Siemens SIMATIC S7-1500 Function Manual page 268

Example of an error-free assignment of the structure elements
In the imported node set file (XML export), the structure is defined as follows:
The structure mapped in the read list matches, both in the order and in the assigned data
types, the corresponding nodes of the node set file.
If the structure now changes on the server, for example tagA and tagB are swapped, and the
read list remains the same in the client, the assignment is no longer correct:
● The total length of the data remains the same (only the order has changed)
● The configuration of the structure is different for client and server!
No error message in the case of different structure configuration between client and server
If the structures of client and server do not match, this rule violation will possibly not
generate any error during compilation and also not in runtime.
Make sure not to change the configured assignments for structures in runtime. If required,
reconfigure the assignment in the read and write lists!
Communication
Function Manual, 11/2019, A5E03735815-AH
WARNING
9.4 Using the S7-1500 CPU as an OPC UA client
OPC UA communication
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