Siemens PCS 7 and LabVIEW

[BobbyCee]

I am interested in finding out how many of my fellow LAVA lovers have had success interfacing LabVIEW with PCS 7 and what method was used to communicate - i.e. Profibus, OPC, etc

[Tim_S]

I am interested in finding out how many of my fellow LAVA lovers have had success interfacing LabVIEW with PCS 7 and what method was used to communicate - i.e. Profibus, OPC, etc

I've not communicated with the PCS 7, but I've communicated with a couple of different Siemens PLCs. We've used OPC through PROFIBUS (Siemens card) and Ethernet (KepWare) to the PLCs and both worked well. OPC is a process control communication method and not really suitable for machine control (though you can make it work). I assume you're performing process control, though.

Tim

[BobbyCee]

I've not communicated with the PCS 7, but I've communicated with a couple of different Siemens PLCs. We've used OPC through PROFIBUS (Siemens card) and Ethernet (KepWare) to the PLCs and both worked well. OPC is a process control communication method and not really suitable for machine control (though you can make it work). I assume you're performing process control, though.

Tim

Thanks Tim. I do use OPC quite often, but mainly for monitoring tags. As you said, machine control is possible, but it's not a can o' worms that I want to open. I noticed that NI does sell a Profibus card, I just haven't ever heard of anyone using it. My goal would be to connect to the Siemens Profibus Master and use LabVIEW to communicate with the Siemens symbols - I was also curious to find out if using LabVIEW profibus drivers was a cumbersome activity or not.

[Rolf Kalbermatter]

Thanks Tim. I do use OPC quite often, but mainly for monitoring tags. As you said, machine control is possible, but it's not a can o' worms that I want to open. I noticed that NI does sell a Profibus card, I just haven't ever heard of anyone using it. My goal would be to connect to the Siemens Profibus Master and use LabVIEW to communicate with the Siemens symbols - I was also curious to find out if using LabVIEW profibus drivers was a cumbersome activity or not.

Well Siemens usually have its specific way to do things and that often looks a little different than the rest does it. :-)

I've interface with various Siemens PLCs in the past and have used various interfaces to do that. With older S5 we usually went with a direct connection through a serial port which could be either the programmer port or a specific communication processor port. Protocols used there were all Siemens specific and usually developed inhouse on the LabVIEW side, such as AS511, R3964, etc. With the S7 series we did go a few times with Profibus and the actual card used depended mostly on the customer for which it was, as some of them have already a certain standard in house, so that it is not very useful to force them into something else. Cards that we have used where the Profibus card from Comsoft, which is actually what NI is selling as their Profibus hardware, but also interfaces from Hilscher. They all worked but we had of course to develop a VI driver for the Hilscher card first, whereas the Comsoft card came with ready made VIs.

As to accessing the process image of the Siemens hardware, we did not chose to try to do that at all, but instead configured specific datablocks that were used to interchange information between LabVIEW and the Siemens software. It may seem more cumbersome in the beginning, but it is a big advantage if you have a clearly defined interface between the two systems and simply disallow any other interference between the two. It makes debugging so much easier and fingerpointing between the LabVIEW and PLC programmer about who is secretly changing that flag at some point is not an issue.

[zobert]

I am interested in finding out how many of my fellow LAVA lovers have had success interfacing LabVIEW with PCS 7 and what method was used to communicate - i.e. Profibus, OPC, etc

Have used the SST series Profibus cards to make "soft" PLC with LabVIEW for 10+ years. Had to make DLL wrappers but works well. If card software comes with DLL and .h files can have LabVIEW generate DLL wrapper VI's. Also have used OPC via Profibus ethernet CP to communitcate with PLC's.