Instruction Manual

Model CXT-IR
2.2 Sensor Placement
Selection of sensor location is critical to the overall safe performance of the product. Six factors play an
important role in selection of sensor locations:
• Density of the gas to be detected
• Most probable leak sources within the industrial process
• Ventilation or prevailing wind conditions
• Personnel exposure
• Placement of transmitting antenna
• Maintenance access
Density
Placement of sensors relative to the density of the target gas should be located within 4 feet of grade as heavy
gases tend to settle in low lying areas. For gases lighter than air, sensor placement should be 4 to 8 feet above
grade in open areas or in pitched areas of enclosed spaces.
Leak Sources
The most probable leak sources within an industrial process include flanges, valves, and tubing connections of
the sealed type where seals may either fail or wear. Other leak sources are best determined by facility
engineers with experience in similar processes.
Ventilation
Normal ventilation or prevailing wind conditions can dictate efficient location of gas sensors in a manner
where the migration of gas clouds is quickly detected.
Personnel Exposure
The undetected migration of gas clouds should not be allowed to approach concentrated personnel areas such
as control rooms, maintenance or warehouse buildings. A more general and applicable sensor location is
combining leak source and perimeter protection in the best possible configuration.
Maintenance Access
Consideration should be given to providing easy access for maintenance personnel and the consequences of
close proximity to contaminants that may foul the sensor prematurely.
NOTE
In all installations the gas sensor should point straight down (Figure 11). Improper sensor
orientation may result in false readings and permanent sensor damage.
Placement of RF Antenna
Placement of the sensor should have consideration made for line of sight RF transmissions. The devices should
be placed in a reasonable proximity to other devices in the network. Obstacles between CXT transceivers can
impact RF line-of-sight and may result in communication problems. The CXT sensor should be in view of at
least one other transceiver.
Additional Placement Considerations
CXT-IR Instruction Manual Rev. 1.6 Page 9 of 44