Product was successfully added to your shopping cart.

Go to cart page

You have successfully subscribed to this product. You will receive an email when the product is in stock.

Velleman K8090: 8 Channel USB Relay Card Kit

Velleman K8090: 8 Channel USB Relay Card Kit

Velleman K8090

Velleman K8090: 8 Channel USB Relay Card Kit (Electronic Project Kit - Soldering Required)

The Velleman K8090 8-Channel USB Relay kit is a USB device that communicates over a virtual serial port (COM) that allows you to control 8 different relays. The relays can be set for toggle, momentary or timer operations (selectable through the software). The downloadable Velleman software package is free and includes a DLL (dynamic link library) so you can develop your own software. The software package also includes examples, help files, protocol manual and a test program to get you started. The Velleman K8090 is event-driven and open protocol with two way PC communication (USB event return). You can use the on board push buttons to test or operate the relays. There is an on board connector for open collector connectivity (push button simulation) and board space provided to install VDR noise suppressors.


  • Power supply for relays: 9-10Vac or 12 to 14Vdc (500mA)
  • 8 high-power relays: 16A each (resistive load)
  • Dimensions: 160 x 107 x 30mm / 6.3" x 4.2" x 1.2"
  • Minimum system requirements:
    • PC running USB compatible Windows version
    • USB1.1 and USB2.0 full speed compatible
    • Internet connection for software download

Additional Information

Difficulty Level 5


Parts list
English assembly instructions through illustrations, pictures, etc.

Assembly instructions
Written multilingual manual explaining how to build the kit


Server application (Windows) for the Mobile K8090 iOS app
Install this server to use your iPhone or iPad to operate your K8090 with the [link url=http://itunes.apple.com/us/app/mobile-k8090/id456579604?mt=8]Mobile K8090[/link] app available on iTunes.

Server application (Windows) for the K8090 Remote iOS app
Install this server to use your iPhone or iPad to operate your K8090 with the [link url=http://itunes.apple.com/us/app/k8090-remote/id503106849?ls=1&mt=8]K8090 Remote[/link] app available on iTunes.

Software package for K8090, build 100820
Getting started guide,protocol manual,drivers,DLL with VBexpress 2008 .net example,standalone test/demo software. Download and install this software before using our K8090.

Velleman Kits USB driver
Generic driver for the following range of products: K8090, K8019, K8018, MK193, K8101, K8097 and K8096. This driver is compatible with both 32-bit and 64-bit versions of Windows (2000/XP/Vista/7/8).

Info Sheets

Resistor colour code

Product information

Overview of Velleman modules that are equal to D.I.Y Kits
This sheet is useful when you want to know which modules you could find in the do-it-yourself range of Velleman Kits and minikits.

 Warning: this product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to: www.P65Warnings.ca.gov/product