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Serial to Ethernet Converter, 2 Ports


SKU: USR-N520 Categories: ,


USR-N520 Introduction Serial to Ethernet Converters

USR-N520 2-port serial to Ethernet servers can realize transparent transmission between TCP/UDP data package and RS232/RS485/RS422 interface.

  • 2-port RS-232/422/485 serial to Ethernet servers.
  • Power supply accepts wide voltage input range DC 5-36V.
  • Support TCP server/client, UDP server/client, https client, Virtual COM.
  • Support Modbus RTU to Modbus TCP.
  • Support flow control CTS/RTS, XON/XOFF.
  • Support 2 RS-232, RS-485/422 3IN1 serial port to 1 10/100Base-T(X) self-adaptive Ethernet interface.
  • Configuration via Web Server page, AT commands, and Windows Utility.

Basic Function of USR-N520

  • Industrial Hardware Design.
    • Industrial solution TI cortex-M4.
    • Hardware Watchdog Design, never crash in 24 hours.
  • Serial Port Switching Among RS232/RS485/RS422
  • Power supply supports Anti-reverse.

Work Mode

  • TCP Server
    • Serial to Ethernet servers USR-N520 listens on the setting port and waits for a TCP client connection.
    • The data which the serial ports sent out transparently.
    • Transmit to all connected TCP clients via USR-N520.
  • TCP Client
    • Serial to Ethernet servers USR-N520 initiates a TCP connection to the set IP address.
    • If the connection fails, USR-N520 will keep trying to reconnect until it succeeds.
    • Once the connection is successful, the data will be transparently.
    • Transmitted between PC and serial device in bi-directional.
  • UDP Mode
    • Serial to Ethernet servers USR-N520 will transmit serial data from serial device to target network device by UDP connection.
    • USR-N520 will listen to port and transmit all received data to serial device.
  • httpsD Client
    • Supports https Client mode which can transmit serial data to the https server in https format(GET/POST).
  • WebSocket
    • Supports WebSocket Sever.
    • Built Websocket link with devices by Websocket of webpage HTML5.
    • Data transmission between built-in webpage and serial port in bi-directional.
    • Custom webpage and websocket are acceptable.
    • Achieves the functions of displaying data in real-time.


  • Socket B function – Serial to Ethernet servers USR-N520 supports the secondary network link, which can send data to two servers. Used for data backup, remote diagnosis, and other requirements.

  • Serial & Network Heartbeat Packet – Network Heartbeat Packet: Serial server maintains the normal connection with the server by sending heartbeat packet regularly. Serial Heartbeat Packet: Serial server informs serial device is active, can be applied in actively catching sensor data.

  • Customize webpage, Synchronized baud rate, net printing, registration package, cloud.


  • Unattended Weighing Systems.
  • Electric Power.
  • Traffic Control.
  • Industrial Automation.


System Information
Processor Cortex-M4
Basic Frequency 120MHz
Flash 512K byte
Port Number 1
Interface Standard RJ45
Rate 10/100 Mbps MDI/MDIX, auto switch between cross and direct connection
Protection 2KV electromagnetism isolation, shell insulation blocking
Network Protocol IP, TCP, UDP, DHCP, DNS, https, ARP, ICMP, Websocket, httpsD Client
Receive Buffer Max 16k bytes buffer
Port Number 2 (RS232/485/422*2), 2 serial ports can simultaneously work at the different working modes.
Interface Standard
RS-485: A+/B-
RS422: TX+/TX-/RX+/RX-
Data Bits 5, 6, 7, 8
Stop Bit 1, 2
Check Bit None, Even, Odd, Space, Mark
Baud Rate 600 bps ~ 230K bps
Flow Control RTS/CTS/Xon/Xoff
Buffer Send and receive 2k bytes respectively
Protection ESD protection, anti-surge
Transparent Transmission Mode TCP Server/TCP Client/UDP Server/UDP Client
Supported Function Networking printing, Modbus Gateway, USR-Cloud, self-defined registration package, self-defined network and serial heartbeat package
SocketB TCP Client/UDP Client
Virtual Serial(USR-VCOM) Windows 2000 or higher (32 bit/64 bit)
Configuration Built-in webpage, computer set-up software, serial command
Basic Parameter
Size 150 x 79 x 30 mm
Operating Temp. -40 ~ 85°C
Storage Temp. -45 ~ 105°C, 5 ~ 95% RH
Input Voltage DC 5 ~ 36V
Working Current
95mA (aver) @ 5V
45mA (aver) @ 12V
Power <1W



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