Hello.

I've a project with 2 simatic stations:

One with 313C + CP345-2 as a master of his own slaves

One with 315-2DP as a master of other slaves

All are in the same phisical profibus segment controlled by WinCC station.

I need to communicate both PLC to share data. In NetPro I can configure S7 link between CP345-2 and the 315 but when I try to configure con the 315-2DP side I've no option.

How can I communicate both PLC without purchasing extra components?

Thank you very much.

Hello JRubio;

You cannot use the integrated port of the CPU 315-2DP to process S7 communication blocks or connections. This is a feature of the CP 342-5 only, as it support S7 communications. The integrated port of a CPU (either MPI or Profibus) only supports S7 basic communications. The links below are a source of information on the subject..

If your MPI ports are available you can use them to connect the CPUs over S7 connections, using X_PUT/X_GET or X_SEND/X_RCV blocks. This FAQ can provide details:

Options for communication over MPI:

https://support.industry.siemens.com/cs/ww/en/view/21537047

There are many discussions on the forum on that subject, I can point this one out for you:

https://support.industry.siemens.com/tf/ww/en/posts/28684/

Follow the suggested link in that thread for information on data exchanges between CPUs.

Hope this helps,

Daniel Chartier

Thank you for your response.

However in NetPro I can configure S7 connection from CP342-5 to CPU315-2DP, only in this direction.

Why NetPro let me configure a useless link???

Hello,

if I good remember from my very old prj, in that time only S7-connection (via MPI) was allowed me with S7-400 xx CPU, via NetPro. Agree absolutelly with Daniel, but this something going inside my head now... Try create MPI network, connect that 2x CPU S7-300 via MPI and try create S7 user communication via NetPro. Give pls info. Now again to DP, as said Daniel, keep in mind that every DP modul/Port can be configured only Master or only Slave, in your situation with that 2 CPUs impossible to share data between them via DP.

Duris_I

Hello,

if I good remember from my very old prj, in that time only S7-connection (via MPI) was allowed me with S7-400 xx CPU, via NetPro. Agree absolutelly with Daniel, but this something going inside my head now... Try create MPI network, connect that 2x CPU S7-300 via MPI and try create S7 user communication via NetPro. Give pls info. Now again to DP, as said Daniel, keep in mind that every DP modul/Port can be configured only Master or only Slave, in your situation with that 2 CPUs impossible to share data between them via DP.

 You're possibly right.

I'll do two tests:

- Download the configuration as S7 comm... perhaps CPU 315-2DP can't be active partner(client) but it can agree to be a server. The GET/PUT blocks will be programed at the CP342-5 station doing nothing at the CPU315-2DP program.

- Create MPI net. This is obviosly the programmer easy way but it implies installing a new cable between stations which not are too far but not too close ;)

I'll inform you something.

Thank you.

Hello. SOLVED.

I was right at the first option.

Integrated Profibus port of S7-300 CPUs can handle S7 comm requests as a server being master or slave, don't care (in this project DP master).

I did the put/get requests from the CPU313C + CPU342-5 (DP master too) and the things go fine.

An unilateral link was generated from the CP module to the DP port of the 315-2DP and no modifications nor more code was needed to do to that statition.

Thank you very much.

JR

Hello,

eeeehm DP port on S7-300 315-DP2 f.ex. can be programed for DP communication, I have lot of my old projects with this implemented. Only what I made was define in DP Master/Slave respective I/O areas and everything working ok. Shame that I don't say this to you... But nothing important, you're working.

Thank you very much, I was looking a few days ago for a schema like this.