Panasonic KX-TD500 System Reference Manual page 476

(Supplement 2)
The table below shows whether an extension which has DND assigned
rings or not and how its PDN indicator lights, when it receives a call.
Also shows whether the other extension which has the extension's SDN
assigned rings or not and how their SDN indicators light, when the
extension having DND receives a call.
Type of call arriving at
setting extension
Extension call
Attendant Console call
DIL (1:N) call to PDN
DIL (1:1) call to PDN
DID call
DISA call
DIL (1:N) call to Group
CO/Single CO
DIL (1:1) call to Single
CO
Other calls
1 DND tone is sent to the caller.
Other extension Extension which
which has SDN has DND assigned
assigned or not (PDN)
No Indicator off
No ring
Yes Green 240 wink
No ring
No Indicator off
No ring
Yes Green 240 wink
No ring
No
Green 240 wink
No ring
Yes
Green 240 wink
No
Ring
Green 240 wink
Yes
No ring
No
Indicator off
No ring
Yes
No
Indicator off
No ring
Yes
Red 240 wink
No ring
Green 240 wink
Ring
Indicator off
No ring
4-D-14
Extension which has
SDN assigned (SDN)
1
Red 240 wink
Ring
1
Red 240 wink
Ring
Lights on in red
No ring
Red 240 wink
Ring
Indicator off
No ring
Indicator off
No ring
1