07-20-2010 03:03 AM
Hello,
I'd like to communicate between LabVIEW (CompactRIO) and the S7-300 PLC.
Which is the protocol NI recommend to use?
I read, that TCP/IP over OPC and profibus work fine. Maybe MPI or Modbus, too.
But I would favor a cheaper solution like the communication directly over TCP/IP. The problem is in my opinion, that Siemens modified the TCP/IP protocol and the protocol itself is not public. I found an example library at ni.com but this was build by using reverse engineering. And I'm not sure, if such a library would work reliable.
I know this topic is interesting for many people, but I could not find a general recommendation here in the forums.
Regards
03-17-2014 10:53 PM
Dear Matt!
I have to say that I did not experience any problems with the code from MarcoPolo5.
Do it !
03-24-2014 11:04 AM
I have direct experience using the NI OPC servers to talk to Siemens S7-300 PLCs, and it's by far the easiest way I've found to communicate. There may be 'less expensive' options out of the box, but from purely a development standpoint, it's very fast and easy to get working.