OPC server setting

Hi
I`have developed an application client which has shared variables bounded with an OPC server of NI. Sever and Client are on the same machine. My executable works very well.
Now if I want install my executable on a machine that has not the OPC server installed, so I need to change manually the path of the OPC server and of all the shared variable bounded before creating the executable.
Is there any possibility to set the path of the OPC server on the front panel of the application? Any suggestion how can I develop a VI to set this path?
Thanks
Vincenzo

Hi Vincenzo,
I've never tried it, but I guess the "Create&Configure IO Server"-Express-VI should do the job (DSC Module/EngineControl/Variables&IO-Server). It allows you to dynamically setup a connection to an OPC-Server (or other server type).
If you use the "Overwrite if I/O-Server exists"-Option and use the name of your original I/O-Server, all your Shared-Variables connected to that Server should (hopefully) automatically connect to the new OPC-Server.
As I mentioned, I did not try this. So, let me know if it works.
Good luck,
Thomas

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Hi,
I have been using NI DSC and OPC servers (NI and Kepware) to communicate with Allen Bradley Micrologix 1400 PLC (1766-L32BXB). Recently at one site I found that I could access Process values from the PLC correctly (Read Only tags) but could not access the Read Write Tags at all. The latter are addresses to which it should be possible to write Set (i.e., references) values from MMI or PC software. I am able to do so from the MMI not from the PC software. I get communication error message on the MMI and PC, mentioning the PLC address being accessed (e.g. N7:0).
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What is the best way to disable tags in SVE when a OPC server is not available?

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PierreN,
In order to set the timeout value of a Shared Variable, you may Right-Click, and select 'Show Timeout':
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Cheers,
Pcorcs
Patrick Corcoran
Application Engineering Specialist | Control
National Instruments

How to specify Attribute ID in OPC Server DevicenetExplicit

I'm trying to set up an Allen Bradley 842D Devicenet Absolute Encoder
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NIDeviceNetExplicit Example
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Regis

Hi Regis,
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(4) Then you get the alarm message in IA OPC server and get failure message in your OPC client , if you have one started allready, because it reads the item automatically.
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Add an OPC item NIDeviceNetExp1.IID1.UDINT0
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Hope that helps with your problem.
DirkW
Attachments:
DNET to OPC Item.vi ‏44 KB

Error 1101 - Cannot communicate with Experion OPC Server

Hello,
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Have any users found a remedy for this issue?
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Error 1101 occurred at DataSocket Open
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Thanks,
-Brandon

UNABLE TO START NI-OPC SERVER

WHEN START OPC SERVER
Error in NI-OPC: Unable to load driver dll 'c:\Program Files\National Instruments\Shared\ NI O...
PLS HELP..........

Do this as a quick attempt. Under the "OPC Settings" tab there is an option for "Use DCOM configuration utility to set security" ... this is ON by default. Uncheck this box and restart the service.
see this solved thread for more details. Don't hesitate to post back if you still have problems. We are glad to help you.
Mathan

Can't connect to KepWare Enterprise OPC server

I am trying to connect to the Kepware Enterprise OPC server with Server Explorer 2.4.1 but get a message 'The system cannot find the file specified' 0x80070002. I have modified the DCOM setting for XP SP2 as described in the Kepware documentation. Is there a way to resolve this issue?
Thanks
Harry

Hello,
Can you explain exactly how you are attempting to connect to this OPC Server and also any of it's properties that are set in Server Explorer. At what point do you get this message? Have you been able to connect to that OPC Server on that machine, or any machine before?
Cheers
Tom | NIUK

Omron OPC Server with Lookout 5.0

I am trying to set up a Lookout 5.0 application using the OPC Client, connecting to the Omron OPC server, CX ServerOPC. When I add the OPC Client, I find the server on the drop down list, but when I click 'OK' to create the OPC client object, once it connects to the OPC server, Lookout crashes. I get the message that Lookout.exe has encountered a problem and has to close. Has anybody used this server before and seen this problem? Any hints as to what could be incorrect in the client or server settings?

