ModbusTCP/IP multi-servers problem

Hello Everyone,

I am able to use S7-315F-2PN/DP as client to communicate with one Wago 750-841 Ethernet controller .But now I need to communicate two.
I was wondering that how many FB102 should be use for this. Can I use one fb102 to do this and just modify DB parameters which is created by Modbus TCP/IP Wizard. if can do this with one FB102, Which parameters
should be modified.

By the way I can get correct data from 841 and put data to 841 successfully,Only one 841. But SF led of S7-300 is slow flash. I get some information for Diagnostic buffer. EventID: 16#A090 Area lenght error when reading. I get the Fb102 as Example from Siemens website.
It is a demo version. I copy corresponding Functionblock into my project. I want to know what different between Demo version and formal version is. whether Demo version causes the SF alarm.

Above communication is only test to communicate between S7300 and 841 via ModbusTCP/Ip.

I will purchase Formal version later for my project.

Thanks in advance.

Best Wishes

Dear Wuestenraeuber,

Thank you for your prompt reply. It hepls a lot. I will follow your instructions to do it. As you said
there is two methods for it. I'd like to know which one is better ifS7300 has enough memory to do

it. By the way I used two FBs with two different instances DB to do the communication and it was

working well. If I want to use one FB with modification parameters of DB which is created by

Modbus wizard. You said that I need to disconnect first connection. How to disconnect established

connection. I set oneto "CONTROL_DAT".DISCONNECT whether the established connection can

be disconnected by this bit.

How long I can use demo version to communicate with partners normally? In my memory, It will

be unavailable after two hours when plc is switched from stopto run. Is that right.

Thanks.

Best Wishes

New question published by lesther roque is split to a separate thread with the subject Can't find CONTROL_DAT.DISCONNECT.

Best regards
Jen_Moderator