Allen Bradley Micrologics 1100 Ethernet OPC

We have a new project for an Automated Hydroponics. We need filling several tanks with nutrient and water plus schedule irrigation cycles and monitor pump flow; we are using seven Allen Bradley Micrologics 1100 to monitor and control.

We must design a custom HMI using the new Visual Basic 2005 communicating with all PLC in the seven Greenhouses; all devices connected to an Ethernet switch.


Could someone let us know of an Ethernet OPC that will connect the HMI to these PLCs. We are looking for a good compatibility with the new Visual Basic 2005.

Thanks

piscis,

Green houses are quite impressive operations these days. I have a friend in Austria, that runs greenhouses, and was impressed when we toured his farm. Everything was controlled.

I wish I could help, but my experiance is more around DDE than OPC. One question, though. Have you looked at RSView, or Wonderware? Both are great products, and make the HMI much easier. View supports VB routines if I remember right. Just a thought.

Rockwell's RSLinx Professional can be used as an OPC server for multiple PLC's.
You can also check out http://www.kepware.com/ and http://www.softwaretoolbox.com/Prod_Services/OPC/OPCServers/opcservers.html
for other OPC Servers compatable with AB PLC's.

plchacker said:

piscis,

Green houses are quite impressive operations these days. I have a friend in Austria, that runs greenhouses, and was impressed when we toured his farm. Everything was controlled.

I wish I could help, but my experiance is more around DDE than OPC. One question, though. Have you looked at RSView, or Wonderware? Both are great products, and make the HMI much easier. View supports VB routines if I remember right. Just a thought.

Click to expand...

RSLinx includes a purpose built OPC server for Allen-Bradly controllers. However, the lite version that comes with RSLogix does not include this functionality.

You would need one of the following versions: OEM, SDK, Professional, or Gateway.

Edit: The SDK (software developer kit) version looks like it is specifically what you would need. It includes OPC Automation Interface Documentation and Samples and Tech support for building VB OPC clients.

Just a small comment:
RSLinx OEM is quite a bit less expensive than RSLinx Pro and will probably be enough.

By the way, piscis are you counting programming the OPC stuff in VB yourself, or are you looking for a wrapper of some kind ?
www.opcware.com has a relatively inexpensive kit that should work with both regular VB and VB.net.
There are other OPC kits out there. That is just the one that I looked at the last time. Dont know if it is as good as its sales pitch says.

jimbo3123 said:

RSLinx includes a purpose built OPC server for Allen-Bradly controllers. However, the lite version that comes with RSLogix does not include this functionality.

You would need one of the following versions: OEM, SDK, Professional, or Gateway.

Edit: The SDK (software developer kit) version looks like it is specifically what you would need. It includes OPC Automation Interface Documentation and Samples and Tech support for building VB OPC clients.

Click to expand...

I haven't seen the OEM ver of Linx. I have seen SDK. I don't do to much VB or C myself, so it was pretty much over my head. I understood Linx, the OEM was a VB/C programmer. Between us we were able to get CLX and his PC based system to work. This was not a HMI though. It was more like DCS than anything else. This was a true test of willpower. We won.

I have always used Pro for DDE to spreadsheets and Access dbs.

Thanks for the info on OPC. I may have to learn it pretty soon.

I haven't had a chance to play with the Micrologix 1100s built in web server much but it is very possible that you could write VB code to make HTTP request and bypass the OPC completely.

I do this with the 1756-EWEB currently. I didn't think much of the 1100s Web Server so I haven't bothered working with it much. I will try to play with this next week. Maybe the Web Server does have a use.

This would only work with the 1100. It would not work with the 1000, 1200, or 1500.

The reason I’m using Visual Basic 2005 is basically licensing cost. I am planning to use the VB custom design HMI with several greenhouses. Wonderware and RSview both are too expensive for this application.



