In connection with the transferring of data between the FX5 and Adroit SCADA using Modbus TCP communication protocol – this write-up will provide the required information to facilitate this requirement.

However, please note this is not recommended. The SLMP communication is recommended for Melsec PLCs.

Furthermore, even if you use the FX5 communication port for MB TCP communication with other devices – you can still use SLMP communication to the Adroit SCADA. Hence, there is no reason to be constrained in using MB TCP communication.

FX5 PLCs are not designed to be MB TCP masters. They are intended to the MB TCP slaves. When connecting a PLC to a SCADA via Modbus TCP, then the PLC is expected to be a master. However, Adroit SCADA is the Modbus TCP master, and there can only be one master in a communication network.

That said – it is still possible to use the Modbus Ethernet device driver in Adroit SCADA to transfer data between a FX5 and Adroit SCADA. (the procedure given here, applies)

The Implementation Strategy

First – the Implementation strategy is the be identified and one such would be as follows:

  • Step one: Setup the PLC communication details and connect the PLC on a network
  • Step two: Connect the Adroit SCADA server on the switch (the PC and PLC must be on the same network range)
  • Step three: Create a driver instance (A device) – with the correct settings
  • Step four: Start Adroit Agent server (licensed), Smart server, User Interface.
  • Step five: Create tag and scan it to the device.
  • Step six: Open the setup again – and confirm that the device is green.

The Register Addressing for Tag Scanning:

For this implementation, it is important to note that when it comes to the scanning of Modbus address registers from a FED device, there is a matter of Modbus Addressing vs IEC Addressing.

Just also note that Modbus addressing and Melsec PLC addressing for registers are different. Therefore, the following formula applies, when transferring word registers (16bits)

Melsec to Modbus Addressing

In other words, if you require to scan D30 in FX5, the tag in Adroit will be scanned as 40031.

With all this in mind – please note the following procedure.

The Implementation Method:

The following Method holds:

Adroit to FX5 address scanning

Resources: Video Procedures

The Following video procedure videos for the above-mentioned implementation method applies for this procedure write-up:

Part1 – PLC comms & small generic number generator

Part2 – Setting up the Adroit MBTCP Device driver

Part3 – Scanning a Device register in MB (non-IEC) format and test data transition

Part4 – Scanning Integers, Double-Integers and Real value

The above video procedure and sample programs for both SCADA and FX5 PLC given for the transfer of Integer, double-integer and real values.

Reference and Information Resources

​The GX Works3 PLC program applicable:

The Adroit SCADA program applicable: