Types Of Lighting Controls

Lighting Controls


At the nerve center of a lighting system are the controls,which manipulate the level of illumination in each space and provide flexibility in those spaces used for variety of functions.
Controls are the only part of the lighting system that the user is able to touch so should be easily adjustable.Lighting controls can aid in managing and limiting the energy consumption in a space, while still providing the individual user flexible light levels in multiple use spaces.



There are five basic strategies to save energy, enhance performance and offer convenient  light level changes, they are

  • Occupancy sensing
  • Scheduling
  • Daylight Dimming
  • Tuning
  • Preset dimming
Occupancy sensing and scheduling are means of limiting the hours of lighting to the hours of occupancy. Daylight dimming aims to dim electrical light as available daylight enters a space to achieve a constant light level.Tuning and preset dimming allow the user to change light levels for specific tasks or events.

Occupancy Sensors

Simply turning lights off when a space is vacant can save tremendous amounts of electricity. Estimates of savings range from 30% to 70% in rooms with intermittent use. Private offices, conference rooms,smaller shared spaces, restrooms and storage areas favor the use of occupancy sensors, which automatically turn the lights off a few minutes after the space becomes vacant. In a private office , a switch mounted sensor works well and gives the user easy control of the Lighting.
In larger shared office areas ceiling sensors may be zoned to cover a group of people who normally work together. These sensors may be manually activated for maximum energy savings,or may be set to automatically turn on when motion is detected.

Scheduling

In a large shared office space, circulation areas and lobbies, turning lighting circuits on and off on a timed schedule is an efficient strategy for energy conservation . Typically , low voltage switching systems or controllable circuit breakers are combined with a time clock or Building management system to turn lighting on and off at times that accommodate the average occupancy of a building. Individual   workers who arrive early , or stay late normally activate their personal zone of light by sending a code to the controlling system via phone or networked computer.

Daylight Dimming

These energy saving strategies employ photo-cell combined with a controller and fluorescent dimming ballasts to take advantage of available daylight entering a space to reduce the electrical lighting requirements.The space must be carefully designed to allow daylight to enter at a specific useful angles ,and the building must be sighted appropriately to make daylight dimming econimically feasible. Photocell placement is critical as well, and needs to be able to monitor useful light striking the work surface. Daylight dimming can work well in circulation and public spaces where some systems are available that allows for aesthetic balancing of ambient and accent lighting in response to daylight.

Tuning

Tuning is a strategy that simply gives the individual a manual dimmer to adjust the light settings below the design criteria.This may be accomplished in conjunction with any of the other strategies such as occupancy sensing and scheduling. This strategy works well in private office,or small shared spaces where all occupants are performing similar visual tasks and have similar visual abilities. It works less well in large shared office spaces where the light output of all fixtures is required to provide average luminance throughout the space.


There are two approaches the equipment regulations which set the minimum efficiency for specific components and the application standards which limits the available power for lighting .Both approaches address lighting power and have been enacted in various building codes of North America. 

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