The Primary Rate Interface Module
80-14005000-01
2–1
2
The Primary Rate Interface Module
2.1 Introduction
The Primary Rate Interface Module (SBUPRI) works in conjunction with
the other modules in the Backup system and ‘standalone’ operation is
not possible. The SBUPRI provides up to 30 ISDN ‘B’ channels (23 for
USA) for use by other application cards in the system.
Management is provided via the Shelf Manager Module.
Access to the cards in the shelf is by password which is entered on the
first poll of the shelf. Alarm messages from the cards in the shelf are
routed to the alarm and/or command ports on the Shelf Manager
Module.
The front card carries out the call processing functions, the rear card
carries the line matching/isolating transformers. Both front and rear
cards are not interchangeable between the CBUPRI/E1 and SBUPRI-
23/30 modules.
2.2 Front and Rear cards
The panel layouts for the front and rear cards that make up the SBUPRI
are shown in
Figure 1
overleaf. The ‘Master’ LED is labelled ‘Talkwire’
on the earlier PRIM, but the function is not implemented.
