General
Data bits	5, 6, 7, 8
Stop bits	1, 1.5, 2
RS-485 Pull High/Low	1 kΩ/150 kΩ
RS-485 termination	120 Ω
Ethernet ports	5 x RJ45 (S8455I-Modelle)
Magnetic Ethernet isolation	1.5 kV
Wavelength multimode	1300 nm
RX sensitivity multimode	-32 dBm
RX sensitivity singlemode	-34 dBm
Link budget multimode	12 dB
Alarm outputs	2 x Relais, 1 A @ 24 VDC
IGMP Snooping
LACP

The NPort S8455I-SS-SC from Moxa is an industrial Device-Server with four serial interfaces (RS-232/422/485) and an integrated Managed Ethernet-Switch. The device combines the functions of a serial network adapter with those of a fully manageable network switch in a compact metal housing, suitable for both DIN rail and wall mounting. It is designed for integrating serial devices into IP-based networks, particularly in industrial automation applications where reliable and redundant communication is required.

Applications

The Device-Server is designed for use in industrial environments where serial devices such as sensors, controls, measuring instruments, or machines need to be connected to a network via Ethernet. Integrated redundancy features such as Turbo Ring and Turbo Chain enable network recovery within less than 20 ms, which is crucial for critical applications in manufacturing automation, power supply, or transportation. Support for VLAN, QoS, and IGMP Snooping also makes the device suitable for more complex network structures.

Functions and Features in Detail

The device features four serial ports with DB9 male connectors, supporting all three standards: RS-232, RS-422, and RS-485. The baud rate can be set between 50 bps and 921.6 kbps, with configurable parity (None, Even, Odd, Space, Mark), data bits (5–8), and stop bits (1, 1.5, 2). The serial interfaces are equipped with galvanic isolation of 2 kV, providing high immunity to interference and protection against voltage surges. For RS-485 applications, adjustable pull-up and pull-down resistors (1 kΩ/150 kΩ) and 120 Ω termination are integrated.

Technology Explained Simply

The integrated Managed Ethernet-Switch offers five RJ45 ports (for S8455I models) and two fiber ports with SC connectors, configurable for either multimode or singlemode connections. The fiber ports enable transmission over distances of up to 4–5 km (multimode) or up to 40 km (singlemode). The wavelength is 1300 nm for multimode and 1310 nm for singlemode. The TX power is -10 to -20 dBm (multimode) or 0 to -5 dBm (singlemode), and the RX sensitivity is -32 dBm (multimode) and -34 dBm (singlemode). The magnetic isolation of the Ethernet interface is 1.5 kV, providing additional protection against electrical interference.

Compatibility and Accessories

The device supports various operating modes for the serial ports, including Real COM, RFC2217, TCP Client/Server, UDP, and Disabled. Network management is performed via WebGUI, Telnet, SNMPv1/2c/3, RMON, and LLDP. Additional features include Port Trunking, DHCP Option 82, VLAN, QoS, and IGMP Snooping. The integrated digital inputs (2x, active at +13 to +30 V) and alarm outputs (2x relays, 1 A @ 24 VDC) allow integration into monitoring and alarm-based systems. Power supply is via 12–48 VDC, with redundant power supply possible through two separate connectors.

Mounting and Installation

The device is housed in a robust metal enclosure with dimensions 73.1 x 134 x 125 mm and can be mounted on DIN rails or on a wall. Power supply is via two removable 6-pole terminal blocks. Power consumption is 935 mA at 12 VDC. Operating temperature ranges from -40 °C to 75 °C, and humidity from 5 % to 95 % (non-condensing). Certifications include EMC standards such as EN 55032/24, FCC Part 15B, CISPR 32, as well as safety standards such as UL 508, EN 60950-1, and IEC 60950-1. Environmental resistance is ensured by certification according to IEC 61000-4-x and IEC 60068-2-x, as well as classification Class I Division 2 (C1D2). The MTBF is up to 287,354 hours depending on the model.

Operational Advantages

The combination of serial ports and Managed Switch in a single device reduces cabling effort and the number of required devices. Integrated redundancy protocols ensure high availability, while comprehensive management functions enable flexible network control. Galvanic isolation and overvoltage protection functions increase reliability in electrically harsh environments.

Scope of Delivery

The scope of delivery includes 1 x NPort S8000 device server, 1 x quick installation guide, and 1 x warranty card.