Hi all!

I have to establish communication in a network with 9 nodes of S7-1200 and PC running WinCC Advanced.

Each node has S7-1200 with local KP400 HMI. This local data exchange is 70bytes or 40 tags for each node.

Each node has to communicate (have HMI connection) with WinCC exchanging 100 to 300 bytes (70 to 200 tags) each.

Between PLCs in nodes, i got also communication:
Node A gets 10bytes and puts 10bytes to node C.
Node B gets 10bytes and puts 10bytes to node C.
Node C gets 10bytes and puts 10bytes to node D.
Node D gets 10bytes and puts 10bytes to node E.
Node E is Profinet IO controler to a ProfinetIO devices node F and node G (35 bytes exchange each).
Node F gets 10bytes and puts 10bytes to node H.
Node H is Profinet IO controler to a ProfinetIO device node I (35 bytes exchange).

(Please see drawing attached)

TIA portal V13 allows me to create such network and all connections.
Manuals says that for most distant node I (from WinCC) frame delay for 7 switches is total 0,35sec max.

But,

Is it possible to realise?
What about frame collison?
Would I have communication timeout for WinCC HMI connections, PUT/GET, loacl HMI connections, Profinet communication?

Thanks!

Hello Homoroid;

Looks like a nice little project. And congratulations on your documentation.

I think your fears are exagerated. If this is all the traffic that will transit on your network, you should be usingvery little bandwith, and your collision rates should be low.

Of course the timimg you show on your table are the switches transition times for the signals. You cannot expect the point-to-point delays to be as short, because you have to take the functions (send and recieve) timings into account to generate and recieve the messages. But you should find that if TIA Portal allows you to build and download all the connections then they should work.

Hope this helps,

Daniel Chartier

You can configure in TIA (also in older Step7) the length of cables and extra delays (switches, routers).

As for collision, it is handled automaticaly on ethernet physical layer - it would be impossible for any company LAN to work if this is a real problem.

As for your application, I have seen older S7-300 with profibus (automated warehouse) with quite the same complexity and it is working without problems. Indeed your project is complex and you will probably face to some difficulty, but in my opinion it is far from mission impossible.