24 Installing the Cross-Connect Panel
Practice 450-1011-201
Digital Trunk Link Connections to the Cross-connect Panel
The Digital Trunk Link SRU is equipped with a rear connector that cables the SRU
to a DS1-compatible terminating or repeating device up to 228.6 m (750 ft) away.
This procedure assumes that the DS1-compatible device has already been installed
and that transmission limits have been appropriately engineered. The cable is
ordered in standard lengths not exceeding 228.6 m (750 ft) in length.
The customer has the option of customizing the cable in the field. If the cable is not
already prepared, use the CERTI-CRIMP Crimping tool to connectorize the 15-pin
connectors to the cables, as described in Part 16. A single cable must consist of two
twisted pairs (22 or 24 gauge), plus shield ground. (See Table 8-B for pin
designations for the Digital Trunk Link connector.)
Make the connections as follows:
(1) If the rear door of the cabinet is closed, open it to access the rear panels of the
SRUs. Check the wiring log and provisioning worksheets for the position of the
DTL SRUs. (Each SRU is identified by a label on its front panel and by the
product code on a label on the rear panel.)
(2) Locate the DS1 interface cable, which is typically shipped with the LANlink
cables separately from the DTL SRU.
(3) Push the 15-pin D-subminiature connector into the connector on the rear panel
of the DTL SRU. (See Figures 8-7 and 8-8.)
(4) Snug the two screws on the connector with a flat-blade screwdriver.
- CAUTION -
Do not overtighten the screws. If the screws are too tight, problems may be
encountered later if they are removed.
(5) Route the cable down the left side of the cabinet, as viewed from the rear, and
out the space below the rear door. Tie-wrap the cable to the cabinet frame for
dressage.
(6) Route the cable along the floor at the rear of the cabinet, then to a
DS1-compatible terminating device such as a DX-1 cross-connect panel or a
repeater, or route the cable directly to a DS1-compatible line interface at a host
PBX.
(7) Make the wire-wraps for the cable as appropriate using a wire-wrap tool.
(8) Set the 7-position DIP switch on the rear of the SRU to select one of the three
ranges of cable equalization. This range is selected according to the length of
the interface cable. (See Fig. 8-9 for switch settings.)
(9) Repeat this procedure for each of the DTL SRUs in the system.
Table 8-B
PIN DESIGNATIONS FOR DIGITAL TRUNK LINK CONNECTOR
PIN
DESIGNATION