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Adroit SCADA connection to Melsec FX3U PLC via serial communication using the Mitsubishi FX Serial MITFXS protocol driver

Adroit SCADA connection to Melsec FX3U PLC via serial communication using the Mitsubishi FX Serial MITFXS protocol driver

This article’s purpose is just to provide some basic and fundamental tips and resources on how to configure a Melsec FX PLC to connect to Adroit SCADA via Modbus serial (RTU) communication protocol.

First off, the serial communication standard applicable for this article is RS-232 based (not RS-422 based - however, some information is common to both). The Built-in serial communication port on the FX PLC is an RS-422\RS-485 serial communication port.
Thus, for this purpose, an external RS-232 communication adaptor will be required to be added to the PLC CPU.

The settings in Adroit Setup – psexe.exe

The additional card added to the PLC, based on the fact that you want to communicate via Modbus serial communication protocol is the FX3U-232ADP-MB communication special adapter.
This is the only card applicable:

Channel: ch2 to be used

However, besides the above – programs have to be written to accommodate the communication.

(it must be pointed out that no communication in the automation world is plug-configure-play. Commissioning will always be required, and troubleshooting and fault-finding will always be part of the commissioning process)

That said:
Some procedures in creating programs:

Some sample program examples:

If your PC does not have an RS-232 port, and you are using a serial to ethernet converter to change the communication medium to ethernet, then it is important to understand that the communication protocol is still Modbus RTU (Serial). Only the transmission medium has changed to Ethernet.

As such, the serial to communication converter must have software that maps the information transferred via the ethernet port to a serial communication port (this is a 3rd party software and setup, independent of Adroit and Mitsubishi).

Additional Resources:
The following additional resources can be used as supplementary information for reference purposes:
In addition – please find the FX3U-232ADP-MB communication special adapter information:
Installation Manual

MODBUS Serial Communication Edition

Data Communication Edition

Basic & Applied Instruction Edition

Hardware Edition

Otherwise – there are other manuals available:

In addition - the Adroit Modbusi.pdf driver document is to be utilized for configuration purposes as well.
C:\Program Files (x86)\Adroit Technologies\Adroit\Drivers\modbusi.pdf