USB 2.0 to 4-Port RS232-422-485 Serial TB Adapter Isolation | Surge

This optically isolated and surge protected series of Industrial USB 2.0 to 4-port terminal block serial adapter supports RS-232, RS-422, and is DIP switch controlled for each individual port connection to suite the demands of your application.
  • Supports 15KV ESD protection and 600W surge protection for all serial signals
  • Uses FTDI FT4232H USB 2.0 to quad UART chip
  • Incorporates DIP switch control over each individual port.
  • Per port protection from ESD and Surge Protection.
Availability: In stock

4 optically isolated and surge protected terminal block ports

The USB2-4COMi-SI-TB is a USB 2 to 4-port industrial serial adapter that protects you device(s) with optical Isolation, 15KV ESD protection and 600W surge protection over each port. It is designed to make RS-422 and RS-485 serial port expansion quick and simple through its terminal block connection. All ports are controlled by DIP switches, each terminal block serial port can be individually designated for the signal your application demands. The USB 2 to 4-port serial adapter has an industrially designed metal case where the DIP switches are located within the bottom access panel.

By connecting to the USB port on your computer or available USB hub, the USB to industrial serial adapter instantly adds four RS-232/422/485 interface serial communication ports to your system while taking advantage of both the Plug-and-Play, and Hot-Plug features of the USB bus.

The USB2-4COMi-SI-TB industrial serial adapter makes it very easy to add 4 protected industrial communication ports to your system though its terminal block interface with DIP switch controls.


  • Supports USB 1.1 and USB 2.0 transfer speeds from 1.5 up to 480 Mbps, automatic link and speed detection.
  • Adds four high-speed RS-232/422/485 serial ports via USB connection.
  • 2K byte receive buffer.
  • 2K byte transmit buffer for high speed data throughput.
  • Requires no IRQ, DMA, I/O port.
  • Data rates: 300 bps to 921.6K bps.
  • Each serial port supports 5-pin screw-lock-type terminal block connector.
  • Auto-transmit buffer control for 2-wire RS-485 half-duplex operation.
  • Biasing and Termination resistors installed on-board.
  • Supports RS-232 3-wire signals: RxD, TxD, GND
  • Supports RS-422, RS-485 4-wire signals: TxD-, TxD+, RxD+, RxD-
  • Supports RS-485 2-wire signals: data-, data+
  • Monitor LEDS of TxD, RxD indicating port status
  • AC to DC-12V, 1A switching power supply included
  • Supports 3KV optical Isolation, 15KV ESD protection and 600W surge protection
  • Virtual COM port drivers available for Windows 10, 8.1, 8, 7, Vista, 2003, 2000
  • Industrial grade metal case with DIN-rail ears for Din-rail mounting.
  • Chipset: FTDI FT4232H USB 2.0 to quad UART chip
  • Dimensions: 192.42 x 122.22 x 23.60 mm (L×W×H), dimensions are to DIN rail(W), to power plug(L)

Package Contents

  • USB2-4COMi-SI-TB serial adapter
  • Power adapter
  • USB cable
More Information
UPC 736983902443
Color Black
Cable Length 6 feet
Connector(s) Terminals
Warranty One Year
Tech Notes Serial signals RS-232, RS-422, RS-485 are all controlled individually through DIP switches, termination and biasing is also DIP switch controlled, all DIP switches are located under the secure metal plate on the bottom of the chassis.
Compatibility , ,
Material Metal
External Interface USB 2.0
USB Speeds (Mbps) High Speed (480)
Serial Chip FTDI