OPC data from SIS (800XA) to DCS(Freelance) lag time
I work for a project which contain SIS with PM865 controller and DCS with AC900F controller .
the problem is the values transferred from SIS to DCS via OPC take much time so when navigating the digivis screens which have values from SIS take much time to recall the data .
so I'm asking about the reason ??
the problem is the values transferred from SIS to DCS via OPC take much time so when navigating the digivis screens which have values from SIS take much time to recall the data .
so I'm asking about the reason ??
Asked 1 year ago
Answers
0
I assume Digivis is OPC client to AC 800M OPC Server with no intermediate tunnels, etc?
Have you tried connecting a 3rd party OPC client directly to the AC 800M OPC server - do you see a lag to add items and get updated values there too?
The AC 800M OPC Server panel (in v6.1 the panel has a new design, but I believe you have 6.0 or older) contain some tools with which you can verify the Actual vs Requested update rates (mark a controller on the OPC DA tab, then select Update Rate from the menu). The actual rate should not deviate too much from the requested rate. If the fast group uses 500 ms (default) the actual rate should be within 500 +/- 10%. If you see more deviation, the controller is likely overloaded or not task tuned.
The Control Builder M have tools with which you can view the Task Load and execution. Ensure you have 20 ms or more Offset between tasks.
By setting the OPCDADEBUGPRINT system variable to TRUE, the OPC server will output OPC function calls to the session.log; this way you can spot if your HMI is posting unexpected calls, e.g. heavy writes, etc. that may saturate the OPC server. Also, you should ensure the HMI is operating in the asynchronous domain of OPC. Don't forget to reset the variable back to FALSE, or else the log file will eventually flood the disk.
Ultimately, file a support case with your regional ABB support center.
Have you tried connecting a 3rd party OPC client directly to the AC 800M OPC server - do you see a lag to add items and get updated values there too?
The AC 800M OPC Server panel (in v6.1 the panel has a new design, but I believe you have 6.0 or older) contain some tools with which you can verify the Actual vs Requested update rates (mark a controller on the OPC DA tab, then select Update Rate from the menu). The actual rate should not deviate too much from the requested rate. If the fast group uses 500 ms (default) the actual rate should be within 500 +/- 10%. If you see more deviation, the controller is likely overloaded or not task tuned.
The Control Builder M have tools with which you can view the Task Load and execution. Ensure you have 20 ms or more Offset between tasks.
By setting the OPCDADEBUGPRINT system variable to TRUE, the OPC server will output OPC function calls to the session.log; this way you can spot if your HMI is posting unexpected calls, e.g. heavy writes, etc. that may saturate the OPC server. Also, you should ensure the HMI is operating in the asynchronous domain of OPC. Don't forget to reset the variable back to FALSE, or else the log file will eventually flood the disk.
Ultimately, file a support case with your regional ABB support center.
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