Nortel Networks Circuit Card Manual De Usuario

 NTCK16 Generic Central Office Trunk cards

The Central Office initiates a call by applying ringing between the tip and ring 
wires. If the call is answered, the ringing detector on the trunk card is 
switched out and a low resistance dc loop is placed between the tip and ring 
leads.

On trunks configured for battery supervision, the battery detector records the 
polarity of the tip and ring wires and sends an answer acknowledge signal to 
software.

To initiate a call, the CS 1000S, CS 1000M, and Meridian 1 switches out the 
ringing detector and places a low resistance loop across the tip and ring leads. 
On trunks configured for battery supervision, the trunk card sends a seize 
acknowledge signal to software.

The system sends digits in the form of Dual Tone Multifrequency (DTMF) 
tones or pulse digits. When the far-end answers, the Central Office reverses 
polarity. If the trunk is configured for battery supervision, it sends a polarity 
reversal message to software.

There are two ways the Central Office can disconnect the call:

•

by applying busy tone toward the CS 1000S, CS 1000M, and Meridian 1. 
If the trunk card is configured to detect busy tone, it will send a 
disconnect message to software.

•

by reversing battery. If the trunk card is configured to detect battery 
reversal, it will send a disconnect message to software. When the unit on 
the trunk card has been idled, the trunk card sends a release confirm 
message to software.

The CS 1000S, CS 1000M, and Meridian 1 disconnects the call by removing 
the loop between the tip and ring leads and replacing the ringing detector. 
Trunks configured for battery supervision send a release confirm message to 
software.