USB Relay

USB Relay at a Glance...

  • 16 Relays Installed on a Circuit Board
      - ProXR Expandable to 256 Relays
  • Onboard USB Interface Module
      - Connects Directly to a USB Port
      - Mounts as a Virtual COM Port
  • Industry Leading ProXR Command Set
      - Program in almost any language
      - Send precise commands to control relays
      - Control any or all relays at once
      - Toggle, flash, and timing commands
  • ProXR AD8 Command Set
      - Read 0-5V sensor inputs
      - Monitor external sensors or contact closures
      - Relay Activator: inputs can directly control relays

Selecting the Proper Amperage

To ensure you choose a board with the correct relay amperage for your load requirements, refer to Choosing a Proper Amperage.

This 16-channel USB relay board gives you 16 individually controlled relays and the ability to expand up to 256 relays, making it ideal for scalable automation, industrial control, and custom relay projects.

USB Relay

The USB Relay interfaces directly with a host computer via USB and mounts as a virtual COM port, enabling command-level control of one or more relays on the board. When communicating over USB, all relay commands are transmitted from a virtual COM port over a direct USB connection to the controller, ensuring stable, high-speed data exchange without additional configuration.
USB Relay Switch

Selecting a USB Relay Board Series

The 16-Channel USB Relay Boards are built on the ProXR platform, featuring the industry-leading ProXR Command Set for advanced relay control.

Every ProXR controller is expandable up to 256 relays, making it easy to start with 16 relays today and grow your system as your project evolves.

Expansion boards can be added at checkout or anytime in the future.

Select Your Relay Type & Amperage

Choose the 16-channel USB relay controller that matches your load requirements:
  • SPDT Relays: 5A, 10A, or 20A
  • SPST Relays: 30A
  • DPDT Relays: 1A, 3A, or 5A
Need help selecting the right relay amperage?
Use our Choosing a Proper Amperage to make the right call for your application.
💡 Relay Pros Pro Tip:
Most projects grow over time. With ProXR controllers, you don't have to replace your system - just add expansion boards. Scale from 16 to 256 relays using the same controller, software, and command set.