Your comments

note: I am using an LM Gateway201 as an OPC server

It did`n work

I tried read a node

NONE is checked in certificate

Use FX3U as modbus master. I use commands IVWR and IWRD. I use a RS485/ethernet converter

Did you make modbus work as client?

I noticed that to work as a client it is necessary to enter with ip, port and id (station number, which is a modbus address).
The field for id is missing

Will you implement this?

We use modbus in WEG PLC300 ,  mitsubishi FX3u, schneider and much more.