CommScope Trunk & Distribution Cable - Manual (Page 15)

Aerial Installation of CommScope Cable
There are two cable types built specifically for aerial installation:
QR/P3 JCA the standard construction, available in five sizes for trunk and feeder installation,
to be lashed to a strand or support wire, and
QR/P3 JCAM standard construction with a messenger extruded in place in a figure-8 design.
The two preferred methods for installation are the back-pull/stationary reel method and the drive-off/moving reel
method. Circumstances at the construction site and equipment/manpower availability will dictate which
placement method will be used.
The back-pull/stationary reel method is the usual method of cable
placement. The cable is run from the reel up to the strand, pulled by a block that only
travels forward and is held aloft by cable blocks. Cable is then cut and expansion
loops formed - lashing takes place after the cable is pulled.
The drive-off/moving reel method may realize some manpower and time
savings in cable placement and lash-up. In it, the cable is attached to the strand and
payed-off a reel moving away from it. The cable is lashed as it is being pulled - cuts
and expansion loops are made during lashing.
Regardless of the installation method, mechanical stress is of great concern during
cable placement. Like other coaxial cables, QR can be damaged by exceeding the maximum allowable pulling
tension or the minimum allowable bending radii. Fortunately, QR’s highly flexible construction permits lower than
normal pull tensions and tighter bends, almost completely eliminating the chance of cable installation
deformation.
Make sure all down guys at corners and dead ends are installed and tensioned prior to
cable placement.
QR cables
are particularly
resistant to
deformation in
cable geometry
during
installation
due to their
highly flexible
construction
Aerial Installation 3.1
Overview