A 24 V window actuator must never be connected directly to 230 V . It needs a controller or power supply that converts the mains voltage into 24 V DC. This article shows how it works, how many actuators one controller can supply and what to look out for with cables and accessories.
In brief: A 24 V window actuator must never be connected directly to 230 V. It needs a control unit or power supply that converts 230 V into 24 V DC, for example the VS-C24-7A with 7 A output current. How many actuators it can supply depends on the sum of their current draws.
How it works
the VS-C24-7A controller is connected to 230 V AC and supplies 24 V DC to the actuator. The direction of travel is set by reversing polarity: swap plus and minus and the actuator runs the other way. It is operated via a button on the unit or by radio remote control.
How many actuators can one controller handle?
What counts is the current. Add up the current consumption of all actuators running at the same time and compare the total with the output current of the controller. An example:
- actuators VS-CKA 300 or VS-SB 400/90: 1.2 A each
- VS-C24-7A: 7 A output current
- Mathematically this is enough for 5 actuators (6 A); but plan some reserve
You can find the current consumption of your actuator in the data sheet on the product page under “Downloads”.
Choosing the right cable
At 24 V more current flows than at 230 V. On long cable runs, noticeable voltage is therefore lost and the actuator runs more slowly or stops. Choose a larger cable cross-section for longer distances. Installation on the 230 V mains is carried out by a qualified electrician.
You can estimate the required cross-section for copper cables with this approximation:
A = (2 × L × I) ÷ (56 × ΔU)
A is the cross-section in mm², L the single cable length in m, I the sum of the actuator currents in A and ΔU the permissible voltage drop in V according to the actuator or control unit manufacturer. Choose the next larger standard cross-section. Example: a 25 m cable, 3.2 A and a permissible voltage drop of 1.2 V give around 2.4 mm², so 2.5 mm² is chosen. For smoke ventilation systems, the circuit integrity requirements of the fire safety concept also apply.
Push buttons, radio and sensors
- Push button: to open and close at the push of a button, e.g. VS-LT-A surface-mounted push button
- Radio: VS-C24-F-1 hand-held transmitter with wall holder
- Rain and wind: VS-RS rain sensor or VS-WRLS-wind-rain-light sensor close the windows automatically
How to combine push buttons, controllers and sensors sensibly is shown in the guide Ventilation control for window actuators. The VS-C24-7A is also suitable for blinds and roller shutters: 24V blind control.
Rather go straight for 230 V?
230 V actuators are connected without a controller directly to a Ventilation button . In return, 24 V actuators are more flexible with sensors, radio and synchronous operation. The detailed comparison: Window actuator 24 V or 230 V.
Important for SHEV
The VS-C24-7A is intended for everyday comfort ventilation. For smoke and heat exhaust, an approved SHEV control panel is required, see RWA.
Frequently asked questions
What happens if I connect a 24 V actuator directly to 230 V?
The actuator is usually destroyed immediately, and mains voltage poses a hazard. A 24 V actuator must always be connected to a control unit or power supply with 24 V DC.
Is a standard 24 V power supply enough?
Only to a limited extent. The power supply must deliver DC voltage and enough current for all actuators running at the same time. In addition, the polarity must be reversed to open and close. This is done by a control unit or a suitable push button. A ready-made control unit such as the VS-C24-7A is simpler.
Consultation and offer
Send us dimensions, weight and a photo of your window, we will check the force and suggest the right actuator. Phone 040 50694631 (Mon–Fri 8 am–5 pm), Contact form or measurement sheet.
Further reading: Window actuator: 24 V or 230 V? · Ventilation controls