OPC via Visual Basic

[tommyrush]

Hello

Does any one know how to communicate with the OPC Server via Visual basic. Has moeller released any example code? Would appreciate some help?

Regards

Tommy

[befu]

Hello Tommy,

we have done a few tests with the easy OPC server and Visual Basic, using the automation interface (opcdaauto.dll) provided by the OPC foundation. Normally this DLL is distributed by the vendors of OPC related products. The S40 OPC server from Moeller has the opcdaauto.dll in its installation package.

Unfortunately the OPC Toolkit from Softing, which was used to build the easy OPC server, doesn't contain this DLL. But it is usable, if it's installed with another server package, e.g. the S40 OPC server. In this case a small example is available.

We considered to deliver this DLL with the easy OPC server, but to avoid legal problems, we decided not to include the opcdaauto.dll from the S40 OPC server (build with a toolkit from another vendor) in the installation package of the easy OPC server.

I would recommend you to use an commercial standard ActiveX control, provided by many vendors. The Softing AG (www.softing.com) offers an "OPC Toolbox ActivX", which allows you to develop VB client applications with no additional runtime licence costs for your customers. You can also try to find other vendors, simply ask "Google"!

I think, our forum member RogerP is interested in the same topic, maybe you can send him a PM and he can give you some hints too!

Best regards

Bernhard Funk

[RogerP]

Tommy.

I've just read your post about VB. I had a quick look at using VB6 and the opcdaauto.dll. However, it is reasonably involved, and requires a fair bit of programming. Alternatively, take a look at:

www.kineticaRT.co.uk

They do VB.net controls allowing very easy connection to OPC servers - not just Moellers - and display and control components. The OPC connection componenet is not a free download, about £14, but the control and display components are available as unrestricted demo versions for full evaluation.

I have now got some working, and they really do look good.

If you are to stay with VB6, they do offer activex controls, but not on the website. You will have to contact them to obtain them.

I think the component / activex way is a lot easier than coding yourself.

Regards,

Roger Perkins.

[tommyrush]

Roger, Berhard

Thank-you for your reply's

I have had a look at the Kinetica web site. There product looks ver good. Roger, can you display the programme in the easy graphically with the Kinettica components? How did you find the software to use?

Regards

Tommy

[RogerP]

Tommy.

It is full programming that you have to do. I'm not a professional VB programmer, but have a fair bit of experience.

You may recall I'm doing a factory BMS type system, for space heating, lighting, compressed air etc. The KineticaRT components I use display temperature set points for Easy analogue comparators. Also, you can display numeric values such as times, or counters, and digital I/O and markers in buttons or indicators. It's really like a virtual control panel on the PC.

It's not the Easy program that you visualise, but the data in the Easy relays.

Hope thats some use.

Roger.

[tommyrush]

Roger

Thanks for your reply, Sounds like we work in the same kind of industry, I use the easy's for my HVAC applications and am tring to use them for BMS, just as you are. I too have very little programming experience in visual basic, but am looking to do the same as you.

Once i make some progress with the OPC, i will post some of my examples to you, could help you along with your project?

Best Regards

Tommy

[swami]

If you are using VB then why do you want to use OPC.
Take a look at the support on http://www.moellerusa.net and you can find demo's for 400/600 and 800/MFD directly controlled from within VB and Exell (VBA).