Leading Edge Networking Solutions


1-Port Industrial Secure Modbus TCP/RTU/ASCII Gateway, DIN-rail mount, wide-temperature


Diverse Hardware Infrastructure
Modbus Gateway supports the four most commonly used communication standards, RS-232/485/422, and Ethernet. The ease-ofuse configuration utility provided with Modbus Gateway can quickly select the hardware interface , and easily switch to the existing communication infrastructure. Industrial EMC protection and wide temperature operation capability make MB5901 ready for every mission. And if cabling is an issue, the PoE-powered version can allow MB5901 to be powered through PoE.

Embedded Security
MB5901 Modbus Gateway supports IPsec VPN encryption, allowing you to safely use the device over the internet without worrying about malicious attacks, data sniffing or unintentional remote control of your Modbus slaves. The embedded VPN deamon supports peer-to-peer and peer-to-side connections.

Switching between Modbus Protocols
Modbus Gateway supports the standard Modbus protocol and is capable of converting any Modbus protocols between Modbus TCP, Modbus RTU, and Modbus ASCII for all supported hardware interfaces.

Modbus ID Routing
Modbus Gateway supports various types of hardware communication interfaces, Modbus protocol conversion, and Modbus ID routing. Therefore the Modbus Gateway can integrate your existing and complex Modbus hardware configuration into a simple network that can be easily managed.
MB5901 large


  • Bi-Directional Modbus TCP/RTU/ASCII conversion from Serial to Ethernet and Vice-versa
  • Industrial-grade hardware for operating in harsh environments
  • Wide temperature range for operations at extreme temperatures
  • Advanced features include embedded IPsec VPN security, Virtual ID remapping, VirtualCOM mode, exception handling and many others
  • 2 x 10/100 Mbps Ethernet port, 1 x RS-232/485 port,up to 921.6 Kbps
  • Embedded IEEE802.1D-2004 RSTP Redundancy
  • Configuration via Web Browser / Serial-Telnet Console / Windows Utility
  • Optional 802.3af PoE models can be powered through the Ethernet cable

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MB5901 application  MB5901 Series

MB5901-DB - 1x RS232/422/485 (DB9M)+ 2x 10/100Base-TX (RJ45)

MB5901-TB - 1x RS232/422/485 (TB)+ 2x 10/100Base-TX (RJ45)

MB5901-PoE-DB - 1x RS232/422/485 (DB9M)+ 2x 10/100Base-TX (1x PoE PD - RJ45)

MB5901-PoE-TB - 1x RS232/422/485 (TB)+ 2x 10/100Base-TX (1xPoE PD - RJ45)

Serial RS232

  • Serial Baud Rate: 1200 bps to 921 Kbps
  • Data Bits: 7, 8
  • Parity: odd, even, none, mark, space
  • Stop Bits: 1, 2
  • Signals: TxD, RxD, RTS, CTS, DTR, DSR, DCD, RI, GND
  • flow Control: XON/XOFF, RTS/CTS, DTR/DSR


  • 9~48 VDC power input at 3-pin terminal block
  • PoE 802.3 af Powered Device
  • Overload Current Protection Present

Operating Temperature: -40 to 85°C
Operating Humidity 5% to 95% Non-condensing

Warranty 5 years


MDR-45 series DIN-Rail power supply


  • Protocols: IPv4, ICMP, TCP, UDP, DHCP Client, SNMPv1,v2c,v3, HTTP, HTTPS, Telnet, RFC2217, RSTP, Security via OpenVPN Client/Server or IPsec VPN (peer-to-peer or peer-to-side) with up to 37.9Mbps VPN throughput, PPTP, and SMTP/TLS
  • Management: Web, Device Management Utility, Telnet, SNMPv1/v2c/v3, SMS
  • Virtual COM: Windows/Linux redirection software
  • Modbus Gateway Supported Modes: Ethernet: Modbus TCP Server/Client(or VCOM); Serial: Modbus RTU/ASCII (master/slave)
  • Maximum number of Modbus clients/slaves: Modbus TCP: Maximum 16 clients; Maximum 32 slave connections