There are two main types of electric actuators that are available
to control opening vents. These are Linear actuators
and Chain actuators.
Linear Actuators
These devices incorporate a rigid rod that is driven by the motor to open
and close. The depth of a linear actuator will be at least 200mm greater
than the opening stroke therefore to open a vent to a typical distance of
300mm will require an actuator that extends at least 500mm into the
building space. Although these types of actuator are considered more
robust than Chain actuators for roof glazing applications, aesthetics will
generally require a less obtrusive device for this purpose.
Chain Actuators
These clever devices do not have a rigid rod. Instead a stainless steel
chain (similar to a bicycle chain) is housed inside the unit. When the motor
is engaged the chain is unwound and as it leaves the unit it becomes
semi-rigid and is able to push the vent open. Due to its compact and
unobtrusive design the chain actuator is considered the most appropriate
choice for our roof opening vents.
Chain actuators of the ACK4 series remain our first choice for most of our
contracts based on pleasing aesthetics and an impressive proven history
of this device. They are available in 230 volt models for general use and
also in 24 volt for integration with battery back-up control panels.
The electronic chain position control allows for seven opening lengths
ranging from 100m to 400mm and is capable of lifting weights of up to 30
kgs.
The actuator casing is die-cast and polyester powder coated in standard
colours of white and black. They can also be supplied in any RAL colour
for an extra cost. The electric parts are built with double insulation
(therefore earth wire is not necessary) and contained in a body of plastic
material to ensure a high protection level with an impressive IP55 rating.
Control Switches and Panels
All actuators can be simply controlled by a standard wall mounted on/off
switch. Alternatively an increasingly popular more advanced system is
available which incorporates a control panel with separate thermostatic
control and rain sensor device. These can be programmed to open or
close at defined temperatures and include a manual override and are also
available with a remote-controlled key fob which will operate the vents by
radio signal.
A typical control panel or standard switch will allow up to twelve opening
vents to operate simultaneously. On contracts where there are a very
large number of openers we would suggest using a commercial control
panel. Such a device would be capable of opening many vents, either
simultaneously or divided into zones. Other possible options are to have
timer controls for public buildings, wind sensors for exposed buildings and
even humidity and light sensors. Some control panels are also suitable
for connection to a BMS (Building Management System).
The wiring of the system is always excluded from our package, as this
should always be carried out by a qualified Electrician. We are able to offer commissioning on some of the more complex commercial control systems. |