Inter-Tel CS-5400 Manuale Utente

Single Line Endpoints

Page 107

Off premises extensions are remote single line DTMF endpoints connected to the Inter-Tel sys-
tem through telephone company OPX circuits (or customer-provided circuits). 

OPX phone users gain access to the features by hookflashing/recalling (pressing and releasing
the hookswitch quickly) and entering feature codes. 

Some telephone company OPX networks do not recognize certain single line phone ring
cadences used in the system. This incompatibility results in an inability to provide certain ring
signals to OPX phones. Because of this, the system is equipped with an endpoint option known
as Extended Ring Cadences, which allows the ring cadences be altered for individual single
line circuits.

Table 17 shows the different standard and extended ring cadences for the various types of sin-
gle line endpoints used on the Inter-Tel telephone system in the United States.

When a single line endpoint receives an incoming call, if the system has adequate Caller ID
resources, the single line endpoint displays the username and IC extension of the calling party.
This feature allows the single line endpoint to use the Caller ID information to perform certain
functions.

This feature is supported by single line endpoints, including endpoints and fax machines con-
nected to an IP SLA or SLA single line port. The single line endpoint connected to the single

Single line phone con-
nected to IP SLA, SLA, 
or T1 OPX

Standard IC Ring

A repeating 2-sec cadence that rings twice. 
Each ring lasts 200 ms and is separated 
from the next ring by 400 ms of silence. The 
remaining 1.2 sec is silent.

Extended IC Ring

A repeating 6-sec cadence that rings twice. 
Each ring lasts 800 ms and is separated 
from the next ring by 400 ms of silence. The 
remaining 4 sec are silent

Standard CO Ring

A repeating 6-sec cadence that rings once 
for 2 sec followed by 4 seconds of silence.

Extended CO Ring

Same as Standard CO Ring cadence.

Model 8560, Model 
8520, Professional, 
Executive, Standard 
and 
Associate MDPM

Standard IC Ring

This cadence has two 250 ms rings every 2 
sec.

Extended IC Ring

A repeating 3-sec cadence that rings once 
for 1 sec followed by 2 sec of silence.

Standard CO Ring

A repeating 6-sec cadence that rings once 
for 2 sec followed by 4 sec of silence.

Extended CO Ring

A repeating 6-sec cadence that rings once 
for 4 sec followed by 2 sec of silence.