Honeywell XNX-AM Series, Technical Manual

Page: 119 / 207

XNX Universal Transmitter
Maintenance 117
Warning: When servicing or replacing sensors, reduce the risk of ignition in hazardous
atmospheres by declassifying the area or disconnecting the equipment from the supply circuit
before opening the sensor enclosure. Keep the assembly tightly closed during operation.
Warning: Take care when handling sensors as they may contain corrosive solutions. Do not
tamper or in any way disassemble the sensor cell. Do not expose to temperatures outside the
recommended range. Do not expose the sensor to organic solvents or flammable liquids.
Warning:
At the end of their working lives, sensors must be disposed of in an environmentally
safe manner, in accordance with local waste management requirements and environmental
legislation. Alternatively, sensors may be securely packaged, clearly marked for
environmental disposal, and returned to Honeywell Analytics. Do not incinerate sensors as
they may emit toxic fumes.
Warning:
Verify all outputs, including display, after installation, after service events, and
periodically to ensure the safety and integrity of the system..
WARNING
!
Caution:
The following procedure must be followed carefully and performed only by suitably
trained personnel. A fault condition will be signaled by the sensor if it is removed with the unit
under power.
CAUTION
!
Note: If the power-on-self-test was skipped during maintenance activities, restart the
transmitter.
NOTE
!
MPD Sensor Cartridge Replacement
Using
Figure 225
as a guide, follow this procedure:
1. Verify that the label on the new sensor is the correct gas
type.
2. Remove power from the transmitter.
3. Unscrew the weatherproof cover (if equipped), loosen the
retainer locking screw, and unscrew the sensor retainer.
4. Remove the old sensor cartridge by pulling without
twisting.
5. Slide the replacement into the MPD body. Align the tab
with the alignment slot, then press the sensor cartridge
firmly to seat it into the body.
6. Refit the sensor retainer, tighten the locking screw, and
refit the weatherproof cover (if equipped).
7. Recalibrate the MPD sensor following the procedure in the
Calibration Procedure section.
Cell Alignment Slot
Sensor Cartridge
IR or Cat Bead
Sensor Retainer
and Locking Screw
Internal O-ring
(critical to performance times)
Figure 225. Removing the plug-in sensor