Designing The Mdf For A Raised Floor - Avaya 6424D+M User Manual

7-24
MDF/lDF DESIGN: DEFINITY GENERIC 2 WITH UNIVERSAL MODULES
Use cross-connect hardware without connectors (for field terminations) for distribution cables.
Use cross-connect hardware without connectors (for field terminations) for equipment cables for
systems over five modules.
Use cross-connect hardware with connectors for equipment cables for systems of one to five
modules.
NOTE: The connector gender of the unshielded B25A cables supplied with Generic 2 universal
modules is male-to-female (M-F) with the male end connecting to the switch. To connect Generic 2
universal modules to a wall-field with female plugs already installed, use the A25D male-to-male (M-M)
connector.
If connector-type cross-connect hardware is used for connecting equipment cables, make sure that you
order the correct hardware.
Synchronization Clock
The synchronization clock provides enhanced network synchronization and improved transmission
performance in digital networks.
The clock can be connected to either duplicated or unduplicated systems. An unduplicated module or
TMS requires wall field space for 125 pair (5 cables) in consecutive blocks; a duplicated module or
TMS requires space for 150 pair (6 cables) in consecutive blocks.
The clock should be connected to the auxiliary equipment and miscellaneous field, that is, the yellow
portion of the wall field. There are three ways to establish the yellow wall-field cross connection. In
order of preference they are as follows:
Yellow field—Use a portion of this field that has not been dedicated to other equipment.
Spare field—Convert spare field space to a yellow field dedicated to the clock.
Custom installation—As a last resort, install a 110A-300 block dedicated to the clock on or near the
MDF.

DESIGNING THE MDF FOR A RAISED FLOOR

A modem communications system is perceived by the customer to look like a computer installation.
For this reason, some customers request that the communications systems installed in the equipment
rooms be installed on raised flooring to conceal unsightly cabling and over-the-cabinet racks or ducts.
Also, where communications systems are installed beside computer installations, the communications
systems wiring must conform to the computer's installation wiring, which must be out of sight.
Using the raised-floor design may make installation time longer for systems of two modules or more and
the same amount of time for single-module systems. Changes and additions also may take more time
than the normal installations if cabling is involved. Several factors contribute to the increased time:
some are logistical (such as removing tiles), some are engineering (such as detail design or structural
considerations for frame mounting), and some relate to the installation of cables (such as storage of
cable slack or dressing of cables via holes in the floor).