MB3480 MOXA MGate Modbus TCP to RTU/ASCII Gateway

The MB3480 MOXA (MGate MB3480) is an industrial high-density 4-port Modbus gateway engineered to connect large-scale Modbus RTU or ASCII serial networks directly to modern Modbus TCP Ethernet systems. Equipped with four software-selectable DB9 serial ports supporting RS-232, RS-422, and 2-wire/4-wire RS-485 interfaces, the MB3480 MOXA maximizes serial channel capacity in central electrical cabinets, bridging field instrumentation, multimeters, protection relays, and PLCs with supervisory SCADA backbones.

Designed to handle demanding industrial communications, the MB3480 MOXA supports up to 16 simultaneous Modbus TCP master connections while routing requests across four independent serial loops to manage up to 124 serial slave devices (31 per port). Outfitted with Moxa’s Automatic Data Direction Control (ADDC®) and intuitive web or software management utilities, it significantly reduces panel footprint, eliminates wiring complexity, and delivers reliable protocol conversion across complex control architectures.

Key Features of the MB3480 MOXA

• Quad Serial Channel Architecture: Features four independent software-configurable DB9 male ports for controlling separate RS-232, RS-422, or RS-485 serial multidrop loops.

• Bi-Directional Protocol Conversion: Converts bidirectionally between Modbus TCP over Ethernet and Modbus RTU/ASCII protocols over serial lines.

• High-Density Device Connectivity: Manages up to 124 Modbus RTU/ASCII serial slave devices across all four ports (up to 31 per port) while serving up to 16 concurrent TCP masters.

• Automatic Data Direction Control (ADDC®): Manages RS-485 driver enable timing automatically to ensure stable 2-wire and 4-wire multidrop bus operation.

• Industrial Power Input: Powered via a standard 3-pin terminal block accepting 12 to 48 VDC input for easy wiring in control panels.

• Comprehensive Management Options: Fully configurable using Moxa’s MGate Manager utility, Telnet, or standard web browser interfaces across standard Ethernet connections.

Primary Applications

• High-Density Power & Energy Monitoring: Consolidating multiple RS-485 loops of digital power meters, relays, and circuit monitors into central SCADA platforms

• Large Vessel & Offshore Telemetry: Interfacing multiple serial sub-networks—such as engine sensors, generator controllers, and manifold monitors—to Ethernet backbones

• Factory Automation & Building Systems: Integrating multiple serial PLC channels, VFDs, and environmental controllers into centralized control networks

Technical Specifications

Package Contents

• 1 × MB3480 MOXA MGate Gateway Unit

• 3-pin Terminal Block Power Connector

• Quick Installation Guide & Document Access Sheet