Dear experts!

I need to create a communication between 416-3 PN/DP CPU and CPU 315-2 DP with CP 343-1 Lean over Industrial Ethernet. I need to send more than 300 bytes both directions. Which S7 Communication function shall I use? AG_SEND, AG_LSEND or AG_SSEND? Is it possible to use BSEND and BRCV in this configuration?

Hi Pitons,

you have the following options:

- use Put, Get, then CPU 315 is Server; check this:

How do you program the function blocks FB14 "GET" and FB15 "PUT" in the S7 program of the S7-300 in order to transfer more than 160 bytes of data?

- use  AG_SEND/AG_REV or TSEND/TRCV

I would use AG_SEND/RCV at S7-300 and TSEND/TRCV over PN Interface of S7-400

Regards,

Towome

HI,

I am it again:

BSEND / BRCV is not possible if you make the connection over CP343-1 Lean.

This information you can also get in the following link/document:

CPU-CPU Communication with SIMATIC Controllers

 Check Page 96

Regards,

Towome

Thank you, Towome, for your reply!

Then I have next questions:

• what is faster - S7 connection or ISO on TCP?
• can I have S7 connection and ISO on TCP connection on the same 416-3 PN interface? (I have 8 more PLCs that are S7-300 series PN/DP type PLCs supporting S7 connection). If I can have ontly one type of connection and ISO on CP is slow, then Iļl have to change my CP so that I could communicate with all PLCs using S7 connection.
  
• how to configure ISO on TCP connection in TIA. I receive an error when I add new ISO on TCP connection (see screenshot). No interface can be selected for this connection.
  

Hi again,

what´s faster??? Please check this FAQ about

What properties, advantages and special features does the ISO-on-TCP protocol offer?

I have another FAQ for you called:

How you configure a connection in the TIA Portal?

I hope this helps a little bit.

Regards,

Towome

Thank you Towome for your efforts.

By FASTER I mean faster processing of block calls and received/sent data processing. For example for block AG_SEND in S7-300 help it is written "Transfer of data records up to 240 bytes results in better performance! This applies regardless of the block type used".

About TCON block. I'm currently trying to set up a connection, but I have several problems.

On CPU 416-3 PN/DP I'm not able to create a connection for ISO on TCP. TIA shows an error in Interface field, like there is no interface to connect this type of connection.

If I try to configure a connection under TCON FB, then in PLCSIM I don't receive any response on REQ signal - no DONE, BUSY or ERROR signal.