Encyclopedia of Color Science and Technology

2016 Edition
| Editors: Ming Ronnier Luo

Lighting Controls

Reference work entry
DOI: https://doi.org/10.1007/978-1-4419-8071-7_134

Synonyms

Definition

Lighting controls are intelligent network-based lighting solutions. They incorporate the communication between various system inputs and outputs related to lighting control. Input can be given manually by humans and/or by sensor signals or parameter settings. Part of the control systems are unusually one or more local or central computing devices.

Basics

Lighting control is understood to mean the manual or automatic tuning of a lighting situation inside a building, fixed to a building or in an outdoor area. In its simplest form, the tuning is performed using a light switch or dimmer; in more complex configurations, sensors are used as well as control curves (time lines) and/or control inputs. As a basic requirement, the lighting installation must allow the light sources it incorporates to be varied individually, in groups or all together. As a minimum, this means the ability to alter the brightness of the light sources but can also include light color and/or spectral composition or even colors. The lighting installation incorporates not only the light fittings (luminaires), operator control units, and control devices, but also the blinds or other shading devices which regulate the amount of daylight entering the building. The emergency lighting system can also be integrated. In the case of building management systems, the lighting installation is linked up with other automated services such as heating, ventilation, and air-conditioning.

This type of integrated lighting control is often referred to as lighting management. The purpose of lighting management is to provide the right light in the right place at the right time [1, 2, 3].

Overview

The usefulness of lighting control is easy to understand as tuning the light for a particular purpose is not an invention of modern times. Human beings intuitively seek the ideal lighting situation. They spend their lives alternating between periods of activity and relaxation in keeping with the rhythm of day and night. Over the course of the day and the year, they seek and experience the change and variation of natural light.

The invention of electric light brought with it the advantage of having “brightness at the push of a switch,” available at all times. However, there was also an inherent technical limitation: the ability to tune the electric light was initially restricted to switching it on and off. Lighting was a static arrangement. Despite the fact that the incandescent lamp was dimmable from the outset, this feature proved difficult in the case of discharge lamps. The first widely used fluorescent lamps as well as high-intensity discharge lamps proved reluctant when it came to dimming. Both the physics of these lamps and the ballasts required to operate them made it difficult to regulate their light output without considerable effort. Merely switching them on and off therefore became the common practice. Switching different groups of luminaires was the only approach that came anywhere near “lighting control.”

In the meantime, the available technology has vastly improved. Today’s fluorescent lamps can be cost-effectively dimmed using electronic ballasts, and in the case of LED light sources, tuning the brightness was never a problem. High-intensity discharge lamps, on the other hand, continue to hold out against straightforward dimming.

Lighting control is attracting a lot of attention and is considered a necessary component of a lighting solution.

The main reasons for using lighting control are as follows:
  • To increase energy efficiency: Dimming and switching reduce the amount of energy consumed by the artificial lighting. When users want less or no light, the artificial lighting can be dimmed or switched off. And if sufficient daylight is available, this can partially or entirely replace the artificial lighting.

  • To improve the light quality: The ability to adjust the lighting environment to suit the activity or individual preference ensures optimum light quality. Light can be used to set the scene in interiors and in outdoor areas.

  • To enhance safety: Emergency lighting can be integrated.

  • To ensure flexibility: By readdressing the individual luminaires, it is possible to provide a fast and flexible response to changes in organization and work layouts. Individual lighting scenes (moods) can also be programmed and changed.

Applications

Where should lighting control be used? The emphasis will vary depending on the application:

Shops

Intuitive control points invite users to adapt the lighting scenes to suit the activity – ranging from light for working at the cash desk to attractive color changes in the lounge.

Growing awareness of the need to save energy has paved the way for dimmable luminaires in retail spaces. It is possible to enhance the visual impression of merchandise and architecture by coordinating changes in color temperature and luminance. High comfort, great flexibility, and low maintenance are the characteristic features of these controlled lighting solutions. The light spectrum, for instance, can be optimally adjusted to suit the illuminated object without the complication of having to change filters. Using control points, timelines, or daylight-linked management of the artificial lighting, the general illumination can also be gradually changed in line with expected light levels over the course of the day. The staging of merchandise to create strong emotional appeal and surprise effects is achieved with the appropriate static and dynamic lighting scenes. Making use of available daylight not only saves energy but also helps to make zones within an interior particularly attractive.

