I have setup comms from a PLC where I have modbus RTU out on RS485 and TCP/IP simultaneously! The RS485 goes to a serial to ethernet conversion (Lantronix XPress is used). Is there any difference between the Modbus that comes direct from the PLC and the Modbus from the conversion?

 

NOT Different, but you shall program/set the Lantronix for interfacing, sometimes you shall download the latest software frame from internet to run the Lantronix properly.

It was used for flow computer network.

Regards,

Yuliwanto