Avaya 6424D+M User Manual page 36

MDF/lDF DESIGN: SYSTEM 85 AND DEFINITY GENERIC 2 WITH TRADITIONAL MODULES
NOTE: When a blue field is used, the blue field cross-connects directly to the purple field and not to
the white field.
Terminate only six 4-pair DIW cables to each index strip of a 110AB1-300 wiring block (the 25th pair
is unused), which means that you can terminate a maximum of 72 four-pair DIW cables on each 300-
pair wiring block.
Although the termination of 72 four-pair DIW cables leaves 12 unused pairs, you must add an additional
block to terminate more pairs. For example, to terminate 75 four-pair DIW cables, you would use two
blocks instead of one.
Constructing the MDF
Once you have calculated the number of cable pairs needed for each of the MDF areas and converted
them to the number of 300-pair blocks needed, decide the following:
Where to locate the MDF
How to mount the terminal blocks
How to arrange the terminal blocks
How to connect to the terminal blocks
Locating the MDF
Locate MDF as close to the switch cabinets as possible. The preferred location is in the equipment
room, but if space is not available, locate it in a separate area within 20 to 30 ft of the equipment room.
Orient the MDF so that the distribution cables can be routed to it as directly as possible.
Mounting the Terminal Blocks
You can mount the MDF hardware in one of the following three ways:
Directly to a wall
On a wall-mounted frame
On a self-supported frame
Use the table 2-4, Mounting Methods, which suggests which method to use for a given number of
modules, as a mounting guide for System 85 and DEFINITY Generic 2 with traditional modules. But
remember that the space available for the MDF may affect your decision.
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