Façades

The use of LED technology in conjunction with lighting control systems has brought about a revolution in façade illumination. The subtlest of messages can be communicated using media façades. Dynamic façade design in particular is aimed at directing the gaze and conveying information. While ecological discussion focuses primarily on the amount of scattered light in the night sky, avoiding the unnecessary use of light by defining sensible operating hours would seem more important. The ultimate purpose of staging façades with light is to attract attention. It therefore makes sense for façades to be lit up exclusively in the evening and morning hours when greater numbers of people are circulating. This approach enables the identity of companies and communities to be highlighted, structures outdoor spaces at night, and assists nighttime perception while simultaneously addressing ecological objectives.

Museums

Lighting control ensures that sensitive exhibits are only exposed to light which is absolutely necessary, i.e., the level of luminance or the light color required for good perception or when visitors are present, e.g., using occupancy sensing. On and off times can be defined for specific hours of the day. Blinds control and daylight sensors ensure that exactly the right amount of daylight is admitted to achieve a balance between the needs of architecture, human well-being, preventing harm to exhibits, and saving energy. The emergency lighting is discreetly and safely integrated into the lighting management system which provides central monitoring and ensures reliable visibility in an emergency situation.

Hotels

In hotel rooms, intuitive control points which allow the guest to make selections according to individual preference are the first priority. The guest sets the lighting environment. With convenient control of the blinds, the levels of artificial light and daylight are adjusted to suit different activities and visual needs such as watching TV, putting on makeup, or reading. Dynamic lighting moods, with flexible definition based on timelines, or controlled according to weather situation or time of the day, significantly affect the well-being of the guests, particularly in hospitality or wellness areas. In entrance zones, lighting moods based on the outdoor light can also optimize visual adaptation for arriving guests, giving them security and orientation. Defined lighting scenes in conference areas support the use of different media and enable the appropriate light to be provided at the press of a button.

Health and Care

A homely atmosphere and care activities call for entirely different lighting scenes which are available at the press of a button. Intuitive operating features to suit the age and physical abilities of the occupants as well as the accessibility of the control units are the key to successful lighting solutions in hospitals and care homes. The amount of light required by the eye increases with age. For precise visual tasks, the artificial lighting can be individually adjusted by care staff and patients. In addition, the aging eye filters out blue light, affecting biological processes such as the internal clock and cycles of rest and repair. This must be compensated at specific times of the day by spending time outdoors or through biologically effective artificial light with high intensity and a high blue light component. The use of timelines in lighting management systems permits this interplay of artificial light and daylight at appropriate times of the day.

Office

Lighting control optimally addresses individual lighting needs depending on the age and visual task. Concentrated work and increasing communication call for entirely different requirements to be met by the lighting concept. Biologically effective artificial lighting components at the right time of day in addition to daylight help the internal clock and raise alertness. Lighting management systems with a high level of automation can achieve maximum energy savings as well as flexibility in the case of office moves, thanks to time management, daylight-linked control, and occupancy sensing. Employees readily accept the technology when it gives them the freedom to alter their lighting environment. This means providing adequate means of control and small groups of luminaires with assigned access.

Industry

Industry offers particularly high potential for saving energy. Long periods of lighting use due to shift and night work as well as a lack of daylight in many work areas and rooms mean that investments in lighting management have short payback times. Lighting management ensures the required flexibility in production areas. New lighting installations have to be overdimensioned in order to take into account the effects of deterioration of the installation over time. This additional energy consumption can be counteracted with daylight-linked or constant light control which continuously adjusts lamp output in line with the available daylight or length of service. Integrated lighting solutions allow the interaction between different services. Maintenance and monitoring operations are also optimized through the incorporation of emergency lighting. Interfaces to other services ensure the convenient and cost-effective operation of buildings.

