AT&T MERLIN LEGEND Release 2.0 System Programming Manual page 116

Programming Procedures
Select System Numbering Plan
CAUTION:
To avoid possible loss of system programming information, renumber
the system before you program the rest of the options described in this
chapter.
Three system numbering plans are available. These should appear on System
Planning Form 2a. The three plans are as follows:
The 2-digit plan (for systems with fewer than 50 extensions and no plans
to exceed that number within two or three years): Each of the first 58
station jacks is assigned a 2-digit extension number, beginning with 10
and ending with 67. Any remaining extensions are assigned 4-digit
numbers, beginning with 6800 and ending with 6885.
The 3-digit plan (for systems with 50 or more extensions or plans to grow
to that number within the next year or so): All extensions are assigned a
3-digit number, beginning with 100 and ending with 243.
The Set Up Space plan (for systems with a need to customize their
extension numbers or use extension numbers of varying lengths — 1 to 4
digits): All extensions are assigned 4-digit numbers in the 7000 range.
Extension numbers 1000 through 6999 are also available for use when
you renumber.
In all three numbering plans, the system assigns 3-digit extension numbers to
pools (Hybrid/PBX only), calling groups, paging groups, remote access codes,
the Listed Directory Number, park codes, and Idle Line Access (Key and
Behind Switch modes). In addition, the system assigns 9 for Automatic Route
Selection (Hybrid/PBX only) and Idle Line Access (Key and Behind Switch only).
Zero (0) represents a special extension number — actually a fixed dial code — for
the primary operator or QCC queue. Any extension number except 0 can be
renumbered.
Extension numbers can be composed of any combination of digits; however, no
number can begin with 0 Trunk numbers (801 – 880) are not considered to be
extensions and cannot be renumbered.
The system does not provide a message to indicate a successful renumber
when either the 2-digit or 3-digit numbering plan is selected. For the set up
space numbering plan, the system provides a message indicating that all
extensions are in the 7000 range.
Select System Numbering Plan
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