strength member. During pulling the cable pull line tension shall be
continuously monitored using dynamometers or load-cell instruments, and
shall not exceed the maximum tension specified by the cable
manufacturer. The mechanical stress placed upon the cable during
installation shall be such that the cable is not twisted or stretched.
A cable feeder guide shall be used between the cable reel and the face
of the duct or conduit to protect the cable and guide it into the duct
or conduit as it is unspooled from the reel. As the cable is unspooled
from the reel, it shall be inspected for jacket defects or damage. The
cable shall not be kinked or crushed and the minimum bend radius of the
cable shall not be exceeded during installation. Cable shall be hand
fed and guided through each manhole and additional lubricant shall be
applied at all intermediate manholes. When practicable, the center
pulling technique shall be used to lower pulling tension. That is, the
cable shall be pulled from the center point of the cable run towards
the end termination points. The method may require the cable to be
pulled in successive pulls. If the cable is pulled out of a junction
box or manhole the cable shall be protected from dirt and moisture by
laying the cable on a ground covering.
3.1.4
Service Loops
Each fiber optic cable shall have service loops of not less than 3 meters
9.8 feet in length at each end. The service loops shall be housed in a
service loop enclosure.
3.1.5
Metallic Sheath Grounding
**************************************************************************
NOTE: Direct burial cables with metallic sheath
will not be installed when transmission of
electromagnetic interference (EMI) or radio
frequency interference (RFI) through the metallic
sheath is a consideration.
**************************************************************************
Fiber optic cable with metallic sheath that enter buildings shall be
grounded at a point as close as practical to the building point of
entrance. Fiber optic cable with metallic sheath routed in the trench with
a power cable shall have the metallic sheath grounded at the cable
termination points.
3.1.6
Splices
**************************************************************************
NOTE: Maximum splice loss values per
ANSI/TIA/EIA-568B are 0.3 dB for fusion splices, and
0.3 dB for mechanical splices. These maximum loss
values are considered larger loss values than can be
provided by many manufacturers and installers. The
designer will specify lesser loss values when the
design and link loss budget require lesser values.
**************************************************************************
3.1.6.1
General
No splices will be permitted unless the length of cable being installed
exceeds the maximum standard cable length available from a manufacturer or
unless fiber optic pigtails are used to connect transmitters, receivers, or
SECTION 16768A
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