Siemens SIMATIC ET 200AL System Manual page 1474

8. Using drag-and-drop, move the "UA_ReadList" instruction into the program editor.
Select the "Multi-instance" call option.
Click the toolbox symbol (LAD and FBD) or the small green box below the instance name
(STL and SCL) if the editor is not already open.
Select the client interface that you want to use. The example uses the "ProductionLine"
client interface.
Under "Data access > Read/Writelist" select the read list that you want to use (in the
example the "Product" read list).
STEP 7 now automatically interconnects all parameters of the "OPC_UA_ReadList"
instruction.
If you want to write data to an OPC UA server, use the "OPC_UA_Write" instruction and
select the list of tags you want to send to the server under "Data access > Writelist"
("ProductionStatus" write list in the example).
9. If you use different read lists or write lists as program-controlled lists in your user program,
move the "UA_NodeReleaseHandleList" instruction to the program editor using drag-and-
drop operation.
Select the client interface that you want to use.
Now select a read list or write list that you want to release: Only release read or write lists
that you rarely use, since re-registering is time-consuming.
Then, repeat the steps starting with step 7 with the "UA_NodeGetHandleList" instruction.
10. Using drag-and-drop, move the "UA_Disconnect" instruction into the program editor.
Select the "Multi-instance" call option.
Click the toolbox symbol (LAD and FBD) or the small green box below the instance name
(STL and SCL) if the editor is not already open.
Select the client interface that you want to use. The example uses the "ProductionLine"
client interface.
STEP 7 now automatically interconnects all parameters of the "OPC_UA_Disconnect"
instruction.
Communication
Function Manual, 05/2021, A5E03735815-AJ
9.4 Using the S7-1500 CPU as an OPC UA client
OPC UA communication
353