Lighting MAnAgEMEnt SYStEM - OMS lighting

Types of control
Manual
Automatic
Combined
Constant illuminance sensor
Daylight simulation
PIR sensors can be utilised in both indoor
and outdoor applications, be installed at
various heights and work at different
levels of sensitivity. the area that can be
scanned depends on the height of installation
and set sensitivity.
The sensitivity of the sensor depends on
various things. The ambient temperature of
the space compared to the temperature of
the person moving within the space, the direction
of scanning and the extent to which
the sensor is able to scan the movement.
Maximum sensitivity in terms of movement
detection is when the person passes
through the ‘sight’ of the sensor at a right
angle. When movement is parallel to the
sight of the sensor sensitivity is decreased.
In spaces where the scanning area is
limited by various objects it is possible to
use high-frequency movement sensors.
High-frequency sensors are able to detect
movement even through glass and thin
walls, even the slightest movement, all
independently of any changes in temperature.
In order to achieve maximum coverage
it is useful to overlap the scanning areas of
individual sensors.
For an ideal coverage of the space it is
in general suitable for the scanning areas
of the individual movement sensors to partially
overlap each other.
scanned angle
sensor
Depiction of the detection area
non-scanned
area
radius of the
scanned area
scanned
area
height of sensor location
sensor A
minimal distance = X+Y
X
sensor B
minimal
vertical
scanning
area
Y
height of sensor location
Suitable location of the movement sensors with
partially overlapped scanning areas
scanned
area
100%
lighting
intensity
10%
movement
0% time
Time progress of the movement sensor—without delay
100%
lighting
intensity
10%
0% time
Time progress of the movement sensor—with delay
100%
lighting
intensity
movement
movement
delay time
0% time
Time progress of the movement sensor—with double delay
100%
lighting
intensity
Incremental gradual
increase (t=0s)
Smooth gradual
increase (t>0s)
delay time
delay time
Incremental gradual
decrease (t=0s)
0% time
100%
lighting
intensity
movement
movement
Smooth gradual
decrease (t>0s)
When we use motion detection based
lighting control it is often apt to incorporate
a delay in the dimming of the
luminaires after the person has left the
space. this means that the luminaires
remain on for a defined time after presence
is no longer detected.
How long this delay will be depends very
much of the type of space and the assumed
frequency of movement or occupancy. The
dimming can be set at a certain level, for
example 10 % of the luminous flux, or even
0 % where this is appropriate. A reduced
luminous flux level approximately 10 % is
used as a safety measure so that the space
is not entirely dark, or that security cameras
may still effectively operate, and also
to prolong the lifespan of the light source.
This functionality is often referred to as ‘the
corridor function’. The system can also be
set so that the lighting is reduced to 0 %
after a subsequent delay.
Once motion is again detected the luminaires
switch on. The lighting level can
be increased or decreased immediately or
gradually, either smoothly or incrementally.
The advantage of this graded change, possibly
taking two seconds, is that the human
eye is not strained by a sudden change in
visual conditions, and also the light source
lifespan is not shortened by extreme changes.
This type of solution is ideally suited to
spaces with a high frequency of occupancy
and movement, for example in warehouses
and corridors.
0% time
Scanning area of the passive infrared sensor (PIR)
Scanning area of the high-frequency movement
sensor
Time progress of the movement sensor—with smooth regulation of luminous flux
36 I TYPes of control
TYPes of control I 37