Siemens 6EP4131-0GB00-0AY0, Equipment Manual

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Engineering and remote access
3.10 OPC UA server
SITOP UPS1600 / BAT1600 / UPS1100
Equipment Manual, 07.2021, A5E37775406-11-76
163
Addressing OPC UA parameters
Addressing parameters in the OPC UA Server of the SITOP UPS1600 is based on the
unchanging BrowsePath (complete path made up of BrowseNames to a specific OPC UA
parameter; i.e. "BrowseName1.BrowseName2.BrowseName3"; for example
"UPS1600.ActualBufferState.BufferReady") - and on the specific BrowsePath dynamically
assigned NodeId (for example "ns=3;i=100017").
Please note that the link between BrowsePath and NodeId is re-established at each system
start and as a consequence can be variable. However, the link relationships between
BrowsePath and NodeId only change within the context of configuration changes (e.g. when
adding or removing system modules) or after firmware updates.
As a consequence it is recommended that OPC UA parameters are always addressed based on
the BrowsePath that does not change - or to automatically determine the NodeId of each
OPC UA parameter at each system start.
Subscribe to a node
The actual values of a subscribed node are permanently displayed in area "Data Access View".
To subscribe to a node, drag the appropriate node from area "Address Space" - and drop into
area "Data Access View".
A subscription can only be made to nodes of NodeClass "Variable".
3.10.5.2 Changing the value of a node
Write access operations to values are not permitted in order to avoid making undesirable
changes.
Write access is made possible by calling method "InitLock". After 10 seconds, access is
automatically blocked again.