Noob guide to OPC: how to write a C# Hello World client?

Question

Here is my situation:

We have a software that is used to monitor solar power plants developed. I have to introduce OPC as a new way to acquire data from the physical devices themselves, so that's why I ended up trying to learn about OPC, which so far is being frustrating.

I have installed the Matrikon simulator and using the Matrikon explorer I can see that data is being simulated. What I need now is to create a very basic proof of concept that I can connect to it and print something using C#. As I understand it, I have to use some proprietary API/SDK. I'm only testing things so I don't want to commit to a proprietary way to do things right now. Wasn't OPC created to exactly avoid that?

Is there a simple Opensource DLL that I can use to connect to the OPC server, that supports DA, HDA and AE, allowing me to work without worrying about vendors/sdks?

To add to the confusion I have found OPC Xi and OPC UA.... and I haven't found a tutorial from ground zero up, which is what I'm looking for.

Answer 1

I recommend you use the newest flavor of OPC, OPC UA.

You can build a simple HMI app in C# using these free tools:

1.Microsoft Visual Studio Express 2013 for Windows Desktop available from: http://www.microsoft.com/visualstudio/eng/products/visual-studio-express-for-windows-desktop.

2.The latest source from this site: https://github.com/convertersystems/opc-ua-samples

With this kit you can: Browse OPC UA servers directly from the Visual Studio IDE. Drag and drop the variable nodes to create a data subscription. Use bindings to animate your UI control's properties from the subscription's data values.

Check out the sample application 'Workstation'.

Answer 2

First you need to know which OPC you want to use.

• "Classical OPC" DA/HDA and A&E based on Windows COM/DCOM
• OPC XML/DA, DA as a web service but with some limited performance.
• OPC UA, the last specification allowing you to implement it on non Windows platform and merging DA, HDA and A&E.

After that, you could choose the language you want to use and so use some SDK free or not.

One good website for OPC : http://www.opcconnect.com/source.php has lists of Toolkits you could use.

Answer 3

Providing you with a tutorial... but a little bit of information first:

OPC is everything but open (in an open source way)... the OPC foundation has specified a lot of things to standardize the way automation can communicate - on top of which you could build your own stack. Be warned, the stuf is HUGE(!). So to ease the workload a little, there is a hand full of companies providing you with stacks for different programming languages. Matrikon, Prosys, Unified Automation to name some of them.

However to connect to a demoserver you need to implement a provider and do still need a stack providing you with the basic functionality and to download such a stack, your company must register with the supplier. There is no way round I'm afraid. However there were OpenSource projects: http://www.openopcua.org/ never tried the code though.

BUT just to prove the usefulness check this tutorial http://doc.unifiedautomation.com/

And a book written by the company owner of UA (maybe your company has "Springerlink" access?) http://www.springer.com/computer/information+systems+and+applications/book/978-3-540-68898-3