Hello Everyone !

I have to communicate 3 S7300 CPU's with single touch panel TP1200k. Profibus port is available on both sides (3 CPU's and HMI). I know that i can define multiple nodes in Wincc flexible for communication. but due to lack of knowledge i am bit confused about communication.

Hello jolter;

The nature of your question is not clear tp me.

Based on the drawing you have attached, I would think that you are trying to decide if you need a line structure or a star topology for your Profibus network. If that is the case, you must take into account the fact that Porofibus is designed normally for line topologies, in daisy-chain construction with Profibus cable and Profibus connectors, as you depict in the top part of your schematic.

If you wish to implement a star structure, you need to add a star hub module between the TP1200 and the CPUs, something like Procentec's ProfiHub:

https://procentec.com/products/profihub/units/profihub-b5plusr/

Next: the configuration of the network will be done in the HMI software, which will act as a Master Class 2 on Profibus, so it can interrogate every CPU it needs to collect data from. 

Hope this helps,

Daniel Chartier

Hello Everyone !

I have to communicate 3 S7300 CPU's with single touch panel TP1200k. Profibus port is available on both sides (3 CPU's and HMI). I know that i can define multiple nodes in Wincc flexible for communication. but due to lack of knowledge i am bit confused about communication development.

1- I have attached snap here for your reference. Two topologies are mentioned in attachment. Could any one tell me which one is correct for my task.

2- if i connect 3 CPU's in bus topology and connect HMI at one end,  Is there any need to define all connected CPU's in each PLC program  (step 7) hardware configuration as we do for ET stations.

3-  if I connect all CPU's with HMI in star topology, where profibus switch (on /off) will be kept for terminating resistor at each plc end?

Thanks

hi jolter ggg,

Profibus only allows line-topology

For other topologies you need other active components like repeater

have a look to the Profibus Network manual

hope this helps,

regards,

thanks for your reply.

please review attachment. could we make star topology by using these connectors at HMI port.

could we implement below mention scenario.

#  I will connect double sided Bus connector at HMI port and then i will connect single sided connector on top of double sided connector.

Two PLC connection is terminated in double sided connector and one PLC connection is terminated in single side connector.

total 3 PLC we have for this task. all PLC connection are gathering at HMI port directly. 

Hello jolter ggg

I would not to use this kind of wiring. If you use these "double Plug" then you create a kind of branch line. This could dramatically decrease your Profibus quality.

you could try to use a different Bus Segment with a Profibus Repeater.

but why do you want to use a star topology with Profibus that is made for Line topology??

Bye Murof

you say "thanks for reply", but have you read my reply?

Profibus  ----> only line topology

with repeater ---->  open a branch/new line

regards,