Nortel ICS Install Manual page 466

466 / System prgrming
Tips -
programming change on a newly-installed Norstar system.
Each increase in length places the digit 2 in front of any
existing DN. For example, if DN 234 was increased to a
length of 4, the new DN would be 2234.
If the DN length is changed so that a conflict is created with
the Park prefix, external line access code, direct-dial digit, or
any line pool access code, the setting for the prefix or code is
changed to None, and the corresponding feature is disabled.
Modular ICS 7.1 Installer Guide
A DN length change, if required, should be the first
Do not change DN length immediately after a
system startup.
You must wait for at least two minutes after a
system startup before you change the DN length.
Data devices which use the B2 channel drop calls
when the DN length is changed. Digital phones
retain their calls because they only use the B1
channel.
The DN length change is completed within two
minutes, depending on the size of the installed
Norstar system. System response may briefly
slow down during this time. You cannot re-enter
programming during this time. If you enter the
programming access code, the message
In use: SYSTEM appears on the display.
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