standards and guidelines for communication sites - Radio And ...

STANDARDS AND GUIDELINES FOR COMMUNICATION SITES EQUIPMENT CABLING
9.9.9.2 CABLING LACING REQUIREMENTS
When installing a system for telephone company or possibly other utility companies, special cabling
methods may be required. Observe the following considerations for the installation of telephone
company cabling:
• Lacing, rather than nylon cable ties, shall be used as the preferred means of cable attachment to
cable tray, to eliminate the possibility of sharp edges found on cut cable ties.
• The lacing method specified by the telephone company shall be used. Typical lacing is shown in
Figure 9-17.
FIGURE 9-17 TELEPHONE COMPANY LACING METHODS
• Lacing is typically 4- or 9-ply waxed polyester twine.
• Lacing of horizontal cables in cable trays should be performed every 914 mm (3 ft.).
• Lacing of vertical cables to a cable ladder should be performed at every rung of the cable ladder.
Any cable hanging between horizontal/vertical runways and racks cannot be unsupported for more
than 610 mm (24 in.).
9.9.10 DISTRIBUTION FRAME CONFIGURATIONS
A distribution frame (Figure 9-18 on page 9-30) provides a centralized cross-connection point for
audio, data, and alarm and control wiring between different pieces of equipment at a site and between
the site and external lines. Distribution frames shall be implemented using one of the following
methods:
• Distribution punch blocks affixed to a plywood panel that is mounted on a wall or a rack.
• Distribution punch blocks mounted on open-rack frames available from various manufacturers.
These frames can be anchored to the floor; they save wall space at the cost of floor space.
• Typically, a distributed (as opposed to centralized) method is used. Pre-wired cross-connect panels
(each 1 rack unit in height) distribute connections on a rack-by-rack basis. Typically, remote sites
require one panel and the prime site is equipped with one to three panels, depending on the
application.
68P81089E50-B 9/1/05 9-29