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National Control Devices, LLC


USB Relay Controllers

USB Relay

USB Relay Control

USB RelayUSB Relay Controllers allow computer controlled switching using the USB port of your computer.  An NCD USB Relay Board emulates a COM port, allowing you to speak to the relay board using any programming language that supports serial communications.  COM drivers allow you to assign any COM port to the USB Relay Board.  Many of our relay boards support 8-Channels of 8-Bit / 10-Bit Analog to Digital Conversion (A/D), and can be expanded to control more relays as your needs grow.

No programming is required with the new Reactor Series, Key Fob Series and Time Activated Relays!  No computer is required once the board is configured to your needs either!  Our free configuration utility allows you to simply configure the board and your done!

All the Features You Need

  • USB Interface mounts as a Virtual COM Port on your PC for easy programming and 100% compatibility across ALL operating systems
  • Plug in, open the Virtual COM Port, and start sending commands
  • 1, 3, 5, 10, 20 or 30 amp relays available
  • Control one relay at a time or all relays at once
  • SPDT, SPST, DPDT and Reed Relay versions available
  • Many Series Available
    • Computer/Software Control with ProXR, ProXR Lite, and Fusion Series
    • Handheld Remote Key Fob Control with Key Fob Relays
    • Sensor Automated Control with Reactor and Fusion Series
    • Time Automated Control with Taralist and Fusion Series
    • Point to Point Contact Closure driven Relays with MirC, MirX, MirW and MirM

USB Relay Boards:

Our USB boards offer your choice of 1, 3, 5, 10, 20 or 30 amp relays and are available in many channel versions with many series supporting Analog to Digital Conversion on Board. Computer Controlled USB Relays feature the ProXR Command Set allowing for a unified API to control all relay controllers. Other Series use a configuration software to let you tell them how and when they should automate relays based on time and/or sensors.

Learn More:

USB Relay Controllers: Choosing the Right Controller
Learn to Use ProXR Series Controllers
Learn about Other Interface Options, Including IoT, Ethernet, WiFi, Bluetooth, and More