What is a window actuator?
An actuator is a type of motor for moving or controlling a mechanism or system. It is operated by a source of energy, usually an electric current, hydraulic fluid pressure or pneumatic pressure. It then converts that energy into motion. In building services engineering there are two types of actuator commonly used;
- Valve actuators for controlling valves within BMS systems
- Actuators for controlling ventilation equipment or automatic opening windows
SCS Group, as a control and fire engineering specialist provides both types of actuator. The BMS type is provided as part of the design and installation service for control systems.
Actuators for smoke control are part of a system containing 3 elements: A trigger, an actuating mechanism and a power source. The trigger for automatic opening systems will usually be a smoke detector. A range of smoke detectors are available from the Easivent online shop.
Commonly used actuators
The most commonly used window actuators are the chain drive (pictured below), the linear actuator and the folding arm. The selection is dependent on the stroke required to open the window (or ventilator) to achieve the required free area. It is also important to consider the power needed, the angle of installation and the hinge position.
For most smoke control uses a back up power supply is required. Most commonly this is a battery back up system with 24V actuators, although it is possible to use Uninterruptible Power Supplies and 230V actuators. A packaged local control panel designed for use with AOV’s is the easiest way to achieve a Building Regulations compliant solution.
An override switch for testing and for Fire Brigade use is also a requirement of building regulations as this is often the only operator facility for the system. It is useful to have some system status indication and warning alarms for fault or loss of power to ensure the system is maintained correctly.
For environmental ventilation systems, actuators are similar to those used for smoke control but may be made from composite material and are unable to withstand high temperatures. Sophisticated systems may be applied in buildings where control of the internal environment is important, schools and commercial buildings are a perfect example of this.
Where to purchase an actuator