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The method for best reducing light pollution, therefore, depends on exactly what the problem is in any given instance. Possible solutions include: Utilizing light sources of minimum intensity necessary to accomplish the light's purpose. Turning lights off using a timer or occupancy sensor or manually when not needed.
When sensors were placed on desktops in an office building, an penalty of 24% on energy saving occurred. [7] In both the open- and closed-loop configurations, the signal from the photosensor must be carefully calibrated to accurately indicate the effect of exterior daylight variations on the light level on 'important function' areas in the ...
The useful daylight illuminance calculation is based on three factors—the percentage of time a point is below, between, or above an illuminance value. The range for these factors is typically 100–2,000 lux. Useful daylight illuminance is similar to daylight autonomy but has the added benefit of addressing glare and thermal discomfort. [44]
A complete sensor consists of a motion detector, an electronic control unit, and a controllable switch/relay. The detector senses motion and determines whether there are occupants in the space. [9] It also has a timer that signals the electronic control unit after a set period of inactivity.
A twilight switch is an electronic component that allows the automatic activation of a lighting circuit when natural light drops in a given environment. Among a large number of uses, the most common is to enable automatic lighting of streets, roads, highways, roads, gardens, courtyards, etc., when sunlight drops below a certain level (e.g.: a ...
Occupancy sensors to allow operation for whenever someone is within the area being scanned can control lighting. When motion can no longer be detected, the lights shut off. Passive infrared sensors react to changes in heat, such as the pattern created by a moving person. The control must have an unobstructed view of the building area being scanned.
As PIR sensors are not perfectly reliable a timer is needed to avoid the lights flashing off and on as the occupier moves out of detector range. The timer interval is short though compared to a push-button timer; it times the interval between sightings of the occupier, not the time of occupancy. Such sensors are also used for restrooms.
Digital Addressable Lighting Interface (DALI) is a trademark for network-based products that control lighting.The underlying technology was established by a consortium of lighting equipment manufacturers as a successor for 1-10 V/ 0–10 V lighting control systems, and as an open standard alternative to several proprietary protocols.