Control Velux io-homecontrol® products via FS20

I always wanted to connect my Velux electrical shutters with my HomeAutomation system. The solution Velux proposes is as follows; buy a KLF 100 (250 €) per electrical shutter (in fact you could also build some groups, but who wants to limit the flexibility) and don’t forget you also need an actuator from your HomeAutomation system to steer the KLF interface.

7 * KLF 100  (250 € each) = 1750,00 €                                                                                    4 * FS20 EM4 (18,95 € each) = 75,80 €

Obviously this is a bit expensive, there must be a different way. For every electrical shutter I already have a Velux KUX 100 (the basis electric control unit) in place, which comes with a small remote control. So I decided to use those remotes together with the above mentioned FS20 EM4 as the basis for my tinkering.


The whole installation has found its place in an ikea plastic box.

I stripped the remotes from their casings, modded them to run with an external power source and connected both pins from the up / down butt contacts with cables which will be used to solder it to the FS20 module.

FS20 EM4 connected to Velux remote control

Each FS20 EM4 module is capable to control 2 Velux remote controls if you only want to control the up and down button. Why this is sufficient will be explained in a second.

The remote knows two operational modi:

  1. short press on the button, the shutter moves into the desired direction until it reaches the final position
  2. constant press on the button, the shutter moves into the desired direction until it reaches the final position or until the button is released

The emulation of the 1st modus has turned out not to be sufficiently reliable, therefore I decided to switch the buttons on for 50 seconds (the shutter will need between 45 and 48 seconds from final position open to final position closed and vice versa). To stop in between the final positions I simply switch off the button and the shutter stops. One of the further advantages of this approach is that the use of the remote controls stop button is not required.

Supply lines on the back side

On the back side of the box I placed the supply lines:

  • 5 Volt for the FS20 Modules
  • 3 Volt for the Velux remote controls

In a next step I also want to connect to Somfy remote controls following the same principle.