ATT System 25 Reference Manual

							External Alerts
External Alerts
Description
External Alerts provide standard station ringing at locations away from the called stations.
This feature can be used to activate an external alerting device such as a bell.
External Alerts supports the Trunk-Answer-from-Any-Station (TAAS) form of Night Service.
The feature can be used in conjunction with voice terminals located in noisy environments
and large areas such as warehouses, etc.The alerting device is activated whenever the
associated station is alerted.
A Supplemental Alert Adapter installed on a hybrid station allows the terminal user to
transfer incoming ringing to an alerting device located in some remote area. When the user
goes to the area, the alerting device rings for incoming calls to the user’s normal station.
Considerations
External Alerting enhances user ability to recognize incoming calls. Noisy environments, large
areas, and outside locations are candidates for external alerting devices.
Interactions
The following features interact with External Alerts.
Manual Signaling: Manual Signaling will not activate an external alerting device.
Night Service:When the system is in Trunk-Answer-from-Any-Station (TAAS) Night Service
mode, an incoming attendant-seeking call will activate the Night Service alerting device.
Power Failure Transfer: When the system
alerting devices are disabled.
Administration Requirements
Special Feature Port:
l An external alert operating as the
assignment on a ZTN78 Tip Ringis in the power failure transfer mode, the external
endpoint device on a station line requires a port
Line or TN742 Analog Line CP. (Specify special
feature port type = 253.) An external alerting device controlled from a Supplemental
Alert Adapter operates on the same line as the associated terminal and requires no
additional port assignment.
l Specify the PDC of the associated station (or 0 if alert is used with TAAS Night
Service).
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Hardware Requirements
Order line-activated alerting devices (e.g., bells) as required.
An alerting device operating on a line separate from a terminal requires a port interface on a
ZTN78 or TN742. Refer to Figure 2-26 for connection information.
Order the Supplemental Alert Adapter (PEC 2301-SAA) for controlling a remote alerting
device. A Supplemental Alert Adapter is installed in the line between the port CP and the
user’s MERLIN System terminal. The line requires a ZTN79 ATL Line CP. Figure 2-27
contains connection details.
Descriptions of the SIP (Station Interconnect Panel), TAE (Trunk Access Equipment), and
associated cables and adapters are provided under the heading “Connectivity” in Section 4.
SYSTEM 25
CABINET
PART OF
OCTOPUS
PART OF
CABLE
SIP
TN742
C2SIPW1
C5ORALERTINGB1
ZTN78ADAPT.DEVICE R1
LEGEND:
TN742 -
ZTN78 -
B1 -
C2 -
C5 -
R1 -
W1 -
*-
ANALOG LINE CPTIP RING CPTYPICAL-103A CONNECTING BLOCK*
OCTOPUS CABLE (WP90780) - PEC 2720-05P
MODULAR CORD (D4BU-87)
E1CM-50 RINGER OR EQUIVALENT PEC-31O19
4-PAIR INSIDE WIRING CABLE*
FURNISHED BY INSTALLER
Figure 2-26.External Alert Connections
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							External Alerts
SYSTEM 25PART OF
CABINETOCTOPUS
CABLEPART OF
SIP
ZTN79
C2SIPW1C1
B1 ADAPT.T1LINE CP
S1C8ALERTER C.U. V.T.
ALERTA1
LEGEND :
A1 -
B1 -
C1 -
C2 -
C8 -
S1 -
T1 -W1 -
*-
SUPPLEMENTAL ALERT ADAPTER - PEC 2301-SAA
TYPICAL -103A CONNECTING BLOCK*
MODULAR CORD (D8W-87)
OCTOPUS CABLE (WP90780)
MODULAR CORD (D4BU-87)
EXTERNAL ALERT
HYBRID TYPE TERMINAL
4-PAIR INSIDE WIRING CABLE*
FURNISHED BY INSTALLER
Figure 2-27.Supplemental Alert Adapter Connections
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							FEATURES AND SERVICES
Following
Description
This feature allows users who
at other inside voice terminals.are away from their own voice terminals to receive their calls
Following is functionally equivalent to internal Forwarding.
