Typically, an OPC Server program is used as a middle-man between LabVIEW and Industrial Hardware, such as a WAGO module. You can use the DataSocket functions in LabVIEW to "talk" to the OPC Server, and the OPC Server program handles communication with the hardware. Their are many added benefits of this approach, including:
1) Ease-of-use : Implementing this, and writing the code from the LabVIEW side, tends to be quick and easy.
2) Open Industry Standard : Using OPC Servers to handle communication with industrial hardware is a common, open-standard approach in industry.
3) Network Connectivity : The OPC Server allows any computer on a computer network to read/write to the OPC Server, and therefore the hardware. This is very powerful - you could have mul
tiple LabVIEW programs on multiple different computers monitoring/controlling your hardware if desired - again, this is fairly easy to implement with OPC.
For more information on OPC, I would recommend the following KB as a must-read:
"Driver for communicating with PLCs, RTUs, and other Industrial Hardware":
http://digital.ni.com/public.nsf/3efedde4322fef19862567740067f3cc/13ee0a9e2c43f0db86256a6100722651?OpenDocument
As for the OPC Server, National Instruments sells a package called "IA OPC Servers" that does contain on OpenModbus/TCP Protocol OPC Server. The KB I reference above will contain more info.
Regards,
Greg
