• USB-IIRO4-2SM
  • USB Isolated I/O and Serial Communication Board
  • Serial Port Only and Digital I/O Only Versions Available
  • OEM Versions Without Case
  • Multifunction I/O adapter for USB 1.1 and 2.0 port hosts
  • Four optically isolated digital inputs
  • Four Form C electromechanical 1A relays
  • More Features
  • Description
  • Specifications
  • Downloads
  • Ordering Guide
  • Request Quotation
  • The USB-IIRO4-2SM is a USB multifunction device, incorporating a USB 4-port hub internally to provide four optically isolated digital inputs, four electromechanical relay outputs and two ports of RS-232/422/485 serial communication in one small product. The digital portion is ideal for adding easy-to-install isolated input and relay output capabilities to any PC or embedded system with a USB port. This single USB multifunction device is ideal for a variety of applications such as industrial monitoring, control and communication.

    De-populated versions are available with the just the Digitial I/O or the Communcation ports.


    The USB-IIRO4-2SM Features Include:
    • Serial Port Only and Digital I/O Only Versions Available
    • OEM Versions Without Case
    • Multifunction I/O adapter for USB 1.1 and 2.0 port hosts
    • Four optically isolated digital inputs
    • Four Form C electromechanical 1A relays
    • Two serial ports, field selectable RS-232/422/485
    • Small (4"x4"X1.25") rugged industrial enclosure
    • PC/104 module size and mounting compatibility
    • All required power drawn from USB port, no external power adapter required
    • Expansion USB hub port connector
  • Specification
  • Value
  • Bus Interface/Form factor
  • USB2.0
  • No of Digital I/O
  • 4 Isolated in, 4 Relay out, 2xRS-232/422/485
  • Output Type
  • SPDT Electromechanical Relay
  • Input Source Current/Isolation
  • 31VDC/AC
  • Sink Current/Relay Rating
  • 1A 24VDC/0.5A 125VAC
  • Change of State Detection on input
  • Yes
  • Counter/Timers
  • -
  • Connectors
  • DB25 for DI/O, 2xDB9 for serial ports
  • Size
  • 101.6x101.6x31.75(WxDxHmm)
  • Power Requirements
  • USB 5V
  • Data Sheets (pdf)
  • Technical Manuals (pdf)
  • Product Information
  • Internet Links
  • White Papers
  • USB Communication and I/O Devices: USB has become the standard method of connecting peripherals to modern computer systems. Interworld Electronics has an extensive range of USB to Serial Converters, USB Analogue Data Acquisition and USB Digital I/O devices....
  • Media Releases
  • USB Isolated I/O and Serial Communication Board: The USB-IIRO4-2SM provides four optically isolated digital inputs, four electromechanical relay outputs and two RS-232/422/485 serial communication ports. This single USB multifunction device is ideal for a variety of applications such as industrial monitoring, control and communication....
  • Part Numbers
  • USB-IIRO4-2SM
  • USB Isolated I/O and Serial Communication Board
  • USB-IIRO4-DB
  • USB 4 isolated input, 4 relay output unit in a rugged enclosure with screw terminals
  • Options
  • -OEM
  • (USB-104) Board only version (no enclosure or screw terminal board)