Can I connect to an OPC server from the Real time target and fetch field data

[rpula]

Hi

My question was to know if there was a way to connect to an OPC server from the RT target (RIO) and fetch data. After doing some reading, I found that it is not possible. Let me then ask a question related to my project.

Iam building a monitoring application for a plant (no control). For this I need data from the DCS (Emerson DeltaV) to make the calcualtions. I could use a host PC with DSC installed and make it act as an OPC client, collect data from OPC server and pass it over to RT target for monitoring calcualtions. But in this case, if the host PC fails, having a RT target (cRIO) makes no sense.

I was looking at Industrial panel PC as an alternative instead of using (cRIO and HMI combination). However, it is like a normal windows based PC connected to the internet, which may fail due to virus problems. Iam looking for an alternative which has the ruggedness of a cRIO.

Has anyone had a similar experience? Is there an option where I can use cRIO but without host pc as OPC client. Any ideas on this will be appreciated.

Thanks

[Pakman]

Hi rpula,

As pointed out by Gerardo in this post, you cannot make the cRIO an OPC server/client due to OPC's Windows only communication mechanism (COM).  

Does your DCS support any other communication protocols?  If you're not sure, then could you please point me to an online manual?  Thanks, and have a good night!

[rpula]

Here are some of the links I found for DeltaV DCS.

http://easydeltav.com/bol/MasterBOL.htm

http://www.easydeltav.com/repository/about/dvsystemoverview.pdf

http://www.easydeltav.com/pd/PDS_SerialIntSeries2.pdf

Do you think there is a workound for my problem?

[Pakman]

Hi rpula,

Looking over the documentation, it seems like the Emerson DeltaV simply acquires data much like our cRIO or Compact FieldPoint.  What kind of calculations is the Emerson making?  If you don't already have the DCS, you can probably just purchase a cRIO or cFP and store the data locally, avoiding communication between devices altogether.  Otherwise, if you already have the DCS...

From this discussion and page 2 of your third link, it appears that the DeltaV supports at least Modbus over RS232 serial.  If that's true, then you can communicate to a cRIO controller via serial Modbus. 

One of the related links at the bottom points to the DevZone article Connect LabVIEW to Any Industrial Network and PLC: Modbus TCP and Modbus Serial.  It states that if you have LabVIEW Real-Time and LabVIEW DSC, you have the ability to easily make Modbus connections via Modbus I/O servers.  Otherwise, you can download the free LabVIEW Modbus library.  Either way, this is one potential solution.  Maybe your DeltaV supports Ethernet like the second link suggests?

Please let me know if you have any questions!