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MELSEC RJ71EN71 — PLC-side settings

MELSEC RJ71EN71 — Ethernet communication unit for iQ-R series.

What you need

  • Configuration tool: GX Works3
  • Network: Align IP address, subnet mask, and default gateway with your network environment.
  • After configuration: Power cycle the PLC to apply the new parameters.

Example values used in this guide

Parameter Example value Notes
IP address 192.168.250.100 Adapt to your network
TCP port 1025 SLMP TCP
UDP port 1035 SLMP UDP

PLC-side settings

Use the RJ71EN71 when the iQ-R CPU module does not have a built-in Ethernet port. The library profile is separate so configuration can name the communication unit explicitly. It uses 4E frames with iQ-R compatibility.

Screen: Unit parameters

Parameter Setting
IP Address 192.168.250.100 (example)
Subnet Mask Match your network
Default Gateway Match your network
Write Permission During RUN Permit all (SLMP)
Communication Data Code Binary
Open Method Setting Do not open via program

Screen: Remote device connection settings

Parameter TCP UDP
Communication Method SLMP SLMP
Protocol TCP UDP
Port Number 1025 1035
Keep-Alive Enabled UDP

Connecting with this library

Parameter Value
Canonical profile melsec:iq-r:rj71en71
Frame and compatibility 4E, iQ-R
Port (TCP) 1025
Port (UDP) 1035

Code example:

import asyncio

from slmp import SlmpConnectionOptions, SlmpTarget, open_and_connect, read_typed


async def main() -> None:
    options = SlmpConnectionOptions(
        host="192.168.250.100",
        port=1025,
        transport="tcp",
        plc_profile="melsec:iq-r:rj71en71",
        default_target=SlmpTarget(network=0, station=0xFF, module_io=0x03FF, multidrop=0),
    )
    async with await open_and_connect(options) as client:
        value = await read_typed(client, "D100", "U")
        print(f"D100={value}")


asyncio.run(main())

using PlcComm.Slmp;

var options = new SlmpConnectionOptions(
    "192.168.250.100", SlmpPlcProfile.IqRRj71En71, 1025,
    SlmpTransportMode.Tcp, SlmpTargetAddress.OwnStation);
await using var client = await SlmpClientFactory.OpenAndConnectAsync(options);
var value = await client.ReadTypedAsync("D100", "U");
Console.WriteLine($"D100={value}");

The PLC-side settings on this page apply to every language. For Rust, C++ (Arduino/PlatformIO), and Node-RED, start from each library's Getting started.

Screenshots

RJ71EN71 unit parameters screen RJ71EN71 unit parameters screen.

RJ71EN71 remote device connection settings screen RJ71EN71 remote device connection settings screen.