30 BERUZ - Times at which Class of Service Switchover is to occur

Stations (configured by AMO SCSU and AMO SBCSU) are allocated two classes of service COS1 and COS2) in their line tables. A class of service contains the authorizations of a station. An identifier (COS pointer) in the line tables indicates which COS is active, i.e. which of the station’s authorizations are currently activated; this is usually COS1.
AMO SCSU and AMO SBCSU subdivides stations into COS switchover groups. This is performed in order to group stations so that a certain COS can be switched active for all of them. The COSX groups are independant of other station groups formed by other features.
If no specific allocation has been made, a station belongs to COSX group 0. Stations with an active key switch (KEYSTN) are not switched over, but they are still assigned to a COSX group.

The classes of service can be switched over from a station, from an attendant console, y means of AMO BERUM, via data channel, and/or by means of a timed switchover.