AiGW300 3-Port Modbus Multi-Master Gateway: LoRa Wireless + Ethernet Data Sharing Solution

AiGW300 Product Overview

The AiGW300 is a self-learning Modbus multi-master communication gateway developed by Shenzhen Yitian Guanglian Technology Co., Ltd. It is a full-duplex 3-channel RS485/RS232 multi-master communication device. The gateway supports Ethernet, fully automatic operation without Modbus parameter configuration, supports bidirectional conversion between Ethernet, serial, and TDD/7020. It has been verified by numerous practical engineering projects, is stable and reliable, supports transparent transmission mode, and comes with lifetime maintenance.

The AiGW300 integrates 3 RS485 serial ports, 2 RS232 serial ports, 1 Ethernet port, and a LoRa wireless communication interface. It enables slave device data to be simultaneously shared with RS485 hosts, Ethernet hosts, and LoRa wireless hosts, making it an ideal solution for multi-system sharing of serial device data in industrial environments.

Key Product Features

• Full-duplex 3-channel RS485/RS232 multi-master communication: Supports multiple serial ports working simultaneously for parallel multi-master communication
• Ethernet support, fully automatic operation, no Modbus configuration required: Self-learning mode automatically identifies Modbus protocol, ready to use out of the box
• Supports bidirectional conversion between Ethernet, serial, and TDD/7020: Flexible conversion between multiple interfaces to meet different scenario requirements
• Verified by numerous practical engineering projects, stable and reliable: Has been operating stably in many industrial sites for a long time
• Supports transparent transmission, lifetime maintenance: Transparent mode is protocol-independent, with lifetime technical maintenance

Hardware Interface and Indicator Description

Interface Layout

The AiGW300 gateway features industrial-grade DIN rail mounting. Interfaces from left to right are: Ethernet port (LAN), RS485 1, RS485 2, RS485 3, RS232 1, RS232 2, and power terminals (Power Supply). A LoRa antenna interface is located on the top for connecting a LoRa antenna to achieve wireless communication.

Serial Port Definitions

• RS485 1: Terminal definitions A+, G, B-, for connecting Modbus host or slave
• RS485 2: Terminal definitions A+, G, B-, for connecting Modbus host or slave
• RS485 3: Terminal definitions A+, G, B-, for connecting slave devices to be shared or RS485 bus
• RS232 1: Terminal definitions Rx, G, Tx, for connecting RS232 serial devices
• RS232 2: Terminal definitions Rx, G, Tx, for connecting RS232 serial devices

Power Interface

Power supply range is DC 8-36V wide voltage. Power terminal definitions:

• PWR-: Power negative, connect to power adapter black wire
• PWR+: Power positive, connect to power adapter red wire
• Ground terminal: Connect to protective ground

Indicator Definitions

• Power (red): Power indicator, solid on when powered
• Active (green): Running status indicator, flashes during normal operation
• Socket/Lora (red): Network/LoRa communication indicator, flashes during data communication
• 1 (black): RS485 1 serial communication indicator
• 2 (black): RS485 2 serial communication indicator
• 3 (black): RS485 3 serial communication indicator

Four Operating Modes Detailed

The AiGW300 supports four operating modes, users can flexibly select according to field requirements:

Mode 1: Self-Learning Modbus Multi-Master Mode

This is the core function mode of AiGW300, using patented self-learning autonomous polling buffer technology to achieve simultaneous sharing of slave data by multiple hosts.

Connection method:

• LoRa wireless: Waits for host to read/write data, uses Modbus RTU protocol for对接
• RS485 1 to 2: Connect to host, uses Modbus RTU protocol
• Ethernet port: Connect to host, supports Modbus TCP port 502 (32 concurrent connections) and Modbus RTU port 7020 (8 concurrent connections)
• RS485 3: Connect to slave devices to be shared or RS485 bus, such as flow meters, energy meters, PLCs, etc.

