Lucent Technologies MERLIN LEGEND Release 5.0 Feature Reference page 156

MERLIN LEGEND Communications System Release 5.0
Feature Reference 555-650-110
Features
Centrex Operation
A switchhook flash, feature access code, or Feature button-press is
interpreted as intended for the Centrex service.
In limited Centrex service:
The communications system operates in Key or Hybrid/PBX mode.
Intercom calls can be made between communications system extensions.
Calls to Centrex extensions require access to a prime line.
A switchhook flash, feature access code, or Feature button-press activates
the communications system feature, not the Centrex feature.
Outside calls using Centrex service are made through individual prime
lines or pooled prime lines.
Other types of lines (tie, DID, and T1) can also be used for outside calls
without using Centrex service.
Considerations and Constraints
To prevent user confusion, extension numbers in the communications system
should reflect the ending digits of the Centrex prime line number. For example, an
extension with a Centrex prime line number of 4322 should have an extension
number of 4322 in a 4-digit (Set Up Space) numbering plan, 322 in a 3-digit
numbering plan, or 22 in a 2-digit numbering plan.
page 583
Centrex service supports only touch-tone telephones.
With full Centrex, the Recall or Flash and fixed-function buttons (Conf, Transfer,
and Drop) control Centrex functions. Corresponding communications system
functions can be programmed on buttons if any are available (see
Flash'' on page 511
Flash and fixed-function buttons control communications system functions. In
either case, some Centrex functions can be programmed on the Directory and on
Auto Dial buttons, but not on other unused feature buttons.
Centrex service is supported only on loop-start lines. Some central offices offer
Centrex features on ground-start trunks; however, the MERLIN LEGEND
Communications System does not support Centrex features on ground-start
trunks or ISDN facilities. Centrex service on T1 trunks with loop-start emulation is
also not supported.
Full Centrex (Behind Switch mode) does not support data communications.
During high-traffic periods, the loop-start lines used by Centrex can cause glare
when multiple calls access the same line simultaneously. Loop-start lines also
have higher cable losses than ground-start lines/trunks and cannot guarantee
secure toll restriction.
provides information about numbering plans.
for additional information). With limited Centrex, the Recall or
3
''System Renumbering'' on
Issue 1
June 1997
Page 124
''Recall/Timed