Remote OPC w/ LV8, IA OPC, citadel

[RegisPhilbin]

We are preparing to write a SCADA system using remote OPC. Since we will have LV8 PDS here in a couple weeks, it seems like a good idea to use that version, instead of 7.1 PDS. Can anyone point me to documentation on setting up remote OPC using the new logos and DSC packaged with LV8? Does the IA OPC server change?

I will most likely use the following components:

• LV8 & DSC8 as the HMI
  
• A remote OPC / data server using the NI IA OPC server (modbus/TCP & DeviceNET w/ NI PCI-DNET card), Citadel DB or other.

I want to install only the minimum software on the server, such as logos, IA, citadel?

What ports does DCOM use for this remote OPC?

The HMI will have the LV runtime to run the executable.

I have already gone through all the DCOM config issues to get the DSC tag engine (on the HMI computer) to launch the remote OPC server using version 7.1, but now I need detailed information on the setup differences between 7.1 and 8.0.

I hope someone can point me in the right direction.

HMI : Windows XP, sp2
Server : Windows 2000 server, sp4

See attached for the proposed network architecture.


Thank you,
Eric Scott

[DimensionFinder]

Hi There: First off, LV DSC 8.0 has changed considerably from 7.1 LabVIEW 8 is an OPC Server by default. For this reason, you will not need IA OPC Server. Second off, there is no tag engines per say. You will configure shared variables instead. LabVIEW 8.0 has a project based architechture. In a project, you can define Shared Variables which can be shared by VIs within the project. Information management is now done via the Shared Variable Engine which communicates with citadel and logs alarms and events. You will define Shared Variables instead of tags in the tag engine. citadel 5.0 and logos will be installed with LabVIEW DSC 8.0. I am not too sure about the port that DCOM uses for OPC. Can you also send me your email address so we can communicate over that? Thanks, Jaideep

[Khalid]

"LabVIEW 8 is an OPC Server by default"

Wasn't LabVIEW-DSC always an OPC Server?  As in, its tags were always exposed as OPC items by default.  I am assuming you mean to say DSC 8.0 now ships with the IA OPC Servers for different PLCs and devices -- is this correct? 

By the way, what option does pure-LabVIEW 8 (i.e., no DSC module) have for communicating with OPC Servers?  Is it the same -- via DataSocket? 

Thanks,

-Khalid

Message Edited by Khalid on 10-10-2005 11:51 PM

[RegisPhilbin]

Thank you for the reply.

Perhaps you can elaborate on the OPC server that ships with LV8 PDS. Is this the PSP engine that I hear about? Can it be used as a standalone server?

What I want to accomplish is to create a modular SCADA based on OPC as a central data exchange. By modular I mean that I am not forced to use labview for the HMI (although I plan to). I could use Measurement Studio, Wonderware, or the like. It just makes OPC read/writes. Same situation with the PLC.

Originally I had considered just using datasocket read/writes to the OPC server, but I like some of the features of DSC, although it does add a level of complexity (and cost). DSC is nice because the data point can be logged automatically without writing code, force initial value, deadband, alarming, MAX interface, etc. BTW - Does DSC 8 use the OPC foundation A&E spec, or is it propietary? (this is more out of curiosity than anything else)

Do you know of any document that discusses setup and configuration of the new logos/PSP/OPC server that I can download? Especially something that details the minimum install requirements on the remote side.

You can contact me at 'first inital last name @axelgaard.com'


Thanks, Eric Scott

[DimensionFinder]

Hi Eric and Khalid:

Its great to see activity on DSC 8 spurring up already. Unfortunately, I can only provide limited information about it. First, because all this documentation will be released when DSC 8 begins to ship, so you all will have access to all of this information very very soon on our website. Second, because, I do not want to inform you of anything incorrectly because of the limited access I myself have to information.

To answer your question Khalid, LabVIEW 7.1 is not an OPC server, DSC is the server. In the case of 8.0, LabVIEW itself is an OPC Server.

After looking at your email again, Eric, I believe you will still need the IA OPC Server or some other OPC Server such as RxLinx. DSC will allow you to communicate with your Modbus device but not with DeviceNet.

The way things work w/ respect to servers in DSC 8 is a bit different. In 7.1 there was an OPC Server and all communication was done via OPC. In 8.0 we have introduced I/0 servers which allow you to communicate in different protocols. For example, there is a Modbus I/O server and an OPC I/O server. I/O Servers expose PSP data items on the network and these items can then be accessed from the address psp://URL.

Again, you will have access to this sort of information and much more once the DSC module is released for shipping.


Hope that helps.

Best Regards,

Jaideep Jhangiani