Section 700 - Operation
When a DN is assigned to an FF key on another telephone, it is considered a Non-Primary Directory
Number (NPDN). Up to three NPDN appearances of the same DN may be assigned to keys on a
telephone. This allows calls to the DN to appear on multiple telephones. The calls ring in on a
specified basis - immediate, delayed, or no-ring.
A telephone may only have one PDN (on up to three keys) but may have multiple NPDNs with up to
three appearances of any one NPDN.
Example Directory Number assignments for Extension 200
When a caller originates a call, the call appears on the first available PDN key. If all PDNs are
unavailable, the call will select the EXT LED.
When calls come in to a DN, the call appears on the first available DN key. If the call is to your PDN
and no PDN key is available, the call appears on the EXT LED.
Directory numbers may be assigned to FF keys 25-32. These are non-appearing keys.
Intercom voice calls only go to the PDN extension but light the corresponding NPDN keys red. A tone
call follows the appropriate ring status (immediate ring, delayed ring, etc.) for any extension.
To originate a call using a Primary Directory Number:
1. Lift the handset or press the ON/OFF key.
2. If dialing an outside call, dial the outside line group access
code (9, 81-84).
3. Dial the phone number or extension number.
DBS 576 (USA), issued January 1999
Chapter 5. Key Telephone Features
Intercom dial tone
The first available PDN key lights.
• Outside dial tone
• CO XXX displays (where XXX = line
Dialed number displays