I need to do some HMI and data logging with a PLC so I have been searching for tools for VB programmers to program OPC. The automation wrapper seems like way too much trouble for me, it's painfully slow to get anything developed, and I'm having trouble managing unexpected OPC server shutdowns, resource leaks, etc. I need something easy and robust. Is that too much to ask?

I've been looking in google and depending on the keywords I use I find a new product each time. So far I've whittled what I've found down to the following, all of which are Active-X based products: Softing, OPCWare, Software Toolbox, Consolitech, ICONICS.

Consolitech looks like a student project (I'd award the student a fail), not a software product - are they serious? ICONICS don't have anything other than guages etc, great for some HMI, but not all, plus there are plenty of better options for guages. And what about reading and writing some real I/O - like a few hundred values to a database? ICONICS can't do that. Plus it's very, very expensive. Softing looks very professional but seems too difficult to use for my application. Software toolbox is simple to use and is very well presented and documented - it's great for what it does but unfortunately that isn't a whole lot.

The good news is that OPCWare is a great product for what I need - it took a little time to get used to but with a leap of faith I got it going exactly the way I wanted. Are there any others out there or should I stick with OPCWare? Is it definitely the best option available? What do other people consider to be the market leader and why?

 

You want a cheap solution or a ready made tested solution...

?? What PLC are you using
?? What communications ( Ethernet)

It pays to buy an industrial type ethernet card for your PC cause it usualy has an OPC server ( and examples.

Cheap solution is to communicate to the PLC via UDP and let your VB or Delphi program send to stuff to a database ( UDP and Database comes as ready made components) With a few basic checks on PC and PLC side it can be made quite robust ( ie losing comms to PLC/database , actions to take etc)

Ready made stuff = scada package (ex WinCC from Siemens)gives you Gauges tanks etc , gives you OPC ,ODBC connectivity etc but comes at a price)

Somehow ... I think that OPC is a buzz word and not always needed

Greetings

Eric

 

You didn't say what language you use but the automation wrapper pretty much doesn't work with any of the .NET languages.

I have made an OPC client application using C# and I tried out a few different commercial controls but ended up using Advosol's OPCDA.NET (www.advosol.com). It's cheap compared to the other ones and works great.

Anyway. The 2 sites to check out above others are:

www.opcfoundation.org
www.opcconnect.com

 

Just because I choose not to pay exorbitant license fees doesn't mean it is a "cheap" solution (I am assuming you are using the word "cheap" in the derogatory sense, and that anything that is "cheap" is practically worthless). On the other hand, if you mean "cheap" is low cost but fantastic value, like the low cost airlines that enable us all to fly without being ripped off, then yes, my solutions are cheap.

Plenty of opc-based solutions are ready made tested solutions... for example the stuff we do with VB6

You claim the following equation:
Ready made stuff = scada package

Rubbish...
Ready made stuff <> scada package;
Ready made stuff = 3 million VB6 programmers plus millions and millions of lines of code and components on the net for free or for a low cost;

I am using VB6 with guages, tanks, OPC, ODBC, plus all the rest that VB6 and ActiveX can give me...much better than WinCC or any other straight-jacketed rip-off HMI/SCADA "solutions".

 

Iconics' Genesis can easily write hundreds of values to a database. We have several projects doing this... Apart from the gauges, you have all the graphics, alarm capture/detection and display/logging to database or printer, trend logging to database and display, reporting, security, data marshalling, database management, OPC servers, plus plenty of troubleshooting tools.

At the rate which most system integrators charge hours (value their time) you wouldn't have to work many ours to reach the cost of Genesis or other HMI. We've had this type of discussion on this list many times. Rolling your
own HMI is not easy.

Jonas Berge
SMAR
===========
[email protected]
www.smar.com
Learn fieldbus and industrial Ethernet at your own pace:
www.isa.org/fieldbuses

 

strongly suggest goiong to Software Toolbox and checking out the Industrial Gadgets as well as PLC comms ActiveX components also vhiautomation has comms as does Parajit controls where OPC servers fall down is the cost per node. but thay are easy also check out CyberLogic for OPC drivers - great performance

Cheers from: Jeremy Pollard, CET The Caring Canuckian!
http://www.tsuonline.com
Control Design www.controldesign.com
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PLCopen North America - [email protected]
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Thank you all for your comments.

Jonas Berge, Iconics Genesis is HMI/SCADA, which is not the product I was referring to I may not have made this clear. I know all the SCADA packages have more stuff apart from opc client. My post was about writing an OPC client application with VB6, and I was not looking for a SCADA package, I was looking for something like an activeX or other DLL that I could use instead of the OPC automation wrapper. I had looked at Iconics OPC active-x toolworks (I think that's what it's called). That is the one I found unsuitable because you have to be a C++ programmer to create some activex that you can then use in VB. Plus it was very expensive.

I have settled on the opcware toolkit, it gives me a platform to build opc into my Visual Basic apps, without getting tied into a SCADA package. It does OPC but also shows me how to log the opc data to a database like SQL server. I use other components for the instrumentation and other mimics on screen and OPCWare connects with all of those.

Jeremy Pollard, I chose OPC over DDE and other PLC comms ActiveX components such as vhiautomation and Parajit controls as OPC is clearly a superior, more evolved and more open technology. With OPC you can connect to a PLC or serial device over the network without adding serial-ethernet converter hardware, you can also perform numerous simultaneous connections to the PLC, etc. as the OPC driver can be shared, whereas a driver like vhmi needs to be run in process and cannot be shared.

I understand your point about opc servers carrying runtime costs but that's the trade off we have made - on the plus side there is no runtime cost for the opcware.