AT&T MERLIN LEGEND Release 3.1 System Planning Manual page 44

Planning Module Placement
— Group all 800 DID, 100D, 800 NI-BRI, and 400EM modules
2. For each line/trunk and extension jack on each module, write the type of
jack (
keeping in mind the following:
Each 100D module is assigned 24 logical IDs, even though the
module has only 1 physical trunk jack.
Each 800 NI-BRI module is assigned 2 logical IDs per physical trunk
jack for a total of 16 logical IDs.
The 008 OPT module is assigned 12 logical IDs, even though the
module has only 8 physical extension jacks.
Power-failure transfer (PFT) jacks are not assigned logical IDs.
NOTES:
1. If the system will have 1 or more PFT telephones (maximum: 20),
2. You need a ground-start button on a PFT telephone connected to a
together according to type; this may save time in system
programming.
NOTE:
Due to limitations in the 391A, 391A1, and 391A2 power supplies,
the number of 800 NI-BRI modules plus 100D modules in a single
carrier cannot exceed three. If you have more than three modules,
you must install the additional modules in an expansion carrier.
This restriction does not apply to the 391A3 power supply.
X = extension; and L/T
indicate on the Control Unit Diagram the modules that will have PFT
telephones connected to their PFT jacks; write
A PFT telephone can be connected to a PFT jack on a 400, 400
GS/LS/TTR, 800, 800 GS/LS, 800 GS/LS-ID, 408, 408 GS/LS, or 408
GS/LS-MLX module. Touch-tone PFT telephones must be
connected to jacks with touch-tone lines/trunks.
ground-start trunk.
= line/trunk) and the associated logical ID,
Control Unit Configuration
PFT in the modules.
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