Equipment Room Design; 110-Type Hardware Equipment Room Applications; Trunk/Auxiliary Field - AT&T 75 Wiring Manual

The AT&T System 75—System Description (555-200-100) or AT&T System 75 XE—System
Description (555-201-200) provides equipment room specifications for temperature, humidity,
air purity, lighting levels, and grounding. They also provide information on the floor and
wall space required for the system equipment and associated peripheral equipment installed
in the equipment room. For completeness, some of the information contained in these
documents is repeated in this guide.

110-Type Hardware Equipment Room Applications

In the equipment room, the 110-type hardware is used for the cross-connect field which
consists of a Trunk/Auxiliary Field and a Distribution Field (port, auxiliary, and station).

Trunk/Auxiliary Field

The Trunk/Auxiliary Field contains three distinct cross-connect areas:
The green field receives the network interface leads through 25-pair cables and
cross-connects those leads to the purple or yellow fields. A single row of the 110-type
hardware can terminate twenty-four 1-pair, eight 3-pair, or twelve 2-pair trunks.
The purple field connects to the switch via WP-90929, List 1 or 3 concentrator cables.
Each 110 terminal block row can terminate twenty-four 1-pair, eight 3-pair, or twelve
2-pair trunks. The purple field can also connect to the switch via 25-pair cables with
each trunk circuit pack connecting to one 25-pair row of the 110 terminal block.
The yellow field connects all miscellaneous leads from the switch such as alarm
monitors, emergency transfer relay power, attendant console power, and INADS
(Initialization and Administration System) trunk. This field is also used for
emergency transfer wiring, AP (Applications Processor) alarms, paging equipment,
music sources, etc.
Figure 3-19 shows 300-pair terminal block arrangements for the system Trunk/Auxiliary
Field. A one 300-pair terminal block arrangement provides for a capacity of 96 three-pair
circuits and a two 300-pair terminal block arrangement provides for a capacity of 192 three-
pair circuits.
Figure 3-20 shows 900-pair terminal block arrangements for the Trunk/Auxiliary Field. A
one 900-pair terminal block arrangement provides for a capacity of 288 three-pair circuits
and a two 900-pair terminal block arrangement provides for a capacity of 576 three-pair
circuits.

EQUIPMENT ROOM DESIGN

110-TYPE HARDWARE
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