Siemens SIMATIC S7-400 Operating Instructions Manual page 77

If there is power down, all data and connection information of subscriptions is lost. After
restarting the server, the client needs to re-establish the connection and set up the
subscriptions again.
Connection abort
If a connection between the CP as UA server and an OPC UA client aborts, the session is
retained according to the OPC specification.
Deadband
When monitoring items for the "DataChangeFilter" the OPC UA server of the CP uses the
parameter type "AbsoluteDeadband".
Speed of the data transfer
Note
Speed of the data transfer
Where possible read and write tags in in data blocks block by block per DB to achieve a
higher speed.
CP 443-1 OPC UA
Operating Instructions, 01/2017, C79000-G8976-C427-02
Configuration and operation
4.9 Properties of the OPC UA server
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