Wincc 7.4 C# .NET Application

Dear All

Is it possible to have a .net application written in C# to communicate with siemens wincc 7.4 scada explorer?

is so what are the library to use for C#.net need to be install?

Thanks in Advance

sincerely
Brandon

Yes, look up Sharp7.

https://snap7.sourceforge.net/

Sharp7 is good for talking to the PLCs (works best with 300/400, but technically also supports 1200/1500 in legacy mode). Never heard of it talking directly to the HMI, but maybe i guess.


For WinCC 7.4, I'd recommend something like OPC UA. It can be either a client or a server, which should give you flexibility when you integrate an OPC UA library into your C# code.

WinCC 7.XX supports Bsend which Snap7 also does so that might be a possible route even though i have not tried it myself. But i have used it to push large amounts of data between plc and WinCC successfully!


Sharp7 is a C# port of Snap7 if BSEND is missing in Sharp7 its also possible to call the Snap7 library from C#

If you want to communicate to WinCC itself and not a S7 plc, then you need to use the WinCC programming api. This is split into two general parts: RT (runtime) and CS (configuration). With the runtime api you can read/write tags of the WinCC runtime, or connect to the message or taglogging runtime and get data. With the configuration api you can create / modifiy pictures, create variables and alarms and so on.

Both apis are in plain C in several dlls, so you need to program a wrapper to use them out of a .Net application. But the methods are not documented. The documentation you get when you buy the so called WinCC ODK (open development kit), which has documentation, programming examples, and from what I've read it may have a .Net wrapper in the latest versions. But it's not cheap.

The runtime api can be get open out of the WinCC professional documentation (which uses a WinCC 7.4/7.5 as runtime), but you need to compare and modify it to the minor differences in the WinCC 7.4 libraries.

Thomas_v2 said:

The documentation you get when you buy the so called WinCC ODK (open development kit), which has documentation, programming examples, and from what I've read it may have a .Net wrapper in the latest versions. But it's not cheap.

Click to expand...

I could have sworn this was a thing, but I was doubting myself when I couldnt find documentation on SIOS. Now I know why.

mk42 said:

I could have sworn this was a thing, but I was doubting myself when I couldnt find documentation on SIOS. Now I know why.

Click to expand...

You get the neccessary header files, which has also some documentation in it, and the variables are well described. For many functions further documentation is not needed if you have the time to try out, but some methods especially the ones which uses callbacks to transfer the requested data, are not obvious of how to use them. Many functions are used in Siemens sample applications inside of WinCC, the difference is when you want to use them outside of WinCC, you have to add a step to connect to the project itself first.

The ODK also delivers libraries to do static instead of dynamic linking, but I would always prefer dynamic linking in this case. The WinCC API is very stable, so developing an application should work with a lot of WinCC versions if linked dynamically.