Ultraflex Control Systems proposes a complete line of electric chain and linear actuators, that allows the choice of the more suitable actual for every kind of requirement.
The following technical details are a valid support to this choice that must be effected considering the following elements:
Window type.
For bottom hinged windows (hinges on the bottom side, inside opening) it is recommended the chain actuators installation: they do not take up space inside the room and are aesthetically discreet. Moreover, for these kind of installations, are not usually required special protection class for water or powder. The installation of linear actuators would need very long brackets (not available).
For top hinged windows (hinges on the top side, outside opening) it is recommended the installation of actuators with a special protection class and enough powerful to support with sufficient rigidity the maximum load, that occurs when the window is completely opened.
We suggest actuators like Master, Twin Master or Supermaster with double link chains and till 40 kg force. It is possible to install also linear or rack actuators, considering their encumbrance and aesthetic effect.
For roof windows (skylighfs,domes, etc.), see the installation instructions for fop hinged windows.
For horizontal pivoting windows , follow the installation instructions for top or bottom hinged windows.
For louvres or sun blades windows operating it is necessary to specify the control level stroke; it is usually suitable the 1 80 mm stroke of our rack actuator.
For normal turn window (casement windows, inside opening) It is recommended the installation of a chain actuator on the vertical side, considering the right installation way of the chain: it doesn't have to bend because of the gravity force. Note that it is impossible to obtain an 9C opening (see details about the actuator stroke).
Actuator stroke

The necessity of a wide window opening contrasts with the following factors:
a) for a chain actuator the stroke must not exceed 1 /3 of the window height, otherwise the chain bending would cause a loss of rigidity an for this reason a loss of performance in the long run.
b) for a linear actuator if is necessary to consider the actuator encumbrance inside the room; aesthetic effect apart, if grows as much as the required stroke increases, and if must be considered also the actuator rotation angle. In order to avoid interferences of the actuator with the elements in the room, if is necessary to evaluate carefully the position of the rotation axis opportunely choosing and positioning the fixing brackets. For this purpose, UCS proposes for all the linear actuators side fixing brackets, sliding within the proper dovetail slide on the actuator.
Actuator force
To calculate the window opening and closing force, please refer to the following simplified formula:
For vertical bottom or fop hinged windows: 41-1
Therefore, the required force is lower as higher is the window leaf and shorter is the required stroke.
For horizontal windows (roof windows, skylights,domes, etc.) 41-1
For inclined windows apply the formula for the horizontal windows;that is necessary if during the opening the window lie in horizontal position, and anyhow to take precautions in the other cases.
In the above mentioned formulas the wind load and snow load have not being considered. Regarding the wind load, it is necessarily to be considered above all for wide windows; if they are very high, for example, the greatest part of their weight is loaded on the hinges and the required opening force is very reduced, but In case of wind the effect on the large surface is considerable and the actuator must be choosed carefully.
Protection class
The chain actuators are less protected from water or solid bodies (dust, sand, etc. ) than the linear actuators. Some linear actuators, with protection class IP 65, are practically watertight in static conditions.
For this reason we suggest to install chain actuators on bottom hinged windows or, in connection with a rain sensor, on top hinged windows. An excellent compromise are our chain actuators Master and Twin Master (protection class IP 44), as their electronic component is closed inside a watertight plastic box.
Large windows
For very large windows only one pushing point in the central position cannot be sufficient. When the window is closed its corners can not be watertight or airtight and, anyway, when if is opened the stability is compromised in case of wind. We recommend to install two pushing points (or pulling points) If the window is larger than 1,5 m; also for an inferior width if the window leaf rigidity (profile + glass or polycarbonate) is not sufficient.
The installation of two actuators on the same window leaf is not possible, because it is not possible to guarantee the constancy in time of the actuators speed, with consequent probable break of one of them. In this case if the actuators are not equipped with the electronic stop system, it results the break of the second actuator or of the window.
The UCS range proposes exclusive solutions to solve this problem: Twin Master or Dual Rack actuators or two chain openers on the same window leaf controlled by a Multimec.
For any further information do not exhitate to contact our technical department.