PXML No. BABT/PXML/CRA.0020/0021/0022
APPROVAL No's. 210/220/230 - NS/3343/123/N/603533 / NS/3343/123/N/603532 /
NS/3343/123/N/603538
The PABXs are Electronic, Digital, Stored Programme Controlled employing Time Division
Multiplexing to establish connections and A Law Pulse Code Modulation for local voice
transmission.
The standard attendant equipment comprises an attendant's (Operator's) console, an
attendant interface card (ATTI) and an extension line card (PLCC). These cards are located
in the Peripheral Equipment Modules (PEM's).
In the event of power or major equipment failure, predetermined extensions are connected
to the Public network. The power fail extension telephones must be provided with Earth
recall to ensure continued operation after power fail. In the case of systems fitted with
DDI lines, these can be connected to a call answering machine in the by-pass emergency
mode.
The Omni range supported numerous type of attendant consoles. For information on early
consoles see NTX30.
The Omni 200 range only used the Level 3 console. This
was an enhanced Level 2 with a Disc Operating System
and greater on board memory.
OMNI 210
The system comprises a single cabinet and a TJF to which the cables from the PABX are
terminated. The cabinet contains a mains power supply, one or two ringing generators and a
shelf assembly (file) to house printed wiring cards. The file contains 36 card slots
allocated as follows:
10 slots for dedicated control cards
1 slot for power cards
2 slots for digital links
23 "Universal" slots
Universal slots can hold any peripheral card (e.g. Extension or CO)
OMNI 220
The system comprises a single cabinet and a TJF to which the cables from the PABX are
terminated. The cabinet contains a mains power supply, one or two ringing generators and
two shelf assemblies (files) to house printed wiring cards.
Each file contains 36 card slots allocated as follows:
10 slots for control cards
1 slot for power cards
slots for digital link cards
23 "Universal" slots
Universal slots can hold any peripheral card (e.g. Extension or CO)
OMNI 230
The system comprises one or two cabinets, depending on the number of lines required.
Additional cabinet(s) may be needed for housing batteries for back-up purposes. The system
is 48V powered and an external rectifier unit is needed.
Each equipment cabinet contains up to five shelf assemblies (files) to house printed
wiring cards. The files are referred to as Common Equipment Module (CEM) or Peripheral
Equipment Module (PEM). A CEM contains the control cards needed to run the system. A PEM
contains the peripheral cards (e.g. extension and trunk cards). A system normally contains
one CEM (SIMPLEX) but it is possible to have a second CEM as Standby in case of a failure
of the primary CEM (DUPLEX)
SYSTEM CAPACITIES
The maximum capacities for the OMNI 200 Series are as follows:
OMNI 210 OMNI 220
Extensions 256 512
Trunks * 92 184
Digital Links 2 4
OMNI 230
1 CEM/4 PEM 1 CEM/8 PEM
Extensions 1024 2048
Trunks * 512 1024
Digital Links 8 16
* Trunks include exchange lines DDI and Private Circuits.
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