MERLIN LEGEND Communications System Release 5.0
Feature Reference
555-650-110
Issue 1
June 1997
Features
Page 128
Centrex Operation
Single-Line Telephones
3
When single-line telephones are used in Behind Switch mode, a prime line is
assigned automatically to the extension.
Centrex service supports only touch-tone telephones.
When single-line telephones are connected directly to a prime line, they have
limited functionality because they cannot access communications system features
or make intercom calls. They can, however, use all the Centrex features by dialing
the proper access codes.
If a single-line telephone has the Idle Line Preference programmed for an ICOM
Ring button, the user has complete use of all communications system features.
Access to Centrex lines and features is gained by dialing the Centrex access
code. However, a single-line telephone cannot use the communications system’s
Conference, Transfer, or Drop because the switchhook flash goes directly to the
Centrex line and is not intercepted or interpreted by the communications system.
Single-line telephones should be connected using a 012, 016, or OPT module. If a
single-line telephone is connected to an MFM, it cannot send a switchhook flash.
In Hybrid/PBX mode, special ringing patterns are used on single-line telephones
to differentiate various call types (personalized ringing is not available):
■
Centrex intercom calls are indicated by 2-burst ringing.
■
Centrex special or priority calls are indicated by 3-burst ringing.
■
Outside calls are indicated by 3-burst ringing.
■
Centrex special signaling is not indicated.
Feature Interactions
3
Caller ID
In Release 3.0 and later systems, companies may use the 800 GS/LS-ID
module to capture calling number identification information (subscribed to
from the central office on loop-start lines only, if available). MLX display
telephones in these systems show the number of an outside call received
on a line connected to the module. However, if the customer also
subscribes to call waiting through Centrex, the number of the waiting call
is not shown on the MLX display.
Calling Restrictions
Centrex users should not be assigned calling restrictions because the
calling restrictions should be assigned through the CO.
Conference
In Behind Switch mode, the fixed-function Conf button applies to Centrex
operation and is not recognized by the communications system. A button
can be programmed for communications system Conference.
Drop
In Behind Switch mode, the fixed-function Drop button applies to Centrex
operation and is not recognized by the communications system. A button
can be programmed for communications system Drop.