AT&T MERLIN LEGEND Release 4.0 Feature Reference page 549

Feature Reference
NOTE:
Extensions 0 and 100 both refer to the same operator position in the 3-Digit
Numbering Plan.
Extensions default to 3-digit extension numbers beginning with 100 and ending
with 243.
The extension numbers shown for Multi-Function Modules (MFMs) (300-499) are
reserved for MLX extension jacks. These numbers are automatically assigned
by the system to adjuncts (such as a data terminal, answering machine, or fax
machine) connected to an MLX telephone using an MFM or terminal adapter.
The extension number assigned to the MFM adjunct is the extension number
assigned to the MLX telephone increased by 200. For example, if the extension
assigned for an MLX telephone is 125, the extension for the adjunct on that
telephone is 325. In this example, a call can be made to the telephone by
dialing
125
NOTES:
1. The extension numbers are reserved whether or not an MFM adjunct is
connected to an MLX telephone.
2. If you renumber the extension number of the telephone, the system
does not automatically change the extension number of the MFM.
Set Up Space Numbering Plan
The Set Up Space numbering plan is designed for businesses that want to
customize their system numbering plans and assign extension numbers that
vary in length (1 to 4 digits). Variable-length extension numbers may be more
meaningful for the business or more convenient for users; 1-, 2-, 3-, and 4-digit
numbers can be used in the same system. As an example, hotels and motels
may want to renumber extensions to match room numbers, and to renumber
extensions for services (such as Housekeeping or Room Service) to more
convenient 1-digit extension numbers.
Figure 43 shows the numbers automatically assigned by the system when you
renumber the system using the Set Up Space numbering plan. As shown in
Figure 43, the system reassigns extension numbers beginning with 7100 and
ending with 7299. This makes all numbers beginning with 1 through 6 available
for use in renumbering extension numbers. These new extensions can be from
one to four digits long.
or to the adjunct by dialing .
325
System Renumbering
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