User Manual

Table Of Contents
Global objects and functions
Time synchronization
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Add and delete devices
For life check and replication the primary server has a list [BckUpSrv] of all known devices of a site. The
primary server automatically adds newly commissioned devices on the site to this list. Devices which are
removed from the site must be deleted manually in Xworks Plus (XWP) from the list in the primary server.
Check if all devices are online
The primary server performs a life check at regular intervals, to check that all devices of its site are online.
The interval between life checks is defined by the synchronization request period [SynReqp]. During this
period, the backup servers are checked one after the other in a cyclical process. The interval between two
life checks can be calculated as follows:
t SynReqp / Number of backup servers
.
A short synchronization request period and a large number of backup servers may involve a substantial
communications load. Take this into account when setting the synchronization request period in Xworks
Plus (XWP).
If one or more devices are not online, the primary server generates an alarm signal. The alarm is reset as
soon as all devices are online again and have been detected by the primary server. This ensures that
problems, such as the failure of a device, the termination of the HVAC-application processing of a device,
or faulty configuration (e.g., two primary servers in one site) are detected.
Monitor if the life check checks the backup server
Each backup server monitors its own periodic life check by the primary server. If a life check fails, or if no
primary server has ever carried out any life checks on this backup server, the backup server generates an
alarm. The backup server resets the alarm as soon as the primary server carries out a life check.
7.4 Time synchronization
Each automation station is assigned to a site.
The primary server is the time master. 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.
Desigo PX
Desigo PX
Desigo PX
PXM30/40/50
Desigo CC
10664Z19en_07
Primary Server Backup Server Backup Server