Modes Of Operation - AT&T MERLIN LEGEND System Reference Manual

Functional Description

Modes of Operation

Key Mode
The system can be programmed to operate in any one of three modes:
Key
Hybrid/PBX
Behind Switch
The mode of operation determines
the types of outside lines/trunks that can be connected to the system
how outside line/trunks are provided to users
the types of system operator consoles allowed
the features available and how they work
Table 4-2 at the end of this section summarizes the system's modes of
operation.
A Key system is the simplest way to provide users with more than one line from
a single telephone. Older Key systems have telephones that look like single-line
telephones except for a row of buttons, illuminated by incandescent lights when
active, across the bottom. The leftmost button is labeled "Hold," and the other
buttons are labeled with telephone numbers.
When the system operates in the Key mode, specific telephone company lines
are associated with specific line buttons (or keys) on each telephone. The line
buttons allow users to see activity on other telephones, join conversations, make
calls, or receive calls. Separate Intercom buttons are used to make and receive
internal calls.
The Key mode accommodates any one, or a combination, of the following kinds
of lines and facilities (DID trunks cannot be used on Key systems):
loop/start including basic lines, WATS, and FX
t i e t r u n k s
DS1 facility
Emulated ground-start lines
A standard Key system's lines are all loop-start. Loop-start connections
introduce a slight delay from the time the telephone company's central office
recognizes a call attempt and the time the call is processed. This delay is
minimal and virtually unnoticeable. Most residence and small business
telephones have loop-start lines.
Models of Operation 4-7