Hi,
What happens if you connect to the Omron OPC server from the National Instruments Server Explorer? Do you access to the OPC items succesfuly in Server Explorer?
Please also check the Tutorial linked below:
http://zone.ni.com/devzone/conceptd.nsf/webmain/B0CC5FE5CBC5727F86256808006AD802?opendocument
Hope this helps.
Best Regards,
Remzi A.
National Instruments

Connecting a Siemens S7-300 PLC to NI OPC Server

As a part of the final year Bachelor Thesis project I and two others are involved with, I have been tasked with setting up an HMI/SCADA system to control level and flow in several water storage tanks. This is to be done locally via a "Operator Panel" and also remotely over the Internet via webbrowser. These storage tanks and control system is placed on a wheeled demonstration model so it can be used in classrooms and auditoriums. As such, I have a Siemens S7-300 PLC and the latest edition of LabVIEW (2009 Professional Ed.) available to me. In order to create a HMI system, we will also acquire the NI DSC module as it should have everything we need (NI OCP is included?).
Since this is a bachelor project and the school is basically paying for everything, we are on a rather strict budget. This means that we currently haven't settled on a solution for the "Operator Panel" since this would be dependent on how the PLC and panel interfaces. What we would like to do for simplicity sake is to use commercial laptop computer with touchscreen capability thus having a low cost "all-in-one" solution, both for local input & control and web publishing capability. Now, most computers today doesn't have serial comports anymore, but rather USB ports.
On the OPC server webpage under the OPC Device Connectivity heading, it is specifically stated "Siemens HMI Adapter for S7-300/400 via Serial with HMI adapter". I assume this refers to the following Siemens product: https://support.automation.siemens.com/WW/llisapi.dll/csfetch/8774263/hmi_adapter_x.pdf?func=cslib.c... (6ES7 972-0CA1X-0XA0).
Does this mean that the OCP server can only use a Serial connection via the HMI adapter for the S7-300 directly? Would it be possible to use a driverless Serial to USB adapter with the HMI adapter, or for example the Siemens CP5711 MPI to USB adapter? If it is not possible to use a USB based solution, We would have to use an older desktop PC with an serial comport or an additional PCI card and that is something we would like to avoid.
Any help on this matter would be highly appreciated.
-- DanJack, NUC Norway
Solved!
Go to Solution.

now this is a problem the PLC S7300 does not support some functions of communication when you want to make a simulation may not be accessible from OPC Server, this by PROFIBUS Siemens USB / MPI + PLC S7300/400 protocol adapter cord
Atom
Certified LabVIEW Associate Developer

NI OPC server vs. KEPDIRECT

I am in the process of setting up an industrial PLC project. I am wanting to use Labview for communication with my Automation Direct PLC system. Automation Direct offers an OPC server KEPDIRECT for $295.00. NI OPC server is quoted at nearly $2,600.00. Money is not a factor in my situation and I want to purchase the best and most efficient server. Can someone explain to me the difference in the two servers (why one is more expensive than the other) and which one is better for working with labview and a PLC. I currently have my system programmed with Automation Directs Direct Soft 5 and Lookout Direct and want to completly switch over to Labview if this makes any difference. Thanks for any input and help.
Solved!
Go to Solution.

Blue Ridge Test, a certified NI Alliance Partner, has successfully implemented a control / monitoring system with LabVIEW which interfaces to networked Automation Direct PLCs through ethernet (ECOM modules) and OPC. If you are interested, we would like to talk with you about your application to see how we might partner together to achieve an elegant, cost effective solution which meets your goals while removing months from your timeline.
If you decide to approach this on your own, there will be configuration challenges (e.g. extracting the correct tags from DirectSOFT 5, setting up OPC, etc.). Before addressing those, though, you may want to think through your programming requirements such as those listed below.
After the setup phase of your project (i.e. configuring hardware & signal conditioning, verifying connectivity, demonstrating various portions in LabVIEW, etc.), you might consider your architecture before moving forward. How will you store your data? How will you view / analyze the data later? Is the architecture readable, scalable, and maintainable? What will happen when you want new features (e.g printing reports, user logins, or controlling other external equipment or processes while saving data and displaying results)? What kind of user interface will you use?
Set yourself up for success long term by thinking about the right architecture today. We frequently have customers whose "simple engineering experiment" grew on them. And, interpreting bad LabVIEW code a year into a project can be a lot like deciphering abstract art (and equally expensive).
Jason B
434-525-7312 x114
Message Edited by Support on 02-10-2009 05:17 PM
Certified LabVIEW Architect
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Separate Views from Implementation for Strict Type Defs

Opc server on compact fieldpoint 2100

Dear all
I am having a bit of trouble on where to start with setting up OPC tags for the customer to view. I have a cFP-2100 in machine which is installed at a power station. It isconnected by ethernet back to a PC in a server room.
All outputs are normally hardwired using an analogue output card to give the values, but this customer has requested I use OPC.
They browse the available OPC servers on the network and find
National Instruments.Variable EngineNational Instruments.Variable Engine.1National Instruments.OPCFieldPointNational Instruments.LookoutOPCServer
Now I can easily change the code to ouput the instruments values to some new shared variables, but how do I go about creating a tag name?
Another question I have the NI devloper suite (NI professional devlopment system) with teh datalogging and supervisory control module 8.2.1 and the labview industrial automation OPC servers 5.1. But i cant find which disk they are on? any ideas?
any help would be much appriciated.
regards,
Chris

