USB Relay

USB Relay Switch at a Glance...

  • 8 Relays Installed on a Circuit Board
      - ProXR Lite Not Expandable
      - ProXR Expandable to 256 Relays
  • Onboard USB Interface Module
      - Connects Directly to a USB Pport
      - Mounts as a Virtual COM Port for Seamless Integration
  • Industry Leading ProXR Command Set
      - Compatible with Almost Any Programming Language
      - Send Precise Commands to Control Relays
      - Supports Toggle, Flash, and Timing Operations
  • ProXR AD8 Command Set
      - Reads 0 - 5V Sensor Iinputs
      - Monitors External Sensors or Contact Closures
      - Direct Relay Control Via Input Signals

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.

Looking for an 8-channel USB relay board? Choose from expandable ProXR models, non-expandable ProXR Lite versions, and DPDT relay options for advanced switching needs.

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

Take Control with 8-Channel USB Relay Switches

8-channel USB relay boards are available in ProXR Lite and ProXR versions:
  • ProXR Lite - Non-expandable, streamlined design
  • ProXR - Expandable up to 256 relays
Both versions use the same firmware and support the full ProXR Command Set, giving you identical control capabilities. The difference is expandability.

Select Your Relay Type & Amperage

Choose the 8-channel USB relay controller that matches your load requirements:
  • SPDT Relays: 5A, 10A, or 20A
  • SPST Relays: 30A
  • DPDT Relays: 1A, 3A, or 5A (ProXR only)
Need help selecting the right relay amperage?
Use our Choosing a Proper Amperage to make the right call for your application.
ProXR Lite vs ProXR
  • ProXR Lite: Non-expandable, streamlined design for fixed-size projects
  • ProXR: Expandable up to 256 relays for growing systems
  • Both: Same firmware, same ProXR Command Set, same control features
💡 Relay Pros Pro Tip:
If you think your project might grow, choose the ProXR version. You'll start with 8 relays today and expand up to 256 later - without replacing your controller.