Nortel Circuit Card Installation Manual page 651

Table 200
DX signaling – outgoing calls with originating party release on tandem connections
(Part 2 of 2)
Condition
Near end on hook first, network taken down
Far end on hook, trunk idled
Table 201
DX signaling – incoming calls with originating party release on tandem connections
(Part 1 of 2)
Condition
Idle
Seizure
(Can be arranged for IS, DD, or WS)
(near-end ready for digits)
Dial CO/FX/WATS and office DN
Stored digits outpulsed on CO/FX/WATS trunk
after ground detection if a ground start, but after 3
seconds if a loop start
If answer supervision: pseudo-answer supervision
is sent approximately 13 seconds after last dial
pulse received
NT8D15 E&M Trunk card
Current in
signaling lead
Current flow
No current flow
Current in
signaling lead
No current flow
Current flow
Current flow interrupted
for each pulse
No current flow
Circuit Card Description and Installation
Page 651 of 906
State of trunk
detector
Low
High
State of trunk
detector
High
Low
Low-high-low
for each pulse
Low