In order to have their calls follow them, users sign in their PDCs at the terminals where they
will be located temporarily. A call coming into the“home” terminal is redirected to the
terminal where the PDC is signed in (the “away” terminal). Signing in a PDC at a terminal
automatically signs the PDC out at any other terminal. PDCs always have an associated
home terminal. If a PDC is not signed in anywhere, calls to the PDC will ring at the home
terminal.
Signing in a FPDC automatically signs the FPDC out at any other voice terminal. However,
signing out a FPDC does not sign in the FPDC at another terminal. Calls to FPDCs not
signed in at any terminal may be directed to the attendant (administrable and strongly
recommended).
To sign in a PDC, the user goes off-hook at the away terminal, enters “ V V ” and then the
home PDC twice. The PDC sign-out procedure is similar; after going off-hook and receiving
dial tone, the user enters “ V V ”followed by the home PDC and then by a “0.” A “ V V 0 ”
entered at a voice terminal will sign out all PDCs and FPDCs signed in at that voice terminal,
except for the PDC normally assigned to it.Confirmation Tone is returned to a user who
correctly completes one of these procedures.
The call types or features listed below are voice terminal oriented (associated with stations
rather than PDCs) and do not follow a user who signs in at another terminal.
l
l
l
l
l
l
l
l
l
l
lAutomatic Intercom Calls
Callback calls when a queued-for facility becomes available
Calls ringing on Bridged Access (BA) buttons
Coverage calls
Directed Night Service calls
DGC Group Calls
Manual Signaling
Message Waiting indications
Outward/Toll Restriction
Personal Line Calls
Returning calls
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							Following
Calls Placed to A PDC:
Calls to a PDC that is not signed in at an“away” terminal are directed to the home terminal
and receive that terminal’s normal hunting or coverage treatment.
If a PDC is signed in at an away terminal, calls placed to the PDC fall into one of the
following categories:
l The general case—
calls placed from terminals other than the away terminal
l A special case—call placed from the away terminal.
(1) The General Case: The call will first be directed to the away voice terminal. Ringing will
occur at the away terminal if it is an on-hook single-line voice terminal or if it is a multiline
voice terminal with an idle System Access button.
A call unanswered at the away terminal will be directed back to the home terminal unless one
of the following busy conditions exists at the home terminal: (1) it is a multiline terminal with
all System Access buttons busy and with no idle coverage receiver or (2) it is a single-line
voice terminal that is off-hook, has no idle coverage receiver, and has no idle hunt-to station.
While either of these busy conditions exists at the home terminal, the call will not return to
the home terminal. Instead, it will continue to ring at the away terminal until answered or
timed out.
If either of the above two busy conditions ends at the home terminal while the call is waiting
at the away terminal, the call will be directed back to the home terminal. If the call is sent
back to the home terminal, it can be answered or it can receive the terminal’s hunting or
coverage treatment.The coverage treatment given to calls that are returning from an away
terminal differs in two respects from the treatment provided to calls initially directed to the
home terminal.First, the home terminal and its coverage station receive ringing
simultaneously, rather than having the coverage ringing delayed. Second, coverage terminals
will ring for calls returning to the home stations even if the coverage ring options of the home
terminal are “no ring.”Both of these coverage modifications expedite the answering of calls
that are returning to the home station from an away station.
Once the call is directed back to the home terminal, it is removed from the away terminal.
This is true even if the away terminal was busy but subsequently became idle after the call
was sent back to the home terminal.
(2) A Special Case: A call to a PDC placed from the same station where it is signed in will be
directed to the PDC’s home terminal.
Calls Placed to a FPDC:
When a valid FPDC is dialed, the call will be directed to the terminal where the FPDC is
signed in and will be provided the coverage treatment administered for that terminal. If the
FPDC is not signed in anywhere and if the attendant position is administered to handle these
calls, then the call will be directed to the attendant position. However, if the FPDC call was
placed from the attendant position, then it will not be redirected to the attendant but will
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							FEATURES AND SERVICES
instead be provided Reorder Tone.Finally, if the FPDC is not signed in, and if the attendant
position is not administered to handle these calls, then the calling party will receive Reorder
Tone.
For non-DID calls if an invalid FPDC is dialed, then the calling party will receive Reorder
Tone. If a DID call does not match any assigned number in the dialing plan, it will be
directed to the attendant or to Reorder Tone, as administered.
Considerations
Following provides maximum flexibility to system users who are away from their voice
terminals. In addition, visitors can receive calls by signing in an assigned FPDC.
