General
Number of serial ports	2
Data bits	5, 6, 7, 8
Stop bits	1, 1.5, 2
Relative humidity	5–95 %
MTBF	639.622 Stunden
PCB conformal coating
UDP multicast

The Moxa NPort 5250AI-M12-CT is a 2-port device server for serial interfaces in industrial and railway applications. It enables the integration of RS-232/422/485 devices into Ethernet networks and is specifically designed for applications in the railway industry, where high mechanical stress, vibrations, and strictly defined environmental conditions prevail. The device complies with railway standards EN 50155 and EN 50121-4, which define requirements for temperature, voltage, shock, ESD, vibration, and electromagnetic compatibility. Compliance with these standards makes the NPort 5250AI-M12-CT suitable for use in rolling stock and wayside installations.

Applications

The NPort 5250AI-M12-CT is designed for industrial environments where robust, reliable, and low-maintenance communication solutions are required. Typical applications include networking sensors, control devices, operator panels, or other serial end devices in railway installations, such as signaling systems, train control systems, or monitoring units. The M12 connectors and IP40 metal housing ensure high mechanical stability and protection against dust and splashing water, making it suitable for outdoor use, provided there is no direct moisture or high humidity.

Features and Equipment in Detail

The device features two serial interfaces with DB9 male connectors, which can be configured as RS-232, RS-422, or RS-485 (2- or 4-wire) as required. The baud rate can be set between 50 and 921.6 kbps, with flexible settings for data bits (5–8), stop bits (1, 1.5, 2), and parity types (None, Even, Odd, Space, Mark). Flow control is supported via RTS/CTS, DTR/DSR, or XON/XOFF. Automatic RS-485 control (ADDC) supports bidirectional communication without additional control logic. The serial signals are galvanically isolated at 2 kV, enhancing noise immunity and preventing damage from voltage surges.

Technology Explained Simply

The NPort 5250AI-M12-CT connects serial devices over an Ethernet network, making them accessible via TCP/IP protocols. The Ethernet interface uses an M12 D-coded 4-pin female connector, which is robust and easy to wire for industrial applications. Power supply is provided via an M12 A-coded 5-pin male connector, operating within a voltage range of 12 to 48 VDC, with EN 50155 compliance for 24/48 VDC. Power consumption is 360 mA for two ports. Configuration is performed via a web-based interface, Telnet, Windows Utility, DSU, or MCC Tool. The devices support protocols such as TCP, UDP, DHCP, DNS, ARP, LLDP, SMTP, ICMP, and SNMPv1/v2c/v3. Security features include HTTPS, AES-128 encryption, RSA-1024, SHA-1/256, and TLS 1.2. The Real COM/TTY function enables the use of serial ports as virtual COM ports under Windows, Linux, macOS, UNIX, and Android.

Compatibility and Accessories

The NPort 5250AI-M12-CT is compatible with a wide range of operating systems, including Windows, Linux, macOS, Android, and various UNIX systems. Support for COM port grouping and UDP multicast expands application possibilities in complex networks. The devices can be integrated into existing Ethernet infrastructures, with M12 connections ensuring secure and reliable connectivity. The CT version of the device features PCB conformal coating, providing additional protection against moisture, dust, and chemical influences.

Mounting and Installation

The device is housed in a robust metal enclosure with IP40 protection rating and can be mounted on a wall or inside an enclosure. Mounting is done using integrated mounting elements. Commissioning is possible within 30 seconds thanks to the web-based 3-step configuration. Connectors are clearly labeled, with serial ports using DB9 male connectors and Ethernet and power connections using M12 connectors. Power supply is via the M12 A-coded connector, requiring a voltage range of 12 to 48 VDC.

Operational Advantages

The NPort 5250AI-M12-CT offers high operational reliability due to galvanic isolation, robust construction, and compliance with railway standards. The web-based configuration and extensive diagnostic and security functions simplify maintenance and monitoring. SNMP alarm support enables proactive fault detection. The MTBF (Mean Time Between Failures) is 639,622 hours, indicating high reliability. The operating temperature range of -25 to 55 °C and relative humidity of 5–95 % (non-condensing) allow use in a wide variety of environments. The CT version with PCB conformal coating provides additional protection against environmental influences.

Scope of Delivery

The device is delivered with a quick start guide and a warranty card. The guide supports rapid commissioning and configuration of the device. The warranty card documents the manufacturer’s warranty terms. Batteries are not included.