If you have any bridged appearance and or call coverage buttons, you can set the type of ringing (coverage ring) that should be used when a call alerts on any of those buttons. The options are to use normal ringing, a single non-repeated ring (abbreviated ring) or no ring. The coverage ring setting is only used if you do not already have a connected call. If you already have a connected call in progress, the shorter of the coverage ring and attention ring settings is used.
This is a user setting which moves with you if you hot desk another phone.
To do this during a call, press the PHONE key and then press Features.
Ring - Use normal ringing.
Abbreviated - Use a single non-repeated ring (abbreviated ring).
Off - No ring.