Installation recommendations
Page 32
FP400 Product Guide
Deploying the sensor cable
The sensor cable is light weight at 34 kg (75 lb) per km so it can easily be deployed by running a
round shaft through the arbor holes in the cable reel and having 2 people walk along the fence line
laying cable as they go.
Once the cable is deployed, refer to the site plan and pull back and lay out sufficient sensor cable
to cover the site specific features (gates, bypasses, service loops, sensitivity loops).
The following factors must be considered when deploying sensor cable alongside the perimeter
fence:
•
the length of the section of sensor cable being deployed (lead-in cable, detecting cable)
•
clearance and access beside the fence
•
service loops, sensitivity loops, and gate coverage
•
site-specific features such as cable bypasses for gates and other structures on the perimeter
•
the location of start modules and end modules
Sensor cable splices
At all designated splice points, each section of sensor cable requires a service loop. The splice
point service loops allow the sensor cable and splice enclosure to be attached and removed from
the fence to make the splices. Splice point service loops also provide extra sensor cable for
making future repairs (if required). Inside the enclosure, the 2 sensor fibers must be fusion spliced.
Other fibers passing through the enclosure can be left intact (expressed fibers). Midspan access
techniques can be used at most splice points, depending on the configuration of the sensor zones.
When dressing the bare fibers, ensure that the bend radius is kept above a minimum bend radius
of 32 mm (1.25 in.) at all times. Any tighter bend radius may lead to optical fiber damage and
increased loss. Once the splices are complete and the sensor cable is attached to the fence, a
visual fault locater (VFL) should be used to verify the continuity of each spliced fiber.
Illustrated installation requirements
Using UV-resistant cable ties, attach the cable to the fence fabric either on a single wire at the
midpoint of the chain-link; or at the junction of two fence wires. Both methods work well, however
only one method should be used at an installation. Install the cable ties by hand, tightening them
enough to hold the cable snuggly against the fence fabric. The recommended cable tie spacing is
30 cm (1 ft.). The maximum recommended spacing is 45 cm (1.5 ft.). Once the cable is fully
installed, cut off and dispose of the cable tie tails.
Note
Install the sensor cable on the secure side of the perimeter (the opposite
side of the fence to the threat).
CAUTION
Do not use a mechanical device to tighten the cable ties. Over
tightening cable ties can compromise detection and operation.