Direct Inward Dial Operation; Two-Way, Loop Dial Repeating, Tie Trunk Operation - Nortel Enterprise 1000 Reference Manual

Analog Trunk Cards - NT8D14 Universal Trunk Card

Direct inward dial operation

Incoming calls
An incoming call from the CO places a low-resistance loop across the tip and
ring leads. See Figure 19 on page 65 and Figure 20 on page 66. Dial pulses or
DTMF tones are then presented from the CO. When the called party answers,
the universal trunk card reverses battery and ground on the tip and ring leads
to the CO. The trunk is arranged for first party release. The CO releases the
trunk by removing the low-resistance loop, at which time normal battery and
ground are restored at the near-end. This also applies to incoming tie trunk
calls from a far-end PBX.
Note: The near-end may be configured for immediate start, delay dial,
or wink start.

Two-way, loop dial repeating, tie trunk operation

Incoming calls
In an incoming call configuration, the far-end initiates a call by placing a low-
resistance loop across the tip and ring leads. See Figure 21 on page 67 and
Figure 22 on page 68. This causes a current to flow through the battery feed
resistors in the trunk circuit. Address signaling is then applied by the far-end
in the form of DTMF tones or dial pulses. When the called party answers, an
answer supervision signal is sent by the software, causing the Succession
CSE 1000 to reverse battery and ground on the tip and ringleads to the far-
end. Far-end disconnect is initiated by opening the loop while the near-end
disconnect is initiated by restoring normal battery and ground. The operation
represented in Figure 21 and Figure 22 also applies to incoming DID trunk
calls from a CO.
Note: Where no near-end answer supervision is provided, the party at
the far-end hangs up after recognizing near-end call termination.
Outgoing calls
In an outgoing call configuration, the universal trunk card is connected to an
existing PBX by a tie trunk. See Figure 23 on page 69. An outgoing call from
the near-end seizes the trunk facility by placing a low-resistance loop across
the tip and ring leads. Outward addressing is then applied from the Succession
CSE 1000 in the form of DTMF tones or dial pulses. If answer supervision is
provided by the far-end, reverse battery and ground on the tip and ring leads
Succession Communication Server for Enterprise 1000 Circuit Card Reference Guide
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