AT&T MERLIN LEGEND Release 3.1 System Planning Manual page 42

Planning Module Placement
One extension number is automatically assigned to each extension jack,
whether or not equipment is connected to it, except for the 008 MLX, 408
GS/LS-MLX, and 008 OPT modules:
008 MLX and 408 GS/LS-MLX Modules. Two extension numbers are
assigned to each physical jack: the first for an MLX telephone and the
second for any equipment connected to the telephone through an MFM,
ISDN terminal adapter (such as the ExpressRoute 1000 or 7500B data
module), or any 2B data desktop video endpoint.
NOTE:
When using the 008 MLX or 408 GS/LS-MLX module for data or video,
you must use Version 28 of the module.
008 OPT Module. The system recognizes this module as an 012 module.
Therefore, even though the OPT module has only 8 physical jacks, it uses
12 ports of capacity. An extension number is assigned to each of the 8
physical jacks.
This section contains instructions for calculating the system's extension
capacity according to the number of certain module types.
Planning Form Instructions
1. In the table under the Extension Capacity section of Form 1, fill in the
number of each type of extension module on the appropriate line of the
Number of Modules column.
2. Add the column and record the result at the bottom of the column
(System Totals line).
3. For each module, multiply the value in the Number of Modules column by
the value in the Physical Jacks per Module column and record the results
on the appropriate line in the Physical Jacks by Module Type column.
4. Add the column and record the results at the bottom of the column
(System Totals).
5. To determine the number of extensions assigned for each module type,
multiply the value in the Physical Jacks by Module Type column by the
value in the Extensions Assigned column and write the results in the
appropriate row in the Total Extensions Assigned column.
NOTE:
Since the system assigns an additional four extensions to each 008 OPT
module, you must first calculate the Extensions Assigned by multiplying
the number of 008 OPT modules (noted in the Number of Modules
column) by 4 and then add this subtotal to the number noted in the
Physical Jacks by Module Type column.
6. Add the column and record the result at the bottom of the column
(System Totals).
Control Unit Configuration
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