Iwatsu ICON Series IX-5910 Owner's Manual page 294

Press Exit to return to the main display. The new ringing mode
selection will appear on the display
Menu Operations in System Ringing Mode (Forced Night)
When a system is in System Ringing Mode, pressing existing Group Night
Mode key from an Iwatsu ICON Series (IX-5810, IX-5910, and IX-5930)
attendant position will take you to the Select Ringing Mode screen with
limited selections. The menu will prompt the attendant to select either In
Forced Night (Group Night) or In System Mode.
This operation has a Group Night override for system ringing. Incoming
calls through a specified trunk group will generate ringing based on the
Night ringing table
Key Lamp Indication for Day-1, Day-2, Day-3, and Night Mode
The System Night Mode key will change the LED lamp status based on the
System Ringing mode. The LED lamp indication is reflected for the ringing
mode on all Iwatsu telephones (legacy and ICON Series) with a Night Mode
key.
Day-1 Ringing Mode = No lamp indication.
Day-2 Ringing Mode = Slow red flash.
Day-3 Ringing Mode = Fast red flash.
Night Ringing Mode = Solid red flash.
Note: Iwatsu ICON Series Self-Labeling Key name change is not supported
with the Multiple Ringing Mode.
ATTENDANT POSITION USER GUIDE - 274