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Is SAP PCo able to manage the several values sent in one notification by OPC UA server?

duruptse
Explorer
0 Kudos

Hello community

I'm trying to retrieve in one OPC UA client agent all the values sent by an OPC UA server (Siemens PLC) in one notification

Indeed, OPC UA monitored parameters queue size define the number of values sent by server in one event. However, If I define a destination simulation, the xml files are generated with only one value, at the cadence of the Event Interval defined, despite that server is sending event with several values (tested with UAExpert Data logger)

so I wonder if SAP PCo is able to manage those several values sent in one event by OPC UA server?

Thanks for helping

Sebastien

Accepted Solutions (0)

Answers (4)

Answers (4)

Kevin_Hunter
Employee
Employee

Yes it can.

If you subscribe to all the tags to want to monitor then go to your notification configuration and select the output tab you will find an Icon at the bottom of the screen that looks like two gear wheels (Generate Expressions) , press this and it will automatically add all the tags to a single message. You can also do it manually.

Hope this helps

Kevin

duruptse
Explorer
0 Kudos

Kevin

I fully understood what you described. My concern is related to the changes of values during the publishing interval enqueued by server

Here some snapshots of UAexpert (free OPC UA client) where the publishing interval is set at 1000ms, 100ms and queue size= 5 and Siemens PLC as OPC server

OPC Server publishes every 1000ms a queue of 5 values

UAexpert is able to retrieve all enqueued values published by server every 1000ms, and I would like to know if there is a chance that Pco can have a similar behaviour, seems that only last value of the queue is usable in Pco

Kevin_Hunter
Employee
Employee
0 Kudos

As long as all the data is available when PCo samples the data then yes it will show all the values.

Here is an example.

I have multiple tags available in an OPC UA server (this is KepServerEX)

I created an agent instance and subscribed to all of these tags

I then created a notification and added all the subscribed tags to the output

I then configured the destination as a simulator.

I started the agent and manually changed a tag in KepserverEX

And it created the following notification in the simulator

You can see from the XML that all the values have been written in one message.

Hope this helps

Thanks

Kevin

duruptse
Explorer
0 Kudos

Hello Kevin and thanks for answering

I spoke about the several values present in the queue of OPC UA message: server is managing a sample interval, a publishing interval and a queue size : so if during one publishing interval, the sample detects changes on values, it fills the queue with those values and publish them to the client

I would like to know if I'm able to retrieve in one shot all values (for one monitored item) present in this queue

Thanks again

Sebastien