Control Unit; Modules - AT&T MERLIN LEGEND Key System Planning

Control Unit

Modules

Planning the control unit consists of deciding how to place the modules, setting
the system operating conditions, and numbering the system.
Certain modules are required for every system:
Processor module contains the memory that controls the system software
and features. It also contains the software and firmware that support built-in
system diagnostics and the built-in data modem used for remote
maintenance and system programming. The processor module is offered in
two sizes:
The small processor module supports a maximum of 24 lines and/or 56
stations.
The large processor module supports a maximum of 80 lines and/or 144
stations.
Power supply module provides power to the processor module and line and
station modules, and to each telephone and adjunct. Each carrier in the
control unit has one power supply module.
Line and station modules contain the jacks for connecting stations and
outside lines to the control unit. The type of jack on a module determines the
type of line or station that can be connected to it.
The line and station modules and the type(s) of jacks on each are shown in
Figure 2-1.
2-1
Modules