Hi everyone,

I am trying to configure modbus communication between my S7-416-3 (with CP443-1 attached on it) and several Schneider PLC.

I declared NetPRO connection as documentation said - one TCP connection with no remote @ and no remote port.

Then, I used MODBUS TCP wizard to create MODBUS_PARAM datablock using the right CP and the right connection.

Then I called MODBUSCP in OB1 and OB100 and gave parameters to FB108 block (one instance block for both).

Using modbus client simulator (ModbusPoll) I succedeed reading / writing values between both.

However, I do not completely understand how I can make it work with several clients.

My objective is to communicate with 4 Schneider PLC using different DB for each.

Should I create connections in NetPro and instanciate FB108 for each client plc ?

Thx in advance for your help guys ! :p

Hello,

Important thing, if you are using Modbus tcp wizard then it will create logical connection and save in one DB. You don't have to create again connection in net pro.

If you are not using Wizard then only u have to create connection in network . As per number of Sever , you need to create multiple connection in netpro or thru wizard.

As a fundamental, always multiple server can communicate with Single client not reverse  or Multiple slave with single Master not reverse.

Hello,

Thank you for your correction to me. But while working with S7300+CP , i used only wizard for modbus tcp . no netpro.

Hi MSX,

Kindly see attached files for MODBUSCP Server Client communication.