General
Number of serial ports	16
Serial standards	RS-232, RS-422, RS-485
Data bits	5, 6, 7, 8
Stop bits	1, 1.5, 2
Terminator	120 Ohm
Number of Ethernet interfaces	2
Ethernet isolation	1,5 kV (magnetisch)
Frequency	50/60 Hz
Dimensions (with ears)	480 x 198 x 45,5 mm

The Moxa CN2650-16-2AC is an industrial terminal server with 16 serial RS-232/422/485 ports, designed for applications requiring high reliability and operational safety. The device enables network integration of serial devices in industrial environments, with communication taking place via Ethernet interfaces. The integrated redundancy function with two independent LAN interfaces and two AC power inputs ensures high availability, particularly in safety-critical systems. In the event of failure of a network point or power supply, communication is maintained via the second path. The Redundant COM function enables parallel data transmission over both LAN ports, ensuring stable connection even in case of network failure. Additionally, the terminal server supports the Dual-Host mode, allowing two host PCs to be connected to further increase system availability.

Applications

The CN2650-16-2AC is suitable for industrial applications where serial devices such as measuring instruments, sensors, controls, or printers need to be integrated into a network. Typical use cases include automation systems, building automation, energy supply, transportation technology, and machine construction. The robust construction with metal housing and certifications for electromagnetic compatibility (EMC) and safety make the device suitable for use in harsh environments. The operating temperature range of 0 to 55 °C and humidity of 5 to 95 % (non-condensing) cover a broad range of industrial operating conditions.

Functions and Equipment in Detail

The device features 16 serial ports connected via 8-pin RJ45 connectors. The ports support the standards RS-232, RS-422, and RS-485, with the RS-485 interface operating via ADDC® control. The baud rate can be set between 50 bps and 921.6 kbps, with data bits (5, 6, 7, 8), stop bits (1, 1.5, 2), and parity types (None, Even, Odd, Space, Mark) configurable flexibly. Flow control is managed via RTS/CTS, DTR/DSR, XON/XOFF, or can be disabled. An integrated Watchdog Timer monitors operation and triggers an automatic restart in case of faults. A buzzer and real-time clock (RTC) serve as alarm functions.

Technology Explained Simply

The two Ethernet interfaces (10/100BaseT(X), RJ45) are magnetically isolated at 1.5 kV, ensuring high immunity to interference. Network software functions include configuration via Serial Console, Telnet, Windows Utility, DSU, and Web Console (HTTP/HTTPS). Management protocols include ARP, BOOTP, DHCP, DNS, HTTP, SNMPv1/2c/3, Telnet, TCP/IP, UDP, ICMP, SLIP, and SMTP. Routing is supported via RIPV1/V2 and static routes. Security functions include HTTPS/SSL, SSHv2, RADIUS, PAP, and CHAP. MIB-II support enables standardized network management. Power supply is via two independent inputs of 100 to 240 VAC, 50/60 Hz, with power consumption at 130 mA @ 110 VAC.

Compatibility and Accessories

The terminal server supports a wide range of operating systems, including Windows (95 to 10, Server 2003–2019, Embedded CE 5.0/6.0, XP Embedded), Linux (Kernel 2.4.x to 5.x), UNIX (SCO, QNX, Solaris, AIX, HP-UX), macOS (up to 10.15), and Android (from version 3.1). Driver support enables integration into heterogeneous system environments. Serial signals include TxD, RxD, RTS, CTS, DTR, DSR, DCD, GND (RS-232), Tx+, Tx-, Rx+, Rx-, GND (RS-422), and Data+, Data-, GND (RS-485, 2-wire). RS-485 control is via ADDC®, with integrated pull resistors (1 kΩ, 150 kΩ) and a terminator (120 Ohm). The console port is RS-232 with an 8-pin RJ45 connector (19200, n, 8, 1).

Mounting and Installation

The device is designed for mounting in a 48,3 cm ( 19 inch ) rack. Dimensions are 480 x 198 x 45.5 mm (with mounting ears) or 440 x 198 x 45.5 mm (without ears). Weight is 2,640 g. Installation is performed using the provided mounting ears, designed for securing in standard racks. Power supply is via two independent AC inputs, enabling installation in redundant power supply systems.

Operational Advantages

The CN2650-16-2AC offers high operational safety due to integrated redundancy functions. The MTBF value of 442,699 hours (according to Telcordia TR/SR) demonstrates the high reliability of the device. Comprehensive certification according to EN 55032/24, CISPR 32, FCC Part 15B Class A, IEC 61000-4-2 to -4-11, UL 60950-1, IEC 60068-2-6 (Vibration), and IEC 60068-2-32 (Free Fall) ensures suitability for demanding environments. Warranty is 5 years. Support for many operating systems and protocols facilitates integration into existing IT infrastructures. The Web Console and SNMPv3 support enable centralized network management.

Certifications and Environment

The device meets the requirements of EMC directives EN 55032/24 and CISPR 32, as well as FCC Part 15B Class A. Safety certification is according to UL 60950-1. Mechanical durability is tested according to IEC 60068-2-6 (Vibration) and IEC 60068-2-32 (Free Fall). Environmental certifications include RoHS, CRoHS, and WEEE, fulfilling disposal and recycling requirements. The operating temperature of 0 to 55 °C and humidity of 5 to 95 % (non-condensing) cover typical industrial operating conditions.