Dear Monkins
Please see this webcast of how to create custom tags through our National Instruments LabVIEW software and programmable automation
controllers-to any PLC using the new NI OPC servers
http://zone.ni.com/wv/app/doc/p/id/wv-263
Just as a note, from a performance standpoint, there is no difference between these two
methods when the DataSocket is configured correctly. At run time,
accessing the tags will happen at the same rate and with the exact same
behavior. To configure the DataSocket connection correctly, ensure that
you open and close a connection to your tag only once when reading or
writing from it iteratively, as shown in the following screenshot. From an implementation standpoint, there is an important difference
between the two methods. The shared variable method uses an OPC client
that is built into the shared variable engine. This OPC client is added
by the DSC module. In order to bind shared variables to OPC tags, you
must have the DSC module installed. The DataSocket method uses a
different OPC client built into the DataSocket implementation in
LabVIEW. Because DataSockets are a standard part of LabVIEW, you do not
need any special software modules to access your OPC tags with this
method.
Please see the KB below which describes how to use the OPC server in Labview through using Datasocket.
http://digital.ni.com/public.nsf/websearch/EA15F53DB6FECCA5862567240064DF09?OpenDocument
Also, the below link, describes methods for binding a shared variable to a FP channel; please see method 1 which utilizes this NOT using the DSC module.
http://digital.ni.com/public.nsf/allkb/FA610367EC62574186257118005089F2?OpenDocument
Many thanks for using the NI forums and I look forward to your reply.
Kind regards
David
Applications Engineer
National Instruments UK

OPC Server Remote Connection LabVIEW 8

Hi
Currently I am trying to access a VI with a Shared Variable from a remote computer using an OPC Client. I haven´t succeed on this becasue I cannot find the OPC Server on the Host Computer.
Here is what I am using:
Host Computer:
Windows XP SP2
NI Developer Suite November 2005
LabVIEW 8 with DSC Module.
Remote Computer: The same as above.
Here´s what I have done.
I created a new project with a library that included a Network Published Shared Variable. The VI is quite simple it just generates a number that is written to the Shared Variable. Once the VI was running I opened the Server Explorer on the host computer, browsed My PC and connected to the server Variable.Engine in which I was able to see my shared variable. Then on the Remote Computer I opened the Server Explorer and browsed on my Network Places and when I tried to access the Host Computer I got the following error: "Unable to connect to \\HOST! Make sure that this computer is on the network, has remote administration enabled, and that both computers are running the remote registry service"
I have tried by using the Matrikon OPC Server Explorer and I got the same results. I read many documents that refer tis problem as a DCOM setting because of the firewall fo XP SP2.
Here´s a list of the NI documents I reviewed.
How Can I set up LabVIEW, LabVIEW DSC, and Lookout to work with the windoes XP firewall
URL: http://digital.ni.com/public.nsf/websearch/0D7B86F4B4D19A5E86256F9A006EECB1?OpenDocument
Setting Proper Access for Remote OPC Server When Using National Instruments OPC Clients
URL: http://digital.ni.com/public.nsf/allkb/5C8A90CD57B279F286256C2C006F1EB4
I never got the results I expected. Then I tried the Matrikon OPC Simulation Server and the Matrikon OPC Server Explorer(Client) and I Succesfully connected between Matrikon servers and clients.
My project is based in accesing the LabVIEW OPC server with a generic OPC client but I cannot get the client to connect to the server.
I will apreciate some advice on this issue.
Marcos

Marcos,
If you are using two instances of LabVIEW 8, I would first take the OPC part out and just try viewing Shared Variables on the remote computer. This needs to work. One document to check is the following KB: http://digital.ni.com/public.nsf/websearch/6E37AC5435E44F9F862570D2005FEF25?OpenDocument. I would also make sure the opcenum.exe service is running on both machines.
Once browsing to Shared Variables works, you can test the OPC aspect of the Shared Variable Engine. Server Explorer is an older OPC 2 client, but should work in most cases to browse to OPC Servers -- you'll need to make sure the registry settings on the host computer are set up correctly as per the KB you mentioned, and also make sure to connect to the OPC Server, add a group, and add items manually from within Server Explorer, rather than using the Wizard.
Doug M
Applications Engineer
National Instruments
For those unfamiliar with NBC's The Office, my icon is NOT a picture of me

OPC server setting

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