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 Line Surge Suppressor (PEC 8310-001, Comcode
402988950) protects against electrical surges, spikes, and transients that can cause damage
to the System 25 power supply. A pilot light indicates that full protection is present. The unit
plugs directly into a standard 120-volt 15-amp grounded outlet, providing a dual outlet for
protected equipment.
346 Modular Bulk Power Supply
The 346 Modular Bulk Power Supply (346 MBPS) is a cost effective and flexible alternative to
the KS-22911 power supply. The 346 MBPS can be used where the wall outlet mounted
KS-22911 cannot be used (Canada) or where multiple KS units are required. The 346 MBPS
consists of the 346A Power Unit (346A PU) and the 346A1 Power Panel; that is the sole
method of mounting the power units.Up to three 346A PUs can be mounted per power
panel. Each PU is capable of powering 4 terminals with adjuncts, for a total of 12 terminals
per full MBPS. The 346 MBPS is intended to be installed in a closet and should be near the
terminals (within 260 feet). All connections are modular and are made with cords and
adapters at the 858A Adapter on the SIP. Terminals and Selector Consoles can be powered
by the 346 MBPS.
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							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
Interconnect Panels (SIPs), and Emergency Transfer Units (ETUs).
Refer to Section 5,“Environmental Requirements” for a typical System 25 layout
including cross-connect field and associated equipment layout.
l 25-pair connectors located on the rear of each system cabinet.
l Modular jacks located at each work station provide modular connections for
terminals and associated adjuncts and auxiliary equipment. These jacks are
connected by building wiring to the SIP. Several wiring options are described below
Wiring Options: There are three basic PECs under which building (station) wiring is ordered:
l PEC 2781-004 covers wiring done on an hourly rate.
l PEC 2782-004 covers flat rate wiring.
l PEC 2783-004 covers firm price quote
Consult the 2780 section of the Sales Manual for restrictions and requirements before
ordering.
Trunk Access Equipment (TAE)
The TAE (Figure 4-24) provides for the connection of communications facilities such as Tie,
OPS, Ground Start, Loop Start, and DID trunks to the trunk ports of the system. Up to three
trunk CPs (except Tie Trunk CPs) can be connected to a 3-way splitter cable (PEC 2720-06X)
that concentrates the CP interfaces into one 25-pair cable. Up to two Tie Trunk CPs can be
connected to a 2-way splitter cable (PEC 2720-05X) that concentrates the CP interfaces into
one 25-pair cable. Each splitter cable connects to an interface block at the TAE.
Cables are either cut down or plugged into the TAE blocks. The other end of the cables plug
into the telephone company provided network interfaces (RJ21X or RJ2GX). Trunks and tie
lines are cut down by the telephone company at the network interface.
700A or 157B Blocks are usually used for the TAE connections (furnished by the installer).
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							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
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							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 plate with keyslot holes on each side for mounting
on a backboard. Each 617A Panel can hold eight Z210A1 or 858A Adapters, each of which
can accommodate six connections to the port circuits in the cabinets. As many as five 617A
Panels can be required for a maximum size system.The adapters snap into prepunched
holes on the 617A Panels. (Reattached spacer buttons keep adapters from touching the
metal panels.)
The cable rings located at the top of the 617A Panel route the building wiring cables to the
adapters. Purse lock clips hold the building wiring cables in place. The white posts at the
bottom of the 617A Panel guide the wiring from the 50A Fanning Strip to each column of
adapters.
Preprinted boxes and numbers on the panel identify modular jacks for recordkeeping
purposes. Letters are marked on the boxes at the top of each column by the installer. The
letter (A-J) and the corresponding preprinted row number (1-24) identify the port jacks. For
example, A1 identifies the modular jack located in column A row 1.
Adapters
Adapters that mount on the panel connect the following:
l Building wire runs terminated in modular jacks, 25-pair connectors, or unterminated.
l Cables from the system cabinets terminated in modular jacks or 25-pair connectors.
