Converting MODBUS RTU to MODBUS TCP: A Guide for Industrial Automation Professionals

=====================================================================================

In today's increasingly connected industrial automation landscape, the need for seamless communication between legacy systems and newer Ethernet-based devices has never been more pressing. One common challenge faced by engineers working with older serial-based instruments is integrating them into modern Modbus/TCP networks while maintaining the robustness of their existing MODBUS RTU infrastructure.

This article will provide a step-by-step guide on how to successfully convert your MODBUS RT-485/422 (RS-485 or RS-422) protocol communications over a single fiber-optic cable using Moxa's MB3180 Modbus/Modbus Plus-to-Ethernet device. By following this tutorial, you'll learn how to effortlessly transition from the tried-and-tested reliability of serial MODBUS RTU to the greater flexibility and scalability offered by Ethernet-based MODBUS TCP/IP networks.

Hardware Requirements

----------------

* Mox- MB3180 Modbus/Modbus Plus-to-Ethernet device (or equivalent)

* Red Lion DA10, DA30, DA50 & DA70 Group 2 or above devices

Software Requirements

------------------

None. This conversion process is entirely hardware-based and does not require any additional software drivers beyond what comes pre-installed with your Moxa MB3180 device.

Step-by-Step Conversion Process:

### Step 1: Physically Connect the Devices

* Plug one end of a Cat5e or higher Ethernet cable into Port A (TX) on the DA50 Group 3 Red Lion device.

* Similarly, connect another end of the same cable to Port B (RX+) and C (RTS/CTS) on Moxa's MB3180 Modbus-to-Ethernet device.

### Step 2: Configure MODBUS RTU Master Settings

1. Connect a serial terminal such as Hyperterminal or similar application to COM4 (RS-232) port of the Red Lion DA50.

2. Set baud rate to 9600bps, Data bits = 8bits and Parity = Even.

3. Open Serial Port Configuration window from 'Port' menu in hyperterm.

### Step 3: Configure MODBUS RTU Slave Settings

1. Connect another serial terminal such as Hyperterminal or similar application to COM4 (RS-232) port of the Red Lion DA50.

2. Set baud rate to 9600bps, Data bits = 8bits and Parity = Even.

### Step 4: Configure MODBUS TCP/IP Client Settings

1. Open Device Configuration window from 'Tools' menu in Modbus Master software or similar application used for configuring MODBUS devices via Ethernet.

2. Select 'Modbus/TCP' as the protocol, enter IP address of Moxa MB3180 device (default is 192.168.10.1) and port number as 502.

### Step 5: Test Communication

* Use Modbus Master software or similar application to send MODBUS RTU commands from a serial terminal connected directly to the Red Lion DA50.

* Verify that these same commands are received correctly at Moxa's MB3180 device via its Etheret port using another instance of ModbusMaster or equivalent tool.

-------

By following this step-by-step guide, you've successfully converted your MODBUS RTU serial communications over a single fiber-optic cable to the greater flexibility and scalability offered by Ethernet-based MODBUS TCP/IP networks. With Moxa's MB3180 device handling all necessary protocol conversion duties in the background without requiring any additional software drivers or configuration beyond what comes pre-installed with each component, integrating legacy instruments into modern industrial automation systems has never been easier.

By leveraging this powerful hardware solution and following best practices outlined above when migrating from MODBUS RTU to MODBUS TCP/IP networks, you'll be able to unlock significant benefits such as improved system reliability through redundant communication paths, enhanced scalability for future-proofing your existing infrastructure against growing data demands.

Conversor modbus rtu a modbus tcp