Is it possible to collect the raw RSLinx data via some programming interface? I want to build a web page with some plant data and while I can do what I want through SCADA software add-in packages, they are very expensive and for what I want to do it isn't worth it.
Anyone done anything similar?

If you have a version of Linx other than Lite, you can use DDE and Excel. There are examples in the download section.

Try FactorySQL. It'll synch your PLC to an SQL database enabling status indication or control via a web page. Your web page need only communicate with the database. I don't mind helping you get started if you'd like.

Thanks but that product is pretty pricey too (~$4000 US) . Not in the league of Intellution and others to be sure, but still not within my reach. I'm looking for a way to do this with code which will only cost my time with maybe a OCX or two.

What processor are you wishing to do this with or will there be various processors

Building on what Ken says you can also use VB or VC and DDE / OPC for larger scale collection then excel.

(30) PLC-5's', (4) CLX5000's and I believe there will be a set of 10 micrologix 1000 coming in soon. Not certain about those yet.

I came across something called TOPserver that isn't terribly expensive (~$800) but not sure how accessable it is yet. Also not clear how it gets it's data, no mention of RSLinx so far.



That leads me back to TOPserver. Sound like that might be an answer. I need something to read my rs-485 particle counters in a way that will allow me to put them in SCADA anyway, so perhaps that will kill two birds at once.

You need to look to see if Topserver can make DDE or OPC request. Or perhaps execute VB code. That is how it will use RsLinx to communicate. PLC > RsLinx > Topserver

Do you already have a version of RsLinx?

Yes, RSLinx Pro 2.42 (I think). But if TOPserver doesn't need it, thats better. It sure looks like it doesn't. Unles you are about to reveal a top secret, eyes only way to use RSLinx for this?

You got a link for TopServer? I'm having trouble finding it

here you are http://www.toolboxopc.com/
I started to think that the price was for the driver only and not the "server" But I don't see a "server" listed anywhere else.

Unless I'm missing something, this is pretty much the same as RsLinx. It is not a web server, you'll still have to do that part

Oh I realize that it isn't a webserver. But if I can find a method that I can interrogate a database with something like SQL queries or simliar, then I can build the pages myself. But I can't do that to RSLinx.

My thought was that RSLinx only communicates with whatever application knows how to communicate with it, and that data exchange protocol information is proprietary and probably licensed for gobs of money.

I further thought that an OPC server lIke TOPserver and others somehow speaks to the hardware directly (or through drivers that they created) and makes that data available to mortals through a standard interface that can be easily interrogated by multiple methods.

But I have thought lots of things in my lifetime. Not all have been accurate. This might be one of those.

RsLinx is both a OPC server and the older DDE server. No secrets. The DDE is very straight forward. I haven't done a lot with OPC but there are some sample here

Unless I am missing something you're thinking is corrrect. This appears to be an OPC server program which can query your AB PLC for data and serve it up to your OPC compliant application {Excel, SQL, Etc}. ANd TW is correct RSlinx in versions other than lite provides this functionality.

OK, I'll look a bit harder at the RSLinx driver and how to interrogate it. Thanks to all thus far.

You might also look - depending on what you want to do the 1785-ENET and the SLC 5/05 support custom web pages broadcast from the PLC. You might be able to send your data that way.

I was holding back but since Bob mentioned it I have used a single Controllogix processor and a 1756-EWEB to collect data from SLCs, Micrologix, and other Controllogix processors and serve web pages. It could do the same with the PLC5. The initial hardware cost would be high though

Some of the higher end PLC-5's already have the web page server option.

We have the controllogix processors already and we bought one just to experiment with. 1756-EWEB? Thats a module? I'm gonna look into that right now.
I have seen the custom web pages inside the PLC5 but didn't think much about them as it looked like it was only a few lines worth.

What I did with the Controllogix containing the EWEB was used it to gather information from all other processors in the plant. This method was cheaper than making all processors in the plant web enabled

The 1756-EWEB allows for completely customized web pages

I just dl'd the brochure, can it have it's own IP that is different from the controllers IP? I know that some modules in the CLX line can do that. And can that IP be on a different subnet? That may be just what I need. And far easier to get bought.

