Hello All,

I am new to Beckhoff so apologies if my question is very simple. I am trying to create a simple Modbus Coil read using ModbusTCP.

I have done the following for the client:

• Called the FB (The attachment shows the configuration used) 
• Install TF6250 License
• Installed TCModbusSrv.exe
• Turned off Firewall

I have done the following for the server:

• Create the GVL, as per the manual
• Install TF6250 License
• Installed TCModbusSrv.exe
• Turned off Firewall

But I am getting an ErrorID of 32770, as per attachment.

I have stopped the TCModbusSrv process on the server and ran a modbus server simulation package (Modbus Slave) and the client then retrieves a good read and the correct coil state. This leads me to think I am doing something wrong on the server side, do you have any recommendations or suggestions where I am going wrong?

I have the same situation when trying to perform the read virtually across two VMs and when using two Beckhoff PLCs

Thank you for any help