BT 2+8, Installation And Maintenance Manual

Page: 8 / 40

Introduction
1-4
1.1.4.4
Warn tone
Warn tone is provided to indicate an incoming call to the system where
an extension user who would normally be in a position to take the call
cannot because that extension may be:
- programming
- being rung
- setting up an outgoing call.
Note The CCU regards an outgoing call as being in progress during:
MF signalling - the first 20 seconds following exchange line seizure.
Pulse signalling - the first eight seconds from
t}l
e end of each break
pulse.
The warn tone lasts for one second and is not repeated. The external
party is disconnected from the system during the warn tone in order for
the
CCU
to apply it.
1.1.5
Ringing defaults
Table 1.1
At switch-on, when in Keysystem Mode, the
CCU
sets all extensions to
ring if an incoming call arrives. Individual extensions can be prevented
from ringing by programming them off. The ringer default on is a
mandatory requirement to ensure that incoming calls are indicated when
power is restored after a power failure.
Some ringers can be programmed off for each line and some cannot.
Refer to the following table.
Incoming ring defaults
PBX mode
Keysystem
EXCL line mode
Line 1
Line2 Line 1 Line2 Line 1 Line2
Ext.
20
No
No No Yes No NIA
Ext.
21
NIA NIA Yes No NIA No
Ext. 22 NIA NIA Yes Yes Yes NIA
Ext.
23 NIA NIA Yes Yes Yes NIA
Ext.
24
NIA NIA Yes Yes Yes
NIA
Ext.
25
NIA NIA Yes Yes Yes
NIA
Ext. 26 NIA NIA Yes Yes Yes NIA
Ext.
27 NIA NIA
Yes
Yes Yes NIA
No = Ringer cannot be programmed off for that line
Yes = Ringer can be programmed off for that line
NI A= Not applicable
TPU
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