The book says that it can only get data from it's local chassis, so did you pull the data into the local chassis and then have it serve the page or did I miss something that allows you to pull data from other PLCs ?

You can do CIP request to anywhere you can build a path to. Pretty much this is a Ethernet/IP, Controlnet, or Devicenet device that you can build a path to. This does not include Micrologix, SLC, or PLC5. This is where you would use a processor along with the EWEB

You can only have one IP address per module. But if you are thinking one for the plant and one for the office you could also use a router and assign an ip on your office network to route to an ip which your EWEB is assigned on your plant network.

We actually used 3 ENBTs to communicate with the plant and 1 EWEB with an IP on the plant side and a router connecting to the office as described above.

I like this setup. It is very reliable and doesn't require much maintenance but there is up front hardware cost

One address per module but does it have to be the same subnet as the processor? Can you tell me about what the module cost was? List proce is fine, just getting an idea. I will check with my dist but lots of changes have happened over there and all the knowledgable people left.

You can find any of Rockwell's List Prices HERE

But after reviewing this topic I think we have gotten a little off. You were looking for more writing software and less purchased hardware weren't you?

Yes you are right of course, And the price tag of $2500 for that module puts me right back on track .

Now, getting back to reality, I'm looking for a mostly software solution that I can poke at in my spare time.

Two options to ponder.

Can you initiate a DDE request using a vbscript? vbscripts are executed on the server side so if RsLinx was on your server then it would work IF vbscript can initiate a DDE request

Have your webpage open an Excel file. It can do this without actually opening Excel. Excel will do the DDE request, the parse the data in your web page. Tons of work but cheaper (still $800 or so)

The Excel technique may be what I have to do but I was hoping for a bit better formatting of data as well. If I could use ODBC then I can use ASP scripts and I have some understanding of that process. If I could only interrogate the iFix database directly...
I have some homework ahead of me.

btw on a completely unrelated note, Whats this "WARN 0%" meter mean on my posts? I don't recall seeing that before.

I wouldn't worry about it. If it says 0% then you are fine. MrPLC is a growing forum and this is a new tool that is being tried to help us keep the forum on a professional level.

FactorySQL is $1895, not $4000 and the free trial will run for 2 hours at a time.

Topserver is a rebranded Kepware OPC Server - basically performing the same functionality as RSLinx, which you already have. Kepware makes a good product. RSLinx is a good product. They're pretty similar as far as this application goes.

Ken's suggestion with Excel via a DDE connection to Linx would work for a small, non-critical application. It is not terribly difficult to do. You should know that there is a (stupid) US patent protecting that (#5,038,318). Doing projects like this via Excel is pretty clunky. Think: computer must autologin, macros enabled, spreadsheet autoopen, no user touches the thing. Not exactly the pinnacle of reliability. DDE is old and clunky these days too. An MS service pack among many other things could mess up your app.

If you're familiar with VB programming you can do this for free. The OPC foundation has free sample code to make OPC requests that would work via RSLinx (you said you have a copy of pro). Also look at OPC toolboxes, etc. You might check Sourceforge...I would highly recommend going OPC since you already have RSLinx versus any native AB driver projects you might stumble upon there. You'd really strike it if you can find an LGPL OPC datalogger project. I'll take a look.

My mistake, when I went to the site I just hit "price comparision" thinking that would be the place to find the price compared to other brands. I see I was looking atthe wrong thing and that it is just what you said. Sorry about that.

I thought the same thing about DDE (even a 6 year old software program we use for particle counters didn't recommend DDE back then) but I didn't see many alternatives. (didn't know about a patent! How odd!)
I have some small familiarity with VB and obviously I will have to get more into it anyway so I'll look at some samples to see if it is within my skillset now or will be later. I even have a 1998 disk that says "OPC Server Toolkit from Intelliution" so that's a start. That'll be more fun anyway. Thanks for the correction and advice, All of you.
Time to go pester the OPC foundation folks.

There are several threads that deal with RsLinx and OPC. They might give you a starting point. Search this section

Here is one
http://forums.mrplc.com/index.php?showtopic=9292

Thank you for that too. You guys have been fantastic!

