Hello,

if we talk about DP network, in this case we ommit S7 communication and set true Profibus DP network. In this case you can only join your S7-300s CP 342-5 to needed DP network and configure on S7-400 I/O area for data Exchange between each S7-300 that are joined to this network. Look to also S7-300 CP properties about address and comm speed. All needed S7-300s must be connected at that DP network as you need, simply as S7-400 can Exchange data with them from that right DP port. Look to documentation and examples here on forum about DP connection via CP342-5, in each S7-300 Slave you need prepare instructions DP_SEND and DP_RECV with needed area. Again, look to S7-400 in area cfg what amount of data you can set as I/O buffer with each S7-300 DP Slave.

Hi,

Thank you for your reply. I tried to study little bit in documentation.

I set "DP master" for S7 400, then I tried "DP master" and also "No DP" = the result was the same, I could not set S7 connections.

As you can see from attached picture, S7 connection should be available fof both settings of S7 300 (DP master or No DP).

 What does "OC" means in the table ? I quess "S7" means S7 communication, DP means Profibus DP communication.

If I should use (7)/(2) selection (S7 300 CP as DP master/DP and S7 400 DP slave passive) I quess I should use DP_Send and DP_Recv function. Should I set anything in Netpro for this ? DP_Send and DP_Recv functions - where should be placed ? at S7 300 ? S7 400 ? Both of them ?

Thank you for your support.

Regards,

Georgio

Hello,

again pls, now we don't talk about S7 communication via DP network supported HW, we talk about real Profibus DP network. I see in this case my mentioned solution as S7-400 as Profibus DP Master and other S7-300s as Profibus DP Slaves, not S7 communication via PUT/GET, this is other type of protocol. In that mentioned screen (sry didn't look at that but I expect something) is more Solutions how to exchange data between S7 CPUs, again CPUs or other CPUs interfaces available. I see probably now some not correct understanding of terms. This isn't now in my opinion good way to explain this, you have still choice to use support request if you decide to.

Hi Duris_I,

Thank you again for your answer.

I hope that I understood well your comments. I looked deeply to the documentation and found attached table with communications blocks of user interfacces for DP communication.

If I understand well, I will use S7 400 as Master, S7 300s as slaves - I will set it in hardware configuration, I will set them on the same Profibus DP network. There will be no connection in NetPro.

In PLC program for S7 400: I will use SFC14 (DPRD_DAT) and SFC15(DPWR_DAT) from Standard Library / System functions blocks.

In PLC program for S7 300: I will use FC1 (DP_SEND) and FC2 (DP_RECV) from SIMATIC_NET_CP / CP300 library.

Thanks for support.

Regards,

Georgio

Georgio

Hi Duris_I,

Thank you again for your answer.

I hope that I understood well your comments. I looked deeply to the documentation and found attached table with communications blocks of user interfacces for DP communication.

If I understand well, I will use S7 400 as Master, S7 300s as slaves - I will set it in hardware configuration, I will set them on the same Profibus DP network. There will be no connection in NetPro.

In PLC program for S7 400: I will use SFC14 (DPRD_DAT) and SFC15(DPWR_DAT) from Standard Library / System functions blocks.

In PLC program for S7 300: I will use FC1 (DP_SEND) and FC2 (DP_RECV) from SIMATIC_NET_CP / CP300 library.

Thanks for support.

Regards,

Georgio

 Hello Georgio,

Have you already seen this:

DP link between CPU 315-2DP (slave) and S7-400 (master) with ...

DP link between CP 342-5 (slave) and S7-300/400 (master) with STEP ...

What should you watch out for when configuring a ... - Siemens Support

How to send more than 240 Bytes on CP 342-5? - Siemens Support

Hi Ste39,

Thank you for your links. I went through some links, but I am not sure if I wet directly through your posted ones.. I will go through it and I will let you know.

Thanks !

Regards,

Jiri

Hi all,

I made some investigation and finally I can use profibus CP with my new S7 400.

So I will have S7 400 CPU (6ES7414-3EM07-0AB0) with Profibus CP (6GK7 443-5DX01-0XE0).  This PLC will comunicate with 5x S7 300 (CPU 6ES7314-1AE03-0AB0, Profibus CP 6GK7 342-5DA00-0XE0).

I went back to try to use S7 communication, but I was not succesful. When I tried to use Marter-Slave system, there is a limitation in amount fo transfered data (If I remember well it is 88 bytes..).

 I need to communicate at least 400 bytes between PLCs. I established FDL connections between S7 400 and each S7 300. One FDL connection can use only 236B (236 data and 4 B header = 240B in total). I need more so I decided to add more connections for each node. There are 15 FDL connections in total (3 connections on each S7 400 and S7 300).

My question is: Will it work ? Does it sound OK ? Please see attached picture.

Thank you,

Regards,

Georgio 

Georgio

Hi all,

I made some investigation and finally I can use profibus CP with my new S7 400.

So I will have S7 400 CPU (6ES7414-3EM07-0AB0) with Profibus CP (6GK7 443-5DX01-0XE0).  This PLC will comunicate with 5x S7 300 (CPU 6ES7314-1AE03-0AB0, Profibus CP 6GK7 342-5DA00-0XE0).

I went back to try to use S7 communication, but I was not succesful. When I tried to use Marter-Slave system, there is a limitation in amount fo transfered data (If I remember well it is 88 bytes..).

 I need to communicate at least 400 bytes between PLCs. I established FDL connections between S7 400 and each S7 300. One FDL connection can use only 236B (236 data and 4 B header = 240B in total). I need more so I decided to add more connections for each node. There are 15 FDL connections in total (3 connections on each S7 400 and S7 300).

My question is: Will it work ? Does it sound OK ? Please see attached picture.

Thank you,

Regards,

Georgio 

 Dear Georgio,

I use FDL connection but under 240 bytes, does not know if a multiple call works on the same channel (never tried), however, try to see below also an S7 connection, may be fine for you?

FDL Protocol:

http://support.automation.siemens.com/WW/view/en/26098556

S7 Protocol:

http://support.automation.siemens.com/WW/view/en/26494206

Example:

http://support.automation.siemens.com/WW/view/en/18516182

Hi Ste39,

Thank you for your answer. Save and compilation was OK, so I hope that it will work normally, I hope !!

I want to use S7 connection ! But when I try to set it in NetPro, it is not possible  

Please see attached picture: "Local partner does not support S7 connections". This I do not understant at all. I thought that all Siemens devices are able to communicate via S7 connections ..

Thank you.

Regards,

Jiri

Hi,

Is there any information if I can use more FDL connections between two nodes in order to transfer larger amount of data ??

Unfortunatelly I cannot test it.

Thank you.

Regards,

Georgio