Instruction manual

HARDWARE DESCRIPTION
HARDWARE DESCRIPTION
This Section provides descriptions of System 25 hardware components and their functions.
The hardware is covered under the following major headings:
● System Cabinets:
Includes circuit pack (CP) carriers, power supplies, wiring, and
cooling equipment.
● Circuit Packs: Includes detailed information on CPs.
● Terminal Equipment:
Equipment that can be connected to voice or data station
ports.
● Peripheral Equipment: Equipment that can be connected to the CPU/MEM CP.
● Auxiliary Equipment: Service- and feature-related supporting equipment.
● Connectivity: Equipment and arrangements for interconnecting the various elements
of System 25 hardware.
Note: Equipment that is directly associated with a specific feature or service
covered in Section 2 is also described there; such equipment is noted in this
Hardware Description section, with a reference to the appropriate heading in
Section 2.
All system hardware, except Cabinet 1 equipped with a CPU/MEM, Service Circuit, and
associated cables, is optional.
A listing of Product Element Codes (PECs), Apparatus Codes, and Comcodes is provided in
Section 7, “Parts Information.”
System Cabinets (J58901A1 L4)
The system can consist of one, two, or three cabinets (Figure 4-1). Each cabinet contains its
own power supply and cooling system.
A CP carrier frame is integrated into each cabinet.
Depending on the circuit pack complement, the cabinet/circuit pack configuration is as
follows:
● Cabinet 1 (always required)—Contains the CPU/MEM CP and the Service Circuit of
the system and can also contain up to ten port CPs.
● Cabinet 2 or 3 (optional)—
Provides mounting for up to 12 port CPs each.
The CPs receive power, control signals, and data via the backplane bus of the carrier and
associated 25-pair connector interfaces.
In multiple cabinet systems, the backplane buses
are linked with a bus extender cable (J58901A4 L3).
4-1