FEATURE FOCUS: CLASSROOM DESIGN
use. Here, the school can select the ratio between 1:1 to 1:5 according to the lighting conditions in the room. In rooms with light floors and light furniture, the ratio between ceiling and work surface is 1:1, in rooms with dark floors and dark furniture 1:5. If required, this automatic control can be overridden. Teachers and staff can dim the light via the
pushbutton if they need more or less brightness. Alternatively, they can also intervene in the DALI- SYS control system via a PC. By means of a username and password, school
staff can be given access to areas in which they can influence the lighting control. They can log in via their browser and control the light in their room or office. Via a user-friendly interface, they can select scenes, switch and dims the light as appropriate. In a drama hall or sports hall, staff can also
control the light via smartphone. These scenes are stored in the system for different meeting situations, which can be called up with a click. For this purpose, the luminaires in the room are
authorisations. This ensures that school staff can access precisely the most relevant part of the system for their needs. For example, in a classroom scenario, as they
do at home, teachers and staff can activate the lighting via a light switch upon entering their room. The multi sensor then takes over intelligent control of the lighting in the room. Thanks to the passive infrared sensor (PIR], movement in the room is then detected, and depending on the programming, the light is automatically switched on and off. In addition to the PIR sensors detecting motion,
the multi sensors feature brightness detectors through which a daylight-dependent control of the lighting can be achieved. Furthermore, having measured this the multi-sensor only adds or dims as much artificial light as is necessary to reach the pre-set lux value in the classroom. To achieve the optimal function of the
intelligent system in place, the measured brightness value needs to be extremely accurate. This is achieved by finding the best location on the ceiling for the installation, where measurement is influenced by as little as possible by external factors such as reflection, direct sunlight, or other light sources. Brightness values must always be measured in the darkest part of the room, which may differ from classroom to classroom depending on its location in the school building. However, the detection range of the unit must of course ensure adequate cover of the students’ range of mobility in the room. For optimal lighting control, the difference
between the brightness at the desk and the brightness at the ceiling must be balanced in the logic of the multi-sensor. Therefore, the actual value measured by the light sensor on the ceiling is not used for the control in order to supplement the natural light with the appropriate amount of artificial light. Instead, a so-called reflection factor is used as the ratio of light between the work surface and the ceiling. With DALI-SYS, the weighting of the reflection
value is set individually according to the environmental variables of the respective place of
February 2022
www.education-today.co.uk 33
divided into groups and assigned dimming values. School staff can then switch from the ‘meeting’ scene with full illumination of the conference table to the ‘presentation’ scene with dimmed light in the area of the projection screen. A special function of DALI-SYS is called ‘guided
light’, which is also known on the market as ‘swarm intelligence’. With this function, luminaire groups are synchronised across DALI lines. Thus, when movement is detected, not only the luminaire group in which the movement is detected switches on the light. The adjacent luminaire groups also react, but with dimmed light. Therefore, the user is surrounded by a ‘cloud of
light’ which dims towards the outside. The user can therefore see what is happening in the adjacent areas at all times - they never look from a brightly lit area into a pitch-black area. The function is ideal for use in school staircases, corridors or open plan classrooms. Thanks to dimming, the use of the guided light function is more cost-effective than the usual complete 100 per cent lighting. The connection of DALI-SYS to a higher-level
building management system or to parallel existing systems for other trades such as heating,
ventilation, blind control or access control can be easily realised via the DALI-SYS BACnet router. Up to 712 so-called nodes are provided per router via BACnet/IP, with the help of which lighting values, presence and status information can be read out. Multi-state objects allow different lighting control commands to be routed to the DALI-SYS system from a higher-level software. In this way, the lighting control system can be
overridden from a BACnet-based control centre, for example. Maintenance can be facilitated by a quick system overview and automatic error notifications. Key figures such as the lighting duration of individual lamps or the energy consumption of the system can be viewed transparently at any time. Schools can monitor, configure, and maintain the systems via PC or mobile devices. This is how user-friendly and environmentally friendly lighting controls can be set up today in schools with networked systems which benefit everyone.
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48