Searches under 4 charactors don't work so well so do a search for visual basic instead of opc. It should grab them all but you will have to sort through them and find the OPC ones

The patent is the most ridiculous thing ever! Someone deserves to get smacked for that one! OPC(DA) is already a pretty old tech - based on MS DCOM, but it's the best (most standard) out there now. They're working on OPC-UA, which will use: XML, web services, security models, etc, etc. The lead OPC guy was one of the Rockwell's top programmers. He's in good with both FactoryTalk and Archestra and some of the better features of both with be integrated into OPC-UA - A non-proprietary standard is a win-win for all.

I'd play with some of the VB or even VBA scripting with OPC. There's lots of examples out there. If you have specific OPC questions I can run them by our programmers and might be of some assistance. I'm not sure if there are any good OPC forums. I'll have to check...

I would appreciate your help more than I can express!

Look for the free software from Ron Gage.

You can use it to directly talk to at least the PLC-5's. There is a similar package out there that handles Ethernet/IP though it isn't nearly as "clean" in terms of reading.

From that you can probably easily build a web page with Python or Ruby on Rails or TurboGears (Python Rails).

Good call Paul. If you're only dealing with one type of PLC a specific package/project would work fine. All those scripting languages he mentioned are relatively easy to use and very powerful. I haven't dealt with the "on rails" versions with the web APIs. Do they support a lot of AJAX? Maybe I'm "old school"...I'm still a fan of PHP.

Waterboy - could you describe what you're trying to accomplish with the project?

If you are familiar with VB you can download VB express here:

http://msdn.microsoft.com/vstudio/express/

Here is an excel spreadsheet from AB using OPC I have also attached the file I have experienced some difficulty with AB's upgrade of their KB lately:

http://domino.automation.rockwell.com/appl...5256AFB0059FE9F
VB forum for help with VB code:

www.codeguru.com

A sample VB.net application from Kepware not sure of any restriction of use but it will give you a good start change the referenced OPC Server to RsiOPCAuto (Rockwell's OPC DLL packaged with RSLinx) and it will work fine as written to display data it does not store the data anywhere:

http://www.kepware.com/Temp/Simple_VB_dot_Net_OPC.zip

I am working on a custom data collector myself right now using Visual Studio 2005 (VB 2005) one note if you try to attempt a custom VB app Micro$oft stopped packing/including DDE with VB.net from it's inception. So DDE is not even an option unless you are going to use VB6 or earlier.

Also watch out this is one project that can grow into a monster.

My collector has an Access Database as the bacbone of the colletor sytem to hold tags, system configurations, etc, as well as real time values. All tranactions are handled by Visual Basic code. It also caches all data collection points in the Access Database waits for positive confirmation of successful transmition to the SQL Server 2005 database before destruction of cached data. Of course if the data you will be collecting is critical you also will need to incorporate caching in your PLC(s), something you may want to include up front.

I guess my point is their is a lot to consider and the cost of a canned system may be cheap compared to the time you will spend on it. In my case their is not one package that can do all we need it to, and do it all well, so we opted for the custom route.

I looked up Ron Gage and his stuff is all Linux. I barely get Windows at this point.

The end result of this project is a web page with whatever info on it that the managers want. They don't need very much and it's not worth putting the SCADA software on thier machine (well, I don't think so now, I might change my mind after trying to make this work;-)) This is an experiment that I will do in my spare time to see what the limitations are. If I am able to read PLC values with a web browser there are many places where thats all that is needed, If I can write to them there are many more.

One of the more interesting issues I am also trying to address is our remote sites. We have ~30 remote stations all linked through radio telemetry. It would be a bonus to see if what the operators see at the plant is what I am sending from the remote site. That could be done with a browser based view that is accessible over a cellular web link.

You're right of course, the canned system is more than likely the cost effective way to go and I can see how this could grow into a huge project with a life of it's own. But I have to try to see how the process works. I don't even need to collect and store anything, I just want to display it in as close to realtime as I can.

I volunteer at a non-profit as a network admin and one of the perks is a premium MSDN subscription, So I have all the tools I need, just not the expertise... yet.
Thanks for the links, I have a lot to digest over what seemed at first to be pretty straightforward.