AT&T 75 Wiring Manual page 150

Z100-TYPE HARDWARE
Requirements—Optional DID Make-Busy Trunk
Figures 2-90 shows the connections at the cable access panel for an optional Direct Inward
Dialing (DID) make-busy trunk. This option prevents DID trunks from being taken out of
service by the serving central office during emergency transfer. This trunk is used for this
function only and should be specified to appear on the twenty-fifth pair of a network
interface jack.
Installation—Terminals
Cable Access Panel Connections— Terminals Used Only for Emergency Failure Transfer
1 . At first cable access panel, run and connect pair of wires between PWR terminals
on EM XR terminal row to EM TRANS POWER terminal (see Figure 2-88).
2 .
Remove T and R straps for each central office (CO) trunk to be used for emergency
transfer.
3 .
Run and connect CO trunk circuit leads on CABINET CABLES side to TC
terminals on EM XR terminal row for each trunk.
Run and connect CO trunk circuit leads on DISTRIBUTION CABLES side to TK
4 .
terminals on EM XR terminal row for each trunk.
5 . Connect terminal leads on X connector (see Note) to ST terminals on EM XR
terminal row for each emergency transfer terminal.
Note: Terminal leads appear on pairs 1, 4, 7, 10, 13, 16, 19, or 22 (the first
pair of any 3-pair group).
6 . If more emergency transfer only terminals are to be installed, run and connect two
wires from PWR terminals on next cable access panel to EM TRANS POWER
terminals on first cable access panel and repeat from step 2.
2-124