OccuSwitch DALI
User Guide
Page 15
Movement sensor
The movement sensor is a PIR (Passive Infra-Red) sensor
that detects occupancy in an area . When installed in a
typical office ceiling at 3-metre height (between 2 .5 and 4
meter), it is sensitive for small movements within a range
of 4 by 5 meters and to large movements within a range of
8 by 6 meters .
The PIR sensor reacts on movement by means of
moving temperature difference such as the human body
temperature versus its surrounding temperature . It is
recommended to keep hot or cold moving air (like coming
from a heater, air-conditioner or other heat or cold air
producing equipment) away from the OSD’s to prevent
unwanted triggering of the system .
The movement detection range can be extended with an
extension movement sensor, which has the same viewing
specifications as the standard sensor .
D
Note
It is possible to limit the detection area of the
movement sensor with a retractable shield .
2 .3 .2
Daylight Dependent Regulation
The OccuSwitch DALI has an automatic Daylight
Dependent Regulation (DDR) with a dynamic offset for the
window and corridor rows . Daylight Dependent Regulation
helps to keep a constant light level at all situations .
Daylight sensor
The daylight sensor reads the actual average luminance .
The intensity of the luminance depends on the amount
of artificial and / or natural light in the room as well as
on how well this light is reflected towards the ceiling . The
light reflection depends highly on the colors and materials
chosen to furnish the office .
For more information on this sensor, see section “Light
sensing” on page 22 .
For calibrating the daylight sensor, see section 4 .2 .4 .
Dynamic offset control for window / corridor
Since the window area receives more daylight than
the corridor area, window and corridor luminaires are
controlled separately . Depending on the amount of
daylight entering the room, the output of both window and
corridor luminaire rows are dimmed to a minimum level
with a difference of up to 30% between the window and
corridor side .
When both window and corridor rows have been dimmed
to the minimum level for more than 15 minutes, the
window row will be turned off to ensure maximum energy
saving . The corridor side, however, will by default only dim
to the minimum level, hence indicating to the user that the
lighting is operational .
D
Note
This default can be overridden, in order to turn the
corridor row off as well . For this special case, please
contact your local Philips representative for details .
In the daylight override function, the lights will switch
on when someone enters the room even when there is
sufficient natural daylight available .
Figure 5 shows the dynamic behavior (offset) of the
window and corridor row luminaires .
Figure 5: Dynamic offset between window and corridor
80%
100%
30%
1%
max. offset
