BT Versatility
Installation and maintenance Manual
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
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
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.
Primary Rate ISDN
Network Module 1 Analogue lines 1 and 2 or the First Basic Rate ISDN Line
Network Module 2
Voice ModuleAnalogue lines 3 and 4 or the second Basic Rate ISDN
Line or the Internal ISDN S0 Circuit
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