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For shipping to USA, Canada and Mexico only. Please send inquiries to for the rest of Americas.
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For shipping to USA, Canada and Mexico only. Please send inquiries to for the rest of Americas.
Please visit for other regions.

USB to RS232/RS422/RS485 adapters (FULL SPEED)

SKU ES-U-3001-MB

Our USB to RS232/RS422/RS485 adapters are an easy way to connect serial devices to a USB port on your computer. They support RS232, RS422 and RS485 modes.

These adapters offer a great deal of flexibility as they can be switched to RS232, RS422 or RS485 mode and so are suitable for a wide range of applications. Each port has options such as termination and biasing for RS485 and indication LEDs for Power, Tx and Rx for easy diagnostics.

The single-port model can be switched to RS232, RS422 or RS485.

On the 8-port and 16-port versions, each port can be switched to RS232, RS422 or RS485 modes individually allowing a mixture of devices to be connected.

With their multiple serial modes and easy to install drivers for a range of operating systems, these adapters are ideal for adding one or more RS232/RS422/RS485 ports to your computer.

  • Based on the renowned FTDI USB-Serial chipsets and drivers
  • Microsoft Windows® WHQL-certified, macOS and Linux drivers
  • Each RS232/RS422/RS485 port can appear as a Virtual Com Port allowing easy use with existing application programs
  • Multi-port units create a separate COM port for each port with separate settings (such as baud rate and flow control) per port
  • Ports can also be accessed using the FTDI D2xx DLL functions
  • Signals (note that access to the signals depends on the connector type)
    • RS422: TxD+, TxD-, RxD+, RxD-, GND, RTS+, RTS-, CTS+, CTS-
    • RS485 4-wire: TxD+, TxD-, RxD+, RxD-, GND
    • RS485 2-wire: Data+, Data-, GND
    • RS232: TxD, RxD, RTS, CTS, DSR, DTR, DCD, RI, GND
  • RS232/422/RS485 signals via DB-9 connectors
  • Terminal Block also available on single port model (subset of signals)
  • Automatic Hardware (RTS / CTS) flow control on RS232/RS422 models on DB-9
  • Software (X-on/X-off) flow control
  • Power and Tx/Rx LED indicators help to confirm operation and assist in troubleshooting
  • Available in 1, 8 and 16-port versions
  • USB Type-B connector
  • 1-port model has a compact metal enclosure and is powered from USB
  • 8-port and 16-port models are rack-mountable with Internal mains PSU

Feel free to browse through the corresponding datasheet for more information.

Part Number Document Type Version File
ES-U-3001-MB  ES-U-3008-RM
Manual 2.2 Download
All Products Drivers Installation Guide 1.0 Download

Download Virtual COM Port (VCP) Drivers for Windows, Mac OS and Linux

Order Information
SKU Ports Housing Connector


(Updated version from ES-U-3001-M [USB-COMi-M] to support higher data throughput)

Din Rail Bracket (DR-201) the rank mount clip is available for sales. if required, please contact us at

1 Metal USB-B 
ES-U-3008-RM 8 Metal USB-B 
ES-U-3016-RM 16 Metal USB-B