Manual for ombra BST
LON slat angle automat
Order No.: 341 298
5. Device functions
With the device ombra BST the slat tracking and the shading correction can
be realized.
5.1. Slat tracking
Slat tracking cyclically adjusts the position of blinds to the current position of
the sun. This ensures that every room is optimally supplied with natural
daylight without allowing direct sunlight (CUTOFF control strategy). For the
frequency of the adjustments during the course of the day, in addition to the
different positions of the sun depending on the season and time of day, the
slat geometry and the positioning accuracy must be taken into account.
Glare shield strategy
Slat tracking guarantees the optimal use of daylight while taking into account
the necessary glare protection to create ergonomic working conditions. For
this purpose, a slat setting angle is calculated depending on the current
position of the sun, the alignment of the facade and the slat geometry of the
blinds used. This angle is sent to the relevant actuators and the slats are
positioned in such a way that direct sunlight does not shine into the room.
This type of tracking strategy is called cut-off or glare control strategy.
If the upper brightness limit is exceeded for longer than the parameterizable
switch-on delay, the slat tracking system positions the blind in the
parameterized extension length and cyclically determines the optimum slat
angle according to the cut-off strategy and sends the necessary movement
commands to the assigned sun protection actuators. If the brightness then
falls below the lower brightness limit for the duration of the switch-off delay,
the tracking is deactivated and instead a movement command is executed,
which moves the sun protection into a defined waiting position.
These delay times largely prevent an immediate reaction of the sun
protection system to short-term fluctuations in brightness and the resulting
interruption. The upper and lower limit values can be set in a range between
500 and 40,000 lux.
Light control strategy
Usually, blinds with non-mirrored slats are used. However, if you have deep
rooms and the daylight yield has a higher priority than the glare protection,
then mirrored slats can be used. The slat setting angle is then calculated with
additional consideration of the specific light directing angle of the mirrored
slats and the desired angle of incidence with which the light should be
directed into the room. This type of tracking is called light control. If you want
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08.09.2020
