This low cost, general purpose, USB powered board has four opto-isolated relays and four general purpose digital I/O channels.  The relays and PCB tracking are designed to handle 240VAC@10A. This board is fitted with 6V operating relays for low power consumption at 5V from either USB or external supply.

Access to all relay contacts and the 4 DIO channels is via fixed screw terminal block connectors along the edge of the card.  Suitable for a wide range of control and mains voltage power switching purposes, it also offers screw terminal access to the USB power connections for possible onward powering/use in your target system . 

The board comes with +5V & relay channel LED status indicators.  Nylon feet are fitted in each corner which will take self tapping screws.  They can easily be removed to allow the cards to be mounted on pillars or stacked. There is also a perspex cover available which offers general protection of the card and prevents accidental contact with any of the relay contacts or screw terminal connections.  In addition, there is a DIN rail mount/cover option available.

These are industry standard relay boards and products.  High quality, for professional electronic  automation,  connectivity, and control.

Easydaq products are used in research and education, security, industrial applications, power and energy management,  motor and device  control. There are uses across various industries, including  maritime , rail,  automotive, automation, measuring and calibration, agriculture , medical, sanitation, light and power solutions, fire protection, security, and many more.

You can order any of our boards with customisations or without connectors fitted - contact us for prices

Download datasheet

Quickstart Guide

EasyDAQ is primarily a business-to business seller, supplying products around the world, therefore advertised prices exclude VAT. Customers in the UK and Northern Ireland will be charged VAT  at checkout. 

Operational Parameters
Control Interface USB
Relay coil voltage 6V
Relay Channels 4
Relay contact current 10A
Digital input channels 4
Relay Type POWER
Digital output channels 4
Opto-isolated YES


  • Brand: Easydaq
  • Product Code:USB4PRMx
  • Availability:In Stock
  • £52.00

  • 10 or more £41.60
  • 25 or more £36.92
  • 50 or more £34.63
  • 100 or more £32.55
  • 250 or more £30.42
  • 500 or more £28.18

Related Products



CoverUSB4MxDIN A Perspex cover for 4-relay boards with single part connectors. Contact us fo..




A Perspex cover for the 4-relay boards with single part connectors. Contact us for more inf..




Recommended for use across relay contacts in 120/240VAC mains switching applications.  (Minimis..


Tags: Power, 4-relay, relay, board, USB, USB4PRMx, EasyDAQ, UK, RoHS, CE, 3TG,