ATT System 25 Reference Manual

HARDWARE DESCRIPTION
Optional Power Equipment
In addition to the power supplies already mentioned, the following equipment can be used
with System 25.
Uninterruptible Power Supply
The AT&T 1KVA Uninterruptible Power Supply (UPS) Model 010U111 PEC 2403-004 is
recommended. At maximum load the UPS will bridge a 5-minute power outage. The UPS
must be connected to the common System 25 power outlet. One UPS will support a 2-
cabinet system.
AC Power Line Surge Suppressor
The TII Model 428 Self-Restoring Power...

HARDWARE DESCRIPTION
Connectivity
System 25 requires 4-pair building wiring that conforms to AT&T Premises Distribution
System (PDS) specifications.Various cords, cables, adapters, and connecting blocks are
used to facilitate the connection of equipment and associated cable and wire.
Major points of connectivity include the following:
l The system cross-connect field located on a wall adjacent to the system cabinets.
The field provides mounting space for the Trunk Access Equipment (TAE), Station...

HARDWARE DESCRIPTION
LEGEND:
A -
B -
C -
OPS -
SIP -D -
E -
F -
* -
SINGLE-ENDED 25-PAIR CONNECTOR CABLE (A25D)*
3 TO 1 SPLITTER CONNECTORIZED CABLE - PEC 2720-06X
2 TO 1 SPLITTER CONNECTORIZED CABLE - PEC 2720-05X
OFF-PREMISES STATION
STATION INTERCONNECT PANEL*
OCTOPUS CABLE - PEC 2720-05P
INSIDE WIRE*TRUNK ACCESS EQUIPMENT (TAE) CONNECTOR BLOCK*
FURNISHED BY INSTALLER
Figure 4-24.
Trunk Access Equipment (TAE) Connections
4-63 

HARDWARE DESCRIPTION
Station Interconnect Panel (SIP)
The Station Interconnect Panel (SIP) provides for the connection of the terminals (voice and
data), peripheral equipment, and some auxiliary equipment of the system to station port CPS.
This equipment includes voice terminals, attendant consoles, data terminals, System
Administration Terminal, Digital Tape Unit, and Call Accounting System. The SIP is made up
of 617A Panels and associated adapters.
617A Panel
The 617A Panel (Figure 4-25) is a metal...

HARDWARE DESCRIPTION
Figure 4-25. 617A Panel
4-65 

HARDWARE DESCRIPTION
Figure 4-26 shows voice terminal connections to the system cabinets via the SIP. Typically,
voice terminals are plugged into modular wall jacks that provide a cut-down block for building
wiring. At the SIP, 858A Adapters provide a cut-down point for 4-pair wire runs. An octopus
cable (PEC 2720-05P) from a station CP provides 25-pair connectorized cabling to eight 4-
pair modular jacks.Each jack is terminated on the SIP by an 858A Adapter. An octopus
cable connects a maximum of eight...

HARDWARE DESCRIPTION
Connectivity Figures
Figures 4-27 through 4-37 provide connection information for various equipment. These
figures have been included as an aid to understanding how equipment can be connected to
System 25 and to indicate required connecting and supporting equipment. Other
arrangements are possible; these figures can be useful in developing connecting
arrangements for new or customer-provided equipment.
The PEC codes have been noted on the figures, as have indications of the source...

HARDWARE DESCRIPTION
ADU Connections
Figures 4-34 and 4-35 provide connection information for data terminals and associated
single-line or multiline voice terminals.The voice terminal and data terminal leads are
separated at the SIP with a Y-adapter and are connected to their respective station ports.
Figure 4-36 presents a typical Multiple Asynchronous Data Unit (MADU) connection.
Figure 4-37 shows local power connections for Z3A1, Z3A2, and Z3A4 ADUs.
Auxiliary Equipment Connections
Diagrams for...

HARDWARE DESCRIPTION
SYSTEM 25PART OF
CABINETOCTOPUS
CABLE
PART OF
SIP
TN742C2ANALOGSIPW1D1
LINE CPADAPT.
EXPOSEDCABLE
D1
W1
SINGLE-LINE
VOICE
TERMINAL(NOTE)
C5
B1
LEGEND:B1- TYPICAL -103A CONNECTING BLOCK*
C2 - OCTOPUS CABLE (WP90780)
C5 - MODULAR CORD (D4BU-87) - FURNISHED WITH SET
D1- STANDARD GAS TUBE/FUSE PROTECTION PER AT&T PRACTICE 46O-1OO-4OO*G- APPROVED BUILDING GROUND
W1- 4-PAIR INSIDE WIRING CABLE*
NOTE:MAXIMUM LOOP RESISTANCE FROM SYSTEM CABINET 

HARDWARE DESCRIPTION
PART OF TAE
SYSTEM 25PART OF700A NETWORK
CABINET
OCTOPUSINTERFACE BLOCKCABLE(110- OR 66-TYPE)
PART OFNETWORK
SIPINTERFACE
TN742
C2SIPW1AANALOGRJ21XADAPT.LINE CP
OPS
SINGLE-LINECENTRAL
VOICE TERMINALOFFICE
LEGEND:
A -SINGLE-ENDED 25 PAIR CABLE (A25D)*
C2 -OCTOPUS CABLE (WP90780) - PEC 2720-05P
W1 -4 PAIR INSIDE WIRING CABLE*
* -FURNISHED BY INSTALLER
Figure 4-29.Off-Premises Station Single-Line Voice Terminal Connections
4-70