Nortel Networks 1000 User Manual

Page 520

520

NT8D14 Universal Trunk card

interval between ringing signals exceeds the switchhook flash time of 512
milliseconds, software assumes far-end disconnect. This causes the call to
be presented to a console loop key and then immediately removed.

The reverse-wiring compensation feature operates as follows. If an
apparent disconnect takes place immediately after the first ringing signal,
the software time stamps the event and temporarily removes the call from
the console loop key.

If another such ringing/disconnect event occurs during the No Ringing
Detector (NRD) time, the trunk is considered "possibly reverse wired" and
a threshold counter is incremented. Calls on trunks identified as possibly
reverse wired is presented to the attendant during the initial ring, removed,
and then continuously presented after the second ring. If a call on a
possibly reverse-wired trunk is abandoned before the attendant answers, it
is disconnected after the NRD timer expires.

Figure 145
Ground start call states - incoming call from CO/FX/WATS

Nortel Communication Server 1000

Circuit Card Reference

NN43001-311

02.06

Standard

27 August 2008