• us 346 usb 4 port rs422 485 1mbaud
  • US 346 RS 422 485 Pinout
us 346 usb 4 port rs422 485 1mbaud
  • 4 Port RS-422/485 USB to Serial Server
  • Data rate from 300 to 921,600 baud
  • High Retention USB Socket, IP30 Rated Case
  • Drivers for all popular operating systems including Windows 8
  • Screw Lock Power Supply (included)
  • Lifetime Warranty and Support
  • US-346-datasheet (0.79 MB)
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USB to Serial server providing four RS422/485 serial ports. Data transfer rates up to 921,600 baud rates and the 128 byte deep transmit and 256 byte receive FIFOS, coupled with 1Mbit line drivers deliver uncompromising performance on your laptop/PC.

Drivers for Windows 32 bit and 64 bit Operating Systems including Windows XP, Server 2003, Vista, Server 2008, Windows 7 and Windows 8 with additional drivers for both Mac OS X and Linux.

* Please note Brainboxes USB to Serial RS422/485 products have a known issue when used in Windows 10 and attempting to configure to be used in half duplex mode. This mode is currently unavailable in Windows 10.

Customer Feedback

Operating Systems

Tech Spec

Serial Port
ConnectorDB9 Connector - 9 Pin Male
Tx FIFO Size128
Rx FIFO Size384
Operating DistanceRS422/485 Standard (4000 ft : 1200 metres)
CableUSB cable Type A to B (1 metre ~ 3ft)
Serial Port Settings
Max Baud Rate921,600
Data Bits7 or 8
ParityOdd, Even, None, Mark or Space
Stop Bits1 or 2
Tx/Rx ModesFull Duplex, Half Duplex Autogating
Power Input5V DC input
Power Supply 1 DescriptionGlobal Power Supply - PW-500
Power Supply 2 Description
Mounting Accessories 1 DescriptionWall Mounting kit for 4&8 ports - MK-059
Mounting Accessories 2 DescriptionSnap In DIN Clip kit for 4&8 ports - MK-070
PCB Layers4
Device Dims with ears96.3x101x25
Device Dims without ears91.6x77x25
Industrial StandardYes
Power Consumption[email protected]
Product Weight0.675 kg, 23.81 ounces
Product Dimensions215x123x34 mm, 8.5x4.8x1.3 inches
Packaged Weight1.100 kg, 38.80 ounces
Packaged Dimensions300x135x80 mm, 11.8x5.3x3.1 inches
GTIN (barcode)837324002096
Operating System Compatibility
Operating Systems
  • Microsoft Windows 10
  • Microsoft Windows 8 32 bit & 64 bit Editions
  • Microsoft Windows 7 32 bit & 64 bit Editions
  • Windows Server 2008 32 bit & 64 bit Editions
  • Windows Vista 32 bit & 64 bit Editions
  • Mac OS X
  • Windows XP 32 bit & 64 bit Editions
  • Linux
USB 2.0480 Mb/s USB 2.0 data rates.


Microsoft Signed Drivers

Microsoft Hardware