Moxa MGate MB3170-M-SC-T 1-Port Modbus Gateway with Multi-Mode SC Fiber (Wide Temp)

Overview

The Moxa MGate MB3170 and MB3270 are 1 and 2-port advanced serial-to-Ethernet Modbus gateways that convert between Modbus TCP, RTU, and ASCII. Beyond standard TCP-to-serial gateway operation, they uniquely support serial-master-to-serial-slave communication and allow simultaneous serial and Ethernet master access to the same RTU/ASCII slave devices — making them ideal for retrofitting Modbus TCP onto existing serial Modbus networks without disrupting the original architecture.

Key Features

• Converts between Modbus TCP, Modbus RTU, and Modbus ASCII protocols
• Auto Device Routing: single-click slave ID table setup for SCADA integration
• Route by TCP port, IP address, or ID mapping for flexible deployment
• Accessed by up to 32 Modbus TCP clients (32 simultaneous Modbus requests per master)
• Connects to up to 32 Modbus TCP servers; up to 31 (MB3170) or 62 (MB3270) RTU/ASCII slaves
• Serial redirector: serial and TCP masters can access serial slaves simultaneously (MB3270)
• Emergency request tunnels with priority control for QoS on urgent commands
• Built-in Ethernet cascading (2 x 10/100BaseT(X) RJ45) for daisy-chained wiring
• 100BaseFX fiber options (multi-mode SC/ST or single-mode SC) — up to 4 km MM, 40 km SM
• RS-232/422/485 software-selectable per port
• 2 kV serial isolation on -I models
• Embedded Modbus traffic monitoring for installation-stage troubleshooting
• Redundant dual DC power inputs (12–48 VDC) and 1 relay output
• HTTPS (TLS 1.2), SNMPv3, AES-256 security
• ATEX, IECEx, Class I Division 2 hazardous location and DNV maritime certification
• Wide-temperature (-T) models: -40 to 75°C
• 5-year warranty

Modbus Network Integration

Each serial port can be independently configured for Modbus RTU or Modbus ASCII operation, with software-selectable RS-232/422/485 standards. The MB3170 provides 1 serial port (DB9 male for RS-232, terminal block for RS-422/485). The MB3270 provides 2 x DB9 male serial ports. Supported Modbus functions: 1, 2, 3, 4, 5, 6, 15, 16, 23. ADDC simplifies RS-485 wiring; pull high/low resistors (1 kΩ / 150 kΩ) and 120 Ω termination are user-selectable.

Fiber Variants

For environments with high ground-loop voltages, electromagnetic interference, or hazardous-area sparking concerns, MB3170 fiber models replace the RJ45 Ethernet ports with 100BaseFX optical fiber — multi-mode SC or ST connectors for distances up to 4 km, or single-mode SC for distances up to 40 km. Fiber provides complete galvanic isolation and is well suited to power utility, oil and gas, and heavy industrial environments.

Security & Management

Configuration is via Web Console (HTTP/HTTPS), MGate Manager utility, MCC Tool, or Telnet. Network management includes SNMPv1/v2c/v3, SMTP email alerts, NTP client, and LLDP. Security features include HTTPS (TLS 1.2), AES-128/256 encryption, SHA-256, and local database authentication.

Power & Environmental

All models accept 12 to 48 VDC via redundant dual power inputs on a 7-pin terminal block. A relay output provides alarm signalling for power and Ethernet faults. Standard models operate 0 to 60°C; -T models extend to -40 to 75°C. Plastic housing with IP30 rating.

Certifications

CE (EN 55032/35), FCC Part 15B Class A, UL 60950-1, EN 62368-1, UL 508. ATEX, IECEx, Class I Division 2 hazardous location. DNV maritime certified. EMS to IEC 61000-4-2/3/4/5/6/8/11. MTBF up to 1,662,526 hours (Telcordia SR332).