BT Versatility - Manual (Page 11)

BT Versatility
Installation and maintenance Manual
10
Modules located in the CCU
There are a number of modules that can be installed in the CCU.
• Analogue Line Module (Coloured Black). This provides 2 Analogue exchange lines. Up to two of these
modules can be installed in the CCU to provide two or four Analogue lines.
• Digital Line Module (Coloured Red). This card provides one ISDN 2 Basic Rate Interface. The same
module is used for the network T interface and the internal S-bus. Up to two of these modules can be
installed in the CCU providing one or two Basic Rate Interfaces.
There are two slots in the CCU for the Network modules. If required one slot can
be equipped with an Analogue module and the other with an ISDN Module.
• Voice module 2 or 4 port (Coloured Blue). Only one of these modules can be inserted in a unit.
• Primary Rate ISDN module (Coloured Yellow). This module provides for a Primary rate ISDN interface.
Up to 30 B-channels can be provided. (Availability TBC)
When a Primary Rate Interface is installed, the unit can be further equipped with
one or two Analogue modules or one or two ISDN Basic Rate modules to provide
backup in the event of the Primary Rate interface failing.
Module location
The Network, Voice and Primary Rate module locations in the CCU are indicated below.
Network Module 2
Analogue lines 3 and 4 or
the second Basic Rate ISDN
Line or the Internal ISDN S
0
Circuit
Voice Module
Primary Rate ISDN
Network Module 1
Analogue lines 1 and 2 or
the First Basic Rate ISDN
Line