General
Data bits	7, 8
Stop bits	1, 2

The Moxa MGate MB3170-T is an industrial network gateway for bidirectional conversion between Modbus RTU/ASCII and Modbus TCP. It serves as a bridge between serial devices and Ethernet-based systems, enabling the integration of existing legacy systems into modern, IP-based networks. The device is specifically designed for applications with high communication volumes and complex network topologies, such as those found in industrial automation, power supply, or process control.

Applications
This gateway is suitable for industrial environments where serial devices such as sensors, actuators, or control units communicate via Modbus RTU/ASCII but need to be accessed over an Ethernet network. It is frequently used in SCADA systems to transmit data from field devices to central control and monitoring systems. Support for up to 62 serial slaves and up to 32 Modbus TCP clients enables connection of numerous devices via a single unit. The function for simultaneous use of serial and Ethernet master access allows for flexible network architecture without requiring modifications to existing systems.

Functions and Equipment in Detail
The MGate MB3170-T features a serial port (DB9, RS-232/422/485) and two Ethernet ports (10/100BaseT(X), RJ45). The serial interface supports baud rates from 50 bps to 921.6 kbps, data bits 7 or 8, parities such as None, Even, Odd, Space, and Mark, as well as stop bits 1 or 2. Flow control is achieved via DTR/DSR, RTS/CTS, or RTS Toggle (RS-232). For RS-485, integrated ADDC protection circuits, pull-high/low resistors (1 kΩ/150 kΩ), and a 120 Ω terminator are provided. The device supports the Transparent Mode, which enables direct forwarding of serial data over Ethernet without protocol conversion.

Technology Explained Simply
The conversion is bidirectional: a Modbus RTU/ASCII device can be accessed over Modbus TCP via the gateway, and vice versa. The Auto Device Routing function automatically detects connected serial devices and configures routing rules, simplifying setup. The Emergency Request Tunnels allow prioritization of critical commands, ensuring important control commands are not delayed even under high network load. Communication is managed via IP-based routing rules, which can be controlled by IP address, port, or device ID. Device management is performed via a web console (HTTP/HTTPS), Telnet, the MGate Manager, DSU, or MCC Tool. Additionally, the gateway supports SNMPv1/v2c/v3, HTTPS (TLS 1.2), and encryption with AES-128/256 and SHA-256 for secure communication.

Compatibility and Accessories
The gateway is designed for use in industrial networks and supports Modbus TCP Client/Server as well as Modbus RTU/ASCII Master/Slave protocols. Optional fiber optic connections (100BaseFX) are available, enabling interference-free data transmission over distances up to 4 km (multimode) or 40 km (singlemode). The -I models offer galvanic isolation of 2 kV, enhancing electromagnetic immunity. The devices are suitable for use in hazardous environments and comply with certifications such as ATEX, IECEx, DNV, UL 60950-1, UL 508, EN 62368-1, as well as EMC standards EN 55032/35 and FCC Part 15B Class A.

Mounting and Installation
The device is designed for DIN rail mounting and features a plastic housing with protection rating IP30. Dimensions are 29 x 89.2 x 124.5 mm (with flanges). Power supply is via a 7-pin terminal block in the range of 12–48 VDC. Power consumption is 435 mA at 12 VDC for standard models, and 510–555 mA at 12 VDC for -I models. An integrated relay output (1 A @ 30 VDC, resistive load) enables control of external loads. Operating temperature ranges from 0 to 60 °C for standard models, and from -40 to 75 °C for wide-range models. Storage temperature is -40 to 85 °C, and humidity is between 5 and 95 % (non-condensing).

Operational Advantages
The high MTBF (Mean Time Between Failures) of over 1.6 million hours (MB3170) demonstrates the device’s high reliability. Simultaneous use of serial and Ethernet master access enables flexible network integration. Support for up to 32 TCP clients and 62 serial slaves makes the gateway a scalable solution. Integrated security features such as encryption and authentication enhance network security. DIN rail mounting and robust construction facilitate installation in industrial enclosures.

Scope of Delivery
The device is delivered with a quick start guide and a warranty card. The specified technical data and functions apply to the MB3170-T model. The information refers to the standard version without additional options such as fiber optic connection or galvanic isolation, unless explicitly indicated in the model name (e.g., -I for isolated version). MTBF values are valid for respective models under Telcordia SR332 conditions.

Certifications include EMC (EN 55032/35, FCC Part 15B Class A), environmental (ATEX, IECEx, DNV), safety (UL 60950-1, UL 508, EN 62368-1), and mechanical stress (IEC 60068-2-27/6/32/64). Warranty is 5 years.