Install Telecommunications Cabling
MDF Cross-Connect Fields
406
SI Installation and Upgrades
June 2004
Figure 136: Example MDF Connections (MCC1-Multicarrier Cabinet)
MDF Cross-Connect Fields
Each Main Distribution Frame (MDF) contains a trunk/auxiliary field and a distribution field. The
trunk/auxiliary field contains three cross-connect areas:
•
The green field terminates the network interface leads from the Central Office (CO) and provides
the terminals to cross-connect the leads to the purple or yellow fields as required. A single row of
the 110-type terminal block can terminate twenty-four 1-pair, eight 3-pair, or twelve 2-pair trunks.
•
The purple field terminates the trunk circuits from the system with
WP-90929, List 1 or 3 concentrator cables. Also, 25-pair cables can be used to terminate trunk
circuits from the system with each trunk circuit pack connecting to one 25-pair row of the 110-
type terminal block. Each terminal block row can terminate twenty-four 1-pair, eight 3-pair, or
twelve 2-pair trunks.
•
The yellow field provides cross-connect terminals for all miscellaneous leads from the system,
such as alarm monitors, emergency transfer relay power, and attendant console power. This field
is used for emergency transfer wiring, paging equipment, music sources, and so forth.
widfccf3 KLC 020802
4
1
10
19
4
13
22
2
11
20
5
14
23
3
12
21
6
15
24
9
18
7
16
25
8
17
Port Tie Trunk
4 Port Tie Trunk
w/ E&M Signaling
Port Data Line
8
Port Digital
8
Port BRI
12
Port Hybrid
8
Port DID
8
Port Analog
Port CO
8
8
1
10
19
4
13
22
2
11
20
5
14
23
3
12
21
6
15
24
9
18
7
16
25
8
17
Port Digital
24
24/32
16
Port Analog
Port Analog
16
24
Port Digital
Channel DS1