As far a using RSLink as an OPC server, when I spoke to the AB reps about it I was informed that only one PC can be connected to the HMI. If you would like other PC to access, the HMI within the network you must have to pay another license fee of $800 per EACH PC connected.



Excessively costly comparing to the amazing power and the low cost of VB2005, go figure I only spent $800 for VB professional version.



I’m planning to design and program only the HMI, I’m leaving all OPC communications between the PC and all the PLC to the professionals.



Thanks to all of you.



I got this email from Kepware.



“All of your drivers are tested with physical devices. Yes we have tested the driver an the following Example using the OPC DA 2.0 Automation Wrapper has been tested with VB.Net 2005.




The .net examples can be downloaded from the following Link:
http://www.kepware.com/Temp/Simple_VB_dot_Net_OPC.zip




The zip file when extracted will create a project folder with an Install folder and bin folder beneath. The install folder contains the .Net enabled OPC Automation DLL. You will need to read the Readme.txt file to install it the DLL in the proper location.”

TWControls:

Could you please post your results as soon as you have them. The idea of using HTTP request and bypass the OPC completely sounds very interesting I have not idea you could do this.

What version of VB are you using?

I'm using VB 2002 so shouldn't be a problem with 2005.

It is possible. I played with it some. Working on some code to parse the data. The only catch I have ran into so far is the data files must be continuous. If you use N21 and you next data file is N23, adding data file N22 will mess it up so you must atleast have N22 in there with a size of 1 for a place marker. My method is crude right now though so I may be a able to come up with a way to do this better. In fact I know there is a better way. Right now I am just streaming the normal HTML data to VB

If you want to start playing with it stream
IPAddress/dataview.htm?offset=0&format=0 into VB. This is your outputs. Start playing with parsing it. I am going to try to see if I can find a way similar to the EWEB to do it. If I don't find a way in a few days I will work on refining this method more.

Well done for having a crack at it...and I can understand your motives. All I can suggest is that you may find developing a complete and robust solution more time consuming than you expect...this is a common experience of those of us who have attempted the task.

By all means don't let me put you off if your time is not the issue here, but it is only reasonable to suggest that the commercial products do sell because they do represent good value. (Comparing them to the cost of VB2005 is not really apples with apples....the dollar volumes sold of that product would be literally hundreds of times higher than OPC drivers for PLC systems.)

(PS If you could get hold an RSLinx or Kepware driver as a demo install from someone, it might give you a feel for the full feature set they offer.)

Actually it shouldn't be hard to parse the data even with the crude method.

Yes, I agree good software does help but it can also hurt.

Off topic example. We used to use RsLinx and VB to create an interface so machine information could be used from any computer. We had to load a program on every computer to interface with the VB code on the RsLinx computer to view the information. Everytime we made a change we had to go to each computer to load the updated software. We converted to an EWEB module and a Web Based interface. This way when changes were made to the web files, the next time a user loads the web page, the updated version is seen. We then use VB code to pull the data off of the EWEB through XML to log to our production database. We have found that this is a much easier method. On of the big advantages is that it required not training on how to use the interface, if you can use a web browser then you know all you need to know.

It would also help if Rockwell would release some samples using the OPC method instead of having you purchase SDK. It is not hard at all but it is very intemidating without some sample code. Another alternative would be to use the DDE method but this requires VB 6.0

If repeat deployment costs are an issue, I'd go with the InGear ActiveX and its one time cost. I've got about 7-8 years use out of my one-time purchase; paid for itself many times over.

http://www.ingearactivex.com/html/ab_ordering.html

Something new to look at would FactoryPMI from Inductive Automation, it is a simple HMI builder that can link up to any number of PLC's using the OPC protocal for a flate rate. For the Micrologics 1100 I would recommend Kepware, I have had some diffculties using RSLinx.

We had a intern write a security app over the summer with VB.Net. It links direct to a RedLion via KepWare OPC. We also use KepWare in our plant automation, and it works very well with unlimited connections. It has a one time cost of about $800.