For more information, see the “Personal Dial Code (PDC)” feature description.
Interactions
The following features interact with Following.
Bridging of System Access Buttons:Sign-in and sign-out procedures can be performed at
the destination station on either a System Access (SA) button or a Bridged Access (BA)
button. However, since Following calls always arrive on SA buttons, the destination station
must have at least one SA button.
Following calls arriving at a principal SA button are accessible at BA buttons on the bridging
station.
Callback Queuing: Calls that follow are queued on the busy “away” station, not the “home”
station.
Callback attempts to the originator do not follow.
Coverage: Calls to a signed-in FPDC receive the coverage of that terminal. Unanswered
calls to a PDC at an away terminal return to the home terminal and receive the home
terminal’s coverage treatment; they do not receive the away terminal’s coverage.
Forwarding: Either Following or Forwarding, but not both, can be active at a given time for a
particular PDC. Activation of one feature while the other is in effect overrides the other
feature.
Remote Access: Remote Access callers cannot use Following. However, Remote Access
callers can activate Forwarding; see the“Forwarding” feature description for information on
this capability.
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							Forwarding
Forwarding
Description
This feature allows users to direct their incoming calls to another (forwarded-to) voice
terminal where they will be located temporarily. Calls can be forwarded to inside stations or
to locations outside System 25. Figure 2-28 is a simplified block diagram of this feature.
CALLINGFORWARDINGFORWARDED-TO
STATIONSTATIONSTATION
Figure 2-28.Stages of Call Forwarding
Forwarding is similar to the Following feature.Both features enable users to answer their
calls at another terminal. The basic differences between these features are as follows:
l Users activate Forwarding at their own stations; the forwarded-to station can be
inside or outside System 25.
l Users activate Following at the “away” station, which must be inside System 25.
The procedures for activating the two features are different also. Refer to the “Following”
description for complete coverage of that feature.
Forwarding Calls to Stations Inside System 25
The user activates Forwarding to an inside station by dialing feature access code #70 and
then the forwarded-to extension number. If the activation is successful, the user receives
confirmation tone; if the attempt fails, the user hears reorder tone.
The user who forwarded calls to an inside station can deactivate Forwarding in either of
these ways:
l By signing in at the user’s own (the forwarding) station after returning there; this
procedure consists of dialing “ V V ” and then the user’s PDC twice.
l By signing out at the forwarded-to station before returning to the forwarding station;
this procedure consists of dialing “ V V ”followed by the user’s own PDC and then
“0”.
Calls forwarded to an inside station cannot forward again from the forwarded-to station.
A call unanswered at a forwarded-to inside station returns to the forwarding station after the
administered number of rings; if the forwarding station has Coverage, the call redirects. A
call forwarded to a busy inside station rings the forwarding station immediately; the call
returns ringback to the caller unless the caller has automatic Callback Queuing or Call
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							FEATURES AND SERVICES
Waiting is administered at the forwarded-to station.
Forwarding Calls to Locations Outside System 25
The user activates Forwarding to an outside station in one of the following ways:
l By dialing feature access code #70, the single-digit ARS access code, and the
forward-to number, then hanging up after hearing confirmation tone.
l By dialing feature access code #70, a pooled facility (trunk) access code, and the
forward-to number, then hanging up after hearing confirmation tone.
The forward-to numbers for outside calls must be dialed in one of the following ways:
l 7 digits,“1” plus 7 digits, 10 digits, or “1” plus 10 digits.
l A Speed Dialing code, such as #20.
l By adding # at the end of a code of more than 4 digits and less than 10 digits.
l By letting the system time-out after entering a code of more than 4 digits and less
than 10 digits.
If the forwarding activation attempt is unsuccessful, the user hears reorder tone.
Forwarding to an outside station is deactivated by signing in at the user’s own (the
forwarding) station inside System 25. The procedure consists of dialing “ V V ” and then the
user’s PDC twice. No procedure exists for signing out at an outside forwarded-to station.
No matter which ring option (“no ring,” “immediate ring,”or “delayed ring”) is administered
for the forwarding station’s SA buttons, the station will receive an abbreviated alert (single-
ring reminder) when a call is forwarded outside.