Working principle: The self-learning autonomous polling buffer automatically learns the host's Modbus query commands, caches the slave response data, and distributes it to each host. Slave data (such as flow meters, energy meters, PLCs, etc.) can be simultaneously shared with RS485, Ethernet, and LoRa wireless, achieving real-time performance no less than direct connection. Requires slave devices to use Modbus RTU communication protocol.

Mode 2: Serial and LoRa Wireless Transparent Transmission to Ethernet Mode

In transparent mode, all serial and LoRa wireless data is transparently transmitted to Ethernet, regardless of communication protocol.

TCP/IP port mapping:

• TCP/IP port 6023: Corresponds to LoRa wireless
• TCP/IP port 6020: Corresponds to RS485 1
• TCP/IP port 6021: Corresponds to RS485 2
• TCP/IP port 6022: Corresponds to RS485 3

Connection method: RS485 1 to 3 connect to slave devices, such as flow meters, energy meters, PLCs, etc. In transparent mode, any communication protocol can be transparently transmitted to Ethernet.

Mode 3: LoRa Wireless Transparent Transmission to Serial Mode

Remote hosts can directly read/write slave devices connected to RS485 port 1 via LoRa wireless. Communication is bidirectional transparent mode, regardless of communication protocol.

Port mapping:

• LoRa wireless: Transparent to RS485 port 1, remote host can directly read/write slave devices
• TCP/IP port 6021: Corresponds to RS485 2
• TCP/IP port 6022: Corresponds to RS485 3

RS485 1 to 3 connect to slave devices, such as flow meters, energy meters, PLCs, etc. In transparent mode, any communication protocol can be transparently transmitted to LoRa wireless and Ethernet. Note: This mode does not support multi-master communication.

Mode 4: Serial and LoRa Wireless Shared Server Mode

Use the local Ethernet port to read/write slave device data connected to a remote AiGW300 gateway or third-party LoRa module via LoRa wireless, and supports multi-master communication.

TCP/IP port mapping:

• TCP/IP port 6023: Read/write LoRa wireless
• TCP/IP port 6020: Read/write RS485 1
• TCP/IP port 6021: Read/write RS485 2
• TCP/IP port 6022: Read/write RS485 3

Multi-master support: RS485 1 to 3 and LoRa wireless all support 8 TCP/IP hosts simultaneously reading/writing data. The对接 protocols are Modbus TCP and Modbus RTU. This mode establishes an independent self-learning autonomous polling buffer for each host port and LoRa wireless to achieve multi-master communication. RS485 1 to 3 connect to slave devices, such as flow meters, energy meters, PLCs, etc., requiring slave devices to use Modbus RTU communication protocol.

Technical Specifications

Wiring Instructions

1. Ethernet port (LAN): Connect to switch or host network port with Ethernet cable
2. RS485 1 and RS485 2: In multi-master mode, connect to Modbus hosts (such as touch screens, PLCs, configuration software, etc.), A+ to host A terminal, B- to host B terminal, G to common ground
3. RS485 3: Connect to slave devices to be shared (such as flow meters, energy meters, PLCs, etc.), A+ to slave A terminal, B- to slave B terminal, G to common ground
4. RS232 1 and RS232 2: Connect to RS232 serial devices, Rx to device Tx, Tx to device Rx, G to common ground
5. LoRa antenna: Screw the LoRa antenna tightly onto the antenna interface, ensure good contact
6. Power: PWR+ to DC power positive (red wire), PWR- to DC power negative (black wire), ground terminal to protective ground

Typical Application Scenarios

• Smart Water: Flow meter data simultaneously shared with local SCADA, water management platform, and remote monitoring center
• Energy Management: Multi-system acquisition of energy meter data, simultaneously uploaded to energy management system and financial system
• Industrial Automation: PLC data simultaneously uploaded to local touch screen and cloud IoT platform
• Smart Building: Multi-system sharing of building control device data without duplicate wiring
• LoRa Wireless Remote Monitoring: Remote reading/writing of field device data via LoRa wireless, suitable for hard-to-wire scenarios
• Non-standard Protocol Device Networking: In transparent mode, any serial protocol can be transmitted via Ethernet or LoRa wireless