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Melsec Q series Modbus Ethernet TCP communication - Built-in Ethernet Port

Melsec Q series vs Melsec iQ-R series Modbus Ethernet TCP communication - Built-in Ethernet Port - Modbus TCP Communication options.

R-series:
RJ71EN71 Does support the Modbus TCP Communication protocol
For Master:


Only: RnENCPU or RJ71EN71

For Slave:


Only: RnCPU (CPU Module), RnENCPU or RJ71EN71

Q-series: (or L-series)
QJ71EN71 Does NOT support Modbus TCP Communication protocol
QnUDE or QnUDV Does NOT support Modbus TCP Communication protocol
For Q-series to do Modbus TCP Use QJ71MT91. (Recommended … we support this)

Note:
However, there is also the option of the function block below.
It does work (tested), but this is not an official Mits FA elec solution, and therefore no technical support is available on this. (the official solution is to use QJ71MT91.)

The Information of this function block is as follows:

Modbus TCP Communication via QnUDE and QnUDV CPUs:
Product : Q-Series
Title : Modbus TCP Communication

Software Configuration

  • Software : GX Works
  • Library : QnUDEHModbusTCP_GW2_V100
  • FB : QnUDEHModbusTCPClient

Note : Do not compile the connections used with the FB.

Once the connection is established, you can perform read-and-write procedures (see the manual for a complete description).

Writing

  • FirstAddress : TRUE
  • Read : FALSE
  • Write : TRUE
  • WriteStartAddr : 16#0
  • WriteNoOfDevs : 16#8 (128 bits)
  • BitOrRegister : FALSE (registers)

To execute the command:

Reading

  • FirstAddress : TRUE
  • Read : TRUE
  • Write : FALSE
  • ReadStartAddr : 16#200
  • ReadNoOfDevs : 16#8 (128 bits)
  • BitOrRegister : FALSE (registers)

To execute the command:

Resources:
The function-block library:
https://drive.google.com/drive/folders/12kxqcZI21VsyovIlpr7elb7ZrihFJiAF?usp=sharing