The following adapters can be mounted on the 617A panel:
l Z210A—Six 4-pair modular jacks to six 4-pair modular jacks. One required per six
voice terminals. Connects to building wiring terminated in modular plugs.
l 858A—Six 4-pair modular jacks to six 110-type cut-down blocks. One required per
six voice terminals. Connects to unterminated building wiring.
The SIP equipment is furnished by the installer.
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							HARDWARE DESCRIPTION
Figure 4-25. 617A Panel
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							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 voice terminals to a port CP.
SYSTEM CABINET
STATIONC2(1)CIRCUITPACK(8)
UNTERMINATED4-PAIR
BUILDING
WIRE
MODULAR
JACKS
PART OF SIP
VOICE TERMINALS,
ADJUNCTS,
POWER UNITS
LEGEND:C2 - OCTOPUS CABLE - PEC 2720-05P
858A ADAPTER (FURNISHED BY INSTALLER) -
SIX 4-PAIR MODULAR JACKS TO
SIX 110-TYPE CUTDOWN BLOCKS
Figure 4-26.Typical SIP Connections
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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 for
obtaining non-PEC equipment (for example, from installer or furnished with other equipment).
This information can be of use to Account Executives and Technical Consultants who are
adding equipment to existing installations. For new installations, the DOSS Configurator must
be used to select equipment requirements.For existing installations, you will need to
determine what equipment is already installed. You should not order equipment directly using
the PECs in these figures.The octopus cable (PEC 2720-05P), for example, supports eight
terminals; you do not order one per terminal.
A list of related PECs, Apparatus, and Comcodes is provided in Section 7. Be sure to check
the Sales Manual and/or DOSS before ordering since this information changes frequently.
Symbols Used in Figures: Modular jacks are shown by the triangle symbol. The 25-pair
connectors are indicated by shaded blocks. Generally, only one leg of an octopus cable is
shown. Unterminated wiring requiring cut down or other termination do not have symbol
designations.The 103A Connecting Block is a typical modular wall jack that provides cut-
down connections for building (station) wiring.
Voice Terminal and Adjunct Connections
Figures 4-27 through Figure 4-33 provide connection information for single-line and multiline
voice terminals. The single-line terminals can be located on-premises, off-premises, or out-
of-building. The MERLIN System multiline voice terminals can be used for out-of-building
service but must be within 2000 feet of the system cabinets (local power is required beyond
1000 feet for in-building sets and for all out-of-building sets). Off-premises service is not
available.
Diagrams for voice terminal adjunct connections are included with the specific feature
descriptions in Section 2.
Attendant Console Connections
Diagrams for attendant console connections are included in the “Attendant Console”
descriptions in Section 2.
Peripheral Equipment Connections
Diagrams for peripheral equipment connections are included with the specific feature
descriptions in Section 2.
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							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 auxiliary equipment connections are included with the specific feature
descriptions in Section 2.
SYSTEM 25
CABINET
PART OF
OCTOPUS
PART OF
CABLE
SIPZTN78SINGLE-LINEC2SIPW1B1C5
ORVOICEADAPT.TERMINAL
TN742(NOTE)
LEGEND:
ZTN78 - TIP RING CP
TN742 -ANALOG LINE CPB1 -TYPICAL-103A CONNECTING BLOCK*
C2 - OCTOPUS CABLE (WP90780) - PEC 2720-05P
C5 - MODULAR CORD (D4BU-87) FURNISHED WITH SET
W1- 4-PAIR INSIDE WIRING CABLE*
NOTE: RANGE LESS THAN 2000 FEET FROM SYSTEM CABINET, USE ZTN-78 CP.
RANGE MORE THAN 2000 FEET BUT LESS THAN 1300 OHMS† (LOOP RESISTANCE)
FROM SYSTEM CABINET, USE TN742 CP. FIVE SINGLE-LINE VOICE
TERMINALS CAN BE BRIDGED WHEN USING A TN742 CP; HOWEVER, ONLY TWO
MAY BE OFF-HOOK AT ONE TIME.
* FURNISHED BY INSTALLER
† - INCLUDES TELEPHONE/TERMINAL
Figure 4-27.On-PremisesSingle-Line Voice Terminal Connections
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							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
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