User's Manual

Installation
25
AC Rack E1 Cabling 120 ohm
Access Concentrator Interface Panel
All cabling to the access concentrator connects to the interface panel. Slots 4,5 and 6 can be
used for 75ohm and 120ohm connections. Slots 7-14 is used for 120ohm connections each
slot will support up to 8 E1 connections.
Access Concentrator Interface Panel (1026 Board)
120 ohm Cabling Specification
In installations with 12Oohm cabling Double screened, 120Ohm, 8 twisted pairs. The overall
screen should be screened with a foil AND 90% coverage tinned copper braid is to be used
for interconnection between the AC shelf, the DDF and switch/channel bank.
a) E1 Cabling (CT Link)
From the site survey, confirm the location of the Digital Distribution Frame (DDF) if a DDF is
to be used or the CT links if the E1 feeds are fed direct to the equipment. The length of E1
feeds should not exceed 100 metres.
Note: This must be a SELV port of an EN 60950 approved product.
Run the E1 cables from the AC shelf to the allocated positions on the DDF. (8 Pairs per CTU
in normal working,up to 3 CTUs per shelf.).In partial equipped installations it may be
appropriate to run enough cables to cater for a complete rack of equipment. This reduces the
need to disturb original installation when adding additional equipment.
Feed the E1 cables through the top hole on the left hand side of rack side of the rack, and
down the channel at the side of the rack. Identify and label each cable at both ends as well as
the DDF/Backhaul positions. Terminate all cables with RJ45 plugs and fit adapter 303-1112-
900 (See RJ45 terminations below) or use D-type connectors (See D-type terminations
below) at the rack .Terminate as appropriate at the DDF.
b) E1 Cabling (Switch Link)
From the site survey, confirm the location of the Digital Distribution Frame (DDF) if a DDF is
to be used or the Switch if the E1 feeds are fed directs to the equipment. The length of E1
feeds should not exceed 250 metres.