Forwarding to an outside location is enabled or disabled on a per-station basis through
system administration.In addition, forwarding calls to outside stations is limited by any
calling restrictions administered for the forwarding station.An outward-restricted station, for
example, cannot forward calls out of the system.Toll and facility access restrictions can
also prevent call forwarding.
A call forwarded to an outside station that is busy or does not answer is treated like any
network call; the caller receives busy tone or ringback. The call will not return to the
forwarding station.In certain circumstances, incoming outside calls that are forwarded to
outside locations may encounter an unusual sequence of tones. For example, the caller may
hear ringing, a pause, then busy tone.
Remote Access Forwarding
Forwarding to an outside number from a System 25 station can be activated by a Remote
Access user calling into the system on a dedicated Remote Access trunk or on a shared
trunk while Night Service is in effect; the caller must use a barrier code. Remote Access
Forwarding to other inside stations is not allowed.
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							Forwarding
After dialing the Remote Access trunk and the barrier code, the caller receives second dial
tone. The caller then enters access code #70 and the PDC of the forwarding station;
confirmation tone followed by silence is returned if a valid PDC was dialed. Finally, the
remote caller dials the outside forward-to number and hears confirmation tone.
To cancel Remote Access Forwarding, the remote caller repeats the activation procedure but
substitutes “0” for the outside forward-to number.
Considerations
Forwarding helps System 25 users avoid missing important calls while they are absent from
their “home” terminals. It complements coverage features by allowing users to answer their
own calls remotely rather than have other users take their messages. Calls can be
forwarded from all types of voice terminals except rotary-dial sets.
A forwarded-to multiline voice terminal must have at least one System Access (SA) button, If
a user attempts to forward calls to a station without a SA button, reorder tone is returned,
and the attempt is blocked.
In general, the only calls that forward from a terminal are internal calls, transferred or
attendant-extended outside calls, Remote Access trunk calls, and DID calls. At multiline
terminals, such calls ring at SA buttons.
The following call types or features are station-oriented (rather than PDC-oriented) and do
not forward:
l Automatic Intercom calls
l Callback calls when a queued-for facility becomes available
l Calls ringing on Bridged Access (BA) buttons
l Coverage calls
l Directed Night Service calls
l DGC Group calls
l Manual Signaling
l Message Waiting indications
l Outward/Toll Restriction
l Personal Line calls
l Returning calls.
An attendant’s PDC can serve as a forward-to point for other stations. Calls placed to the
attendant’s PDC can be forwarded by the attendant.
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							FEATURES AND SERVICES
A given station can receive forwarded calls from any number of other stations.
Note:When incoming trunk calls are forwarded to outside locations, severe
attenuation of the voice signal may occur.
Interactions
The following features interact with Forwarding.
Account Code Entry, Forced: Stations with this feature administered for all calls cannot
forward calls to any outside numbers.
Stations with this feature administered for “dial 0 or
1” calls can forward calls to any outside number except for “dial 0 or 1” numbers.
Attendant Call Extending: Calls extended by an attendant to a forwarding station will be
given normal Forwarding treatment.
Bridging of System Access Buttons:Since forwarding is a station-oriented feature, it can be
activated and deactivated for a forwarding principal station only at a System Access button
on that station. If forwarding is activated at a Bridged Access button on a bridging station, it
affects calls to that station only.
Callback Queuing: Calls that forward are queued for the busy “away” station, not the
“home” station.
Callback attempts to the originator do not forward.
Conference: If one of the called parties for a conference is a forwarding station, its
forwarded-to station will be the conference facility.
If a conference call is transferred to a forwarding station, it will be given normal Forwarding
treatment.
Coverage: When a station has both Coverage and Forwarding in effect, calls are routed first
to the forwarded-to station.If not answered there within an administered number of rings,
calls ring at the forwarding and coverage stations and stop ringing at the forwarded-to
station.
When forwarding to an outside number, coverage may only occur in one case: the forwarding
had been activated using a trunk group’s facility access code (not ARS), the forwarding
cannot be completed because the trunk group is busy, and the forwarding station is not
busy. In this case, the call will ring at the forwarding station and its coverage stations.
Direct Station Selection (DSS): DSS or FLEX DSS cannot be used when forwarding calls
(that is, dialing #70 and pressing a DSS or FLEX DSS button for the forwarded-to station is
not a valid procedure).
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