Integrating Somfy RTS Blinds with KNX

When controlling blinds or curtains it is always advisable to use wired solutions as this provides the most flexibility and reliability. There is a KNX solution for any type of wired motor from basic 230v motors all the way up to digital control solutions, such as SMI or Somfy Digital Networks.

However, sometimes the blinds are installed after the building works are completed, or it’s just not possible to run cables to the windows. For these instances, Somfy have a proven wireless solution that uses battery-powered motors. The RTS solution can also be used where power is available but there aren’t enough cables for control. There is even a battery-powered option for when a completely wireless solution is required.

Thankfully it is possible to integrate Wireless RTS Motors with KNX using devices from Somfy that convert inputs or RS485 Commands to wireless RTS commands. These can be used to control single blinds/curtains or groups, meaning only one interface may be needed to control all the blinds or curtains on a Façade. The interface will need to be in range of the motors (approx. 20m), so this may influence how many are needed.

There are two interface models from Somfy. The first is a single channel device that can easily be mounted discretely near the motors. View online here The second is larger so will need more planning on its location. It offers 5 inputs and the option to use RS485 to control up to 16 motors. View online here

From the KNX side, you will need two standard relay outputs for each motor or group you are looking to control. To use the RS485 input a KNX-RS485 interface is required, though this is a more advanced method of control and thus is only recommended for integrators experienced with serial control.

User Interface Options

Now the motors can be controlled it’s time to consider the user interface options from KNX. If you already have keypads in the room configuring the buttons for blind control is straight forward, though as it's not native KNX motor control you may need to use two buttons to achieve the desired level of functionality.

Control from KNX touch screens and apps is also possible, as is voice control from Amazon Alexa, Google Home and Apple Homekit with a suitable voice control to KNX gateway such as the ABB Busch-VoiceControl

Helioscreen

If you’d like to be able to provide a complete solution including the blinds themselves, Helioscreen is a great option, and is available in wired, wireless and manual options allowing you to match the blinds through an entire project regardless of the availability of cabling or the required functionality.