Thomas

I am new to communication between PLCs and have a project which includes a Schneider PLC using Unity as a master and WAGO Remote I/O as a slave which is through ethernet modbus. can anyone give me the idiots guide to ethernet modbus?

Regards,
Thomas

Just use the IO scanner function under the comms setup, and it should be almost idiot proof. Check the help in Unity, it is pretty good.

On the hardware side, setup your network as you would any other ethernet network, and best if it is segregated from any IT networks

I can get communication using the I/O scanning but i am not understanding how %MW and the modbus 10001 e.t.c relates to each other.

%MW are memory words and are equivalent to 4000x
%M are memory bits and are equivalent to 0000x
%I are inputs and are equivalant to 1000x
%Q are outputs and are equivalent to 0000x

As for communicating to a remote drop, I would guess it uses memory words (at least that is how Advantys works). Note the 1 offset.
%MW0 = 40001 and %MW0.0 = 40001.0
If bits can be read individually then %M0 = 00001