Panasonic KX-TD500 Features Manual page 385

Routing Procedure 3: Routing Flow Chart (2)
Is there your PBX's extension
number in the received digits?
Yes
Does that extension actually
exist?
Yes
No
Is it idle?
Yes
Calling to the specified
extension.
Features Guide
Analyzing digits sent from the
other PBX.
Does the leading 3 digits of
No
the received digits match your
PBX Code?
Is your PBX's CO access code
or extension number included
in the received digits?
Is there a CO access code of
No
your PBX in the received dig-
its?
Is "Trunk to Trunk
Restriction" of the selected
Trunk Group set to "Yes"?
Sends reorder tone.
No
Is it an extension number of
other PBX's?
No Trunk Group for making an
outgoing TIE call is decided
by a Routing Table.
Sends busy
tone.
Is "Trunk to Trunk
Restriction" of the selected
Trunk Group set to "Yes"?
Sends reorder tone.
Yes
No
Yes
Yes
No
Calling to CO.
Yes
No
Sends reorder tone.
Yes
No
Sends digits
received from one
PBX to another.
Yes
TIE Line Features
385