Wiring Configurations
40
SafEye™
Toxic and Aromatic Open-Path Gas Detection System
6.2.3
Site Requirements
When selecting a site location and position for the SafEye system, the following
points must be considered:
•
Whether the gas being monitored is heavier or lighter than air
•
The individual site requirements
•
The detector should have a direct view of the source
•
The mounting point for each item should be secure and stable with minimal
vibrations
•
Equipment should be either mounted in a position where it cannot be knocked
out of alignment, or it is guarded from physical impact
6.2.4
The Source and Detector
The model of detector suitable should be selected according to the length of open
path to be monitored. To allow for ageing of the source, and a reduction of the
UV signal due to adverse weather, it is recommended to use a detector that is
not at the limit of its operating range.
The open path between the source and detector and the immediate surroundings
should be kept clear of obscuration that might hinder the free movement of air in
the protected area, or block the infrared beam.
6.2.5
Tips for Selecting a Gas Detector Location
The following are some tips for selecting gas detector locations, in order to
provide the best detection coverage:
•
For heavier-than-air gases: below potential leak sources.
•
For lighter-than-air gases: above potential leak sources.
•
Along the expected leak trajectory: near leak sources, considering prevailing
wind directions.
•
Between leak sources and potential ignition sources.
•
In areas with expected heavy fog, rain, snow, or extremely hot conditions,
consider the effects of long-range installation and install the detector at no
more than 80% from the maximum installation distance.
6.2.6
Wiring
•
For wiring, use color-coded conductors, suitable wire markings, or labels. The
wire cross-section must be between 1
–
2.5mm² / 18
–
14AWG.
•
The selected wire gauge should be based on the number of detectors used on
the same loop, and the distance from the control unit. The maximum number
of wire connections in a terminal is 2 wire cross-sections, each of 1mm².
•
To fully comply with EMC directive and protect against interference caused by
RFI and EMI, the cable to the detector must be shielded and the detector
must be grounded. The shield should be grounded at the detector end.