Defining The Line Boards - Comdial DXP Plus Manual

DXP Plus General Description

3.2 Defining The Line Boards

The DXP Plus accepts several different types of lines. In order to use these various lines, you must
install the correct line board. The following list details all of the current DXP Plus line boards.
Direct Inward Dialing Line Board:
Direct Inward Lines (DID) are incoming only and are employed to reduce the number of channels
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between the DXP Plus and the Central Office (CO). DID lines allow incoming CO calls to reach
internal intercom extensions without going through the attendant station. DID operation requires
a group of published directory numbers provided by the CO. The number of DID lines is limited
only by the number of installed DID boards. The DID translation tables have limits that may
affect DID capacities. The system supports a maximum of 400 DID lines.
Loop-Start Line Board:
The loop-start line board provides system interface for loop start lines. Loop start lines are the
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most common CO line type (loop-start lines do not usually offer disconnect supervision)
Multi–Purpose Line Board:
The multipurpose line board provides system interface for ground start lines, loop start lines, and
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E & M Tie lines; these are typically the three line types that the central office (CO) makes
available for connection. The multipurpose line board is programmable for each line type. You
can have a maximum of two Tie lines on each multipurpose line board.
E1 Line Board (available for international applications):
The E1 board provides 30 channels of voice transmissions over a single, four-wire, 120 ohm
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cable or over two 75 ohm coaxial cables using multiplexing techniques. The system accepts a
maximum of eight E1 boards.
T1 Line Board (available for domestic U.S.A. applications)
The T1 board provides eight, 16, or 24 channels of voice transmissions over a single, four-wire,
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cable using multiplexing techniques. The system accepts a maximum of ten E1 boards.
GCA40–130
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