Each automation station is assigned to a site.

The primary server is the time manager. It represents the system time within a given site. The primary server synchronizes the time in the other automation stations at regular intervals.

If the primary server receives a time synchronization request which triggers a time change, the primary server synchronizes the time in the other automation stations.

The primary server transmits the time in UTC format (Coordinated Universal Time) to the other automation stations (backup servers) and in UTC format or local time format to the third-party BACnet devices.

The backup server then triggers time synchronization of its recipients configured in Xworks Plus (Desigo room automation server, third-party server, third-party BACnet devices). This can be in either UTC or local time format.

Periodic synchronization

The time synchronization interval is defined in the property TimeSynchronizationInterval [TiSynIvl] (default value: 150 minutes). The property can be configured in Xworks Plus (XWP) and adapted to the specific situation via a switchable [AlgnIvl] offset [IvlOfs]. How these three properties function is defined in the BACnet standard and implemented accordingly.

Add and delete devices

For time synchronization, the primary server has a list [TiSynRcp] containing the recipients configured in Xworks Plus (XWP) and all known backup servers of its site.

The primary server automatically adds newly commissioned backup servers on the site to the list [TiSynRcp].

Backup servers which are removed from the site must be removed manually from the primary server list in Xworks Plus (XWP).

Link the system time of a site with operator units

The network-capable operator units do not belong to a site. The primary server does not update the time in the operator units. The client can read and update the time, if required.

Daylight saving time changeover

The daylight saving time changeover does NOT take place in the primary server. Each automation station makes this switch independently.

The date of the daylight saving changeover is set as a parameter in the primary server. The primary server replicates the date on the backup server. The official (Central European) changeover date is set as default.

The local time in an automation station is a calculated variable. The calculation is based on the internal time in UTC format, the property UTC offset [UtcOfs] and the date of the summer and winter time changeover.

See Desigo CC User Guide (A6V10415471).