox disengages. Slide the board out of the
heat sink fins.
To replace:
1.
Position the board so that the two parts of the
connector to the motorbox are lined up.
2.
Holding the ribbon connector to the side, slide the
board into the fins of the heat sink as far as it will
go so that the connector to the motorbox
engages.
3.
Attach and lock the ribbon connector from the
preamplifier board.
DETECTOR/PREAMP ASSEMBLY
The detector/preamp assembly is comprised of the
infrared photodetector mounted inside a baffle, an
optical filter, the heat sink and the permanently
mounted preamplifier p.c. board. The detector/
preamp assembly is located on the top of the motor-
box beside the power supplies.
NOTE
Exposure to direct light (particularly fluorescent
light) can cause permanent damage to the
infrared photodetector. Care should be taken to
avoid exposing the photodetector to light when
the detector/preamp assembly is removed from
the instrument.
To remove:
1.
Remove the four 6-32 sockethead screws that
hold the assembly to the motorbox.
2.
Lift the assembly up until the baffle clears the
motorbox.
To replace:
1.
Position the assembly over the motorbox so that
the connector and hole for the baffle are aligned.
2.
Slide the assembly into place.
3.
Replace the four 6-32 sockethead screws that
hold the assembly to the motorbox.
SYNC PICKOFF
The sync pickoff is mounted in a socket, which is
located in the center of the rear panel p.c. board.
The sync pickoff is removed by pulling if from the
socket. To replace the sync pickoff, install with the
red dot up (toward the motorbox connectors).
SCHEDULED MAINTENANCE
It is recommended that the following maintenance
procedures be performed periodically as described:
Maintenance Procedure
Interval
12 mo. 24 mo.
Clean exterior optical components
X
Clean interior optical components
X
Replace filterwheel motor
X
Replace 15 watt lamp
X
Calibration check
X
Replace desiccant
X
CLEANING OF OPTICAL COMPONENTS
Exterior (12 month interval)
Due to the gradual accumulation of dust, chemical
deposits or other foreign matter, the exterior optical
surfaces must be cleaned every twelve months. In
some applications, cleaning of the windows may be
required more frequently. The need for cleaning can
usually be detected by a gradual decrease in the
NUMERATOR and DENOMINATOR output signals
and/or by visual inspection of the optical surfaces.
1.
Disconnect all power to the instrument.
NOTE
If possible, direct a flow of clean, oil-free com-
pressed air onto the optical surfaces before and
after cleaning.
2.
Clean the outer surfaces of the transmitter and
receiver windows with clean cotton swabs and
alcohol. Finish with clean optical tissue. DO NOT
TOUCH the windows or other optical surfaces
with bare hands.
3.
Reconnect the instrument and re-apply power.
Interior (24 month interval)
Interior optical components (inside surface of window,
lens, filters and sync pickoff) should be cleaned every
two years. Although it is possible to perform all these
procedures on-site, a lab environment is preferable
as it is cleaner and easier to work in. (See “Access to
Internal Components.”)
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