Updated: 08.11.2026
Many building owners want to open windows not only with a push button but also via their smart home: by time of day, room temperature or weather. This works well with electric window drives as long as the control matches the drive voltage. Here you can read which options exist and what you need.
In brief: 230 V drives are controlled like a roller shutter via an actuator with up/down outputs. 24 V drives open and close by reversing polarity, so you need a suitable controller or a polarity-reversing relay. Drives of the i series can be controlled directly via Modbus. Our controllers do not have a KNX interface.
Three ways into the smart home
| Way | Suitable for | What you need |
|---|---|---|
| Shutter actuator (up/down) | 230 V actuators | Actuator with two mutually interlocked outputs |
| Polarity relay or controller | 24 V actuators | 24 V power supply and a circuit that reverses polarity |
| Modbus | i series drives | Gateway or smart home system with Modbus |
230 V drives: like a roller shutter
A 230 V window drive has one wire for open and one for close. It can therefore be switched with the same actuators as a roller shutter motor. Important: both outputs must never be live at the same time. Shutter actuators are interlocked for this. In your smart home system, choose the device type “shutter” or “cover”.
24 V drives: reversing polarity instead of two wires
24 V drives open when plus and minus are applied one way and close when the polarity is reversed. A simple switching actuator is therefore not enough. You need a polarity-reversing relay or a controller such as the VS-C24-7A, which converts 230 V to 24 V and supplies up to 7 drives.
The VS-C24-7A is operated with a button on the unit or by radio remote control. We are happy to clarify in advance whether and how you can connect it to your smart home.
i series: directly via Modbus
The smart drives of the i series, for example the VS-KA-i, have a Modbus interface. This allows them to be controlled directly from a building management system or a smart home system with Modbus. More in the guide Integrating window drives into building management systems.
Safety: rain, wind and pinch points
- Plan a rain or wind and rain sensor so that open windows close when the weather changes. More on this: Rain sensor for windows
- Automatically moving windows can trap fingers. Check the closing edges, especially on low windows.
- Always combine smart home rules with a local push button so the windows can also be operated without the app.
Frequently asked questions
Can I control a window drive with Home Assistant?
Yes. 230 V drives are connected via a shutter actuator, 24 V drives via a polarity relay or a suitable controller, and i series drives via Modbus.
Do the controllers have a KNX interface?
No, our controllers do not have a KNX interface. In KNX systems, 230 V drives can be switched with a KNX blind actuator.
Which voltage is better for a smart home?
With 230 V, connection is often simpler because common shutter actuators fit. 24 V is practical when several drives and sensors share one controller. We are happy to advise you via the Project enquiry.
Technically reviewed by Dietmar Heiken, Sales, Vent Systems HDI GmbH, Hamburg – around 20 years of industry experience. Questions? Phone +49 40 50694631 or info@ventsystems.de
Last updated: 08.11.2026
Questions? 040 50694631 · info@ventsystems.de