Education

New forms of teaching and new media technologies call for flexible room use and frequent adaptation of the lighting situation. Intuitive control units are used to select defined lighting scenes at the press of a button, i.e., for working in small groups or traditional teaching, reduced lighting levels for presentations using LCD projectors, or higher vertical illuminance for blackboards and flip charts. Comfortable control units enable the user to rapidly adapt the lighting situation.

Daylight activates human beings and enhances their feeling of well-being as well as their performance. With daylight-linked control of the artificial lighting or occupancy sensing, it is possible to achieve maximum energy savings without restricting the quality of light. Blinds control not only improves the contrasts of presentation media but also increases room comfort because glare and heat gain can be minimized. Conveniently placed control units near the door and on the teacher’s desk enable intuitive selection of the appropriate lighting situation.

Corridors and Stairways

Circulation zones are predestined for lighting management. Ideally, the lighting should only be activated if a person approaches. The light should be on once the person has entered the circulation zone. Movement detectors must be suitably positioned. The energy consumption of lighting in corridors and stairways can be further reduced in conjunction with daylight-linked control.

Streets and Public Spaces

Illumination is necessary for reasons of safety and orientation in streets and public spaces. Switching the lighting on and off in conjunction with the available daylight has long been a common practice. Nowadays, it is also possible to reduce brightness levels at hours of the night when traffic density decreases. Control is performed centrally for streets, districts, and public spaces.

Movement detectors can be installed to ensure that the brightness of the lighting anticipates the approach of pedestrians and cyclists. While the general brightness level is lowered, it can be increased at the point of use to ensure safe circulation.

Domestic

Being able to vary the lighting takes on particular emotional importance in the home setting. Well-being and work, social interaction, and intimacy all take place within the confines of a small space. Access to different lighting moods at the press of a button enables the occupants to set the scene for their private space with area, accent, and mood lighting. Blinds are frequently integrated into the control system to regulate solar heat gain. Time control is also a security feature which can be used to make the house appear occupied when the residents are away on holiday.

Individual lighting scenes can be selected from a central control panel. Switches incorporating a reduced number of scenes on doors and in readily accessible locations allow intuitive operation of the lighting installation.

The possibilities and the requirements of the application are taken into account in the lighting concept. The lighting designer incorporates the operator control units, the control devices, and the choice, number, and arrangement of luminaires, blinds, and other actuators.

Interfaces for Lighting Management

Generally, there are interfaces between the user, the environment, and the lighting installation.

The user can actively intervene using different operator control units:
  • Standard or momentary action switch, with or without dimming function: The simplest form is a switch and/or dimmer frequently fitted near the door or in another readily accessible location in the room.

  • Multifunction switch: Also near the door or in a readily accessible location, for calling up different lighting scenes.

  • Remote control: This can be an IR or wireless unit or the user’s mobile phone, for calling up individual lighting scenes.

  • Workstation control: In this case, operation is through the user’s own computer or using a control unit directly at the workstation.

  • Central control unit: At a defined location, trained personnel can select specific scenes or timelines for the lighting installation, often using a touch screen.

The environment can be integrated by means of sensors or defined timelines:
  • Daylight sensors: Sensors installed outdoors or near daylight openings detect the level of daylight brightness and transmit the appropriate signals to control or regulate the lighting installation (luminaires and blinds).

  • Presence or absence detectors: These sense whether there is a person within their detection zone. The signals they transmit switch the lighting installation on or off.

  • Time signals: The lighting can be switched to preselected scenes at set times. The simplest case is to switch off all the lights at specific times. It is also possible to call up timelines to automatically tune the lighting in accordance with programmed strategies.

  • User behavior sensors: Signals based not only on presence or absence but also on user movement patterns can be used to initiate situation-based tuning of the lighting situation.

  • Environmental signals: Other predefined data can be used for control purposes, e.g., to maintain constant luminous flux on the basis of set maintenance factor curves or to reduce installation output if the energy demand exceeds a specific limit.

Behind each operator function, there are signals which are processed by the lighting management system. This means, for instance, that if a sensor detects that a person has left the room, switch off can be delayed.

Intelligent control is based on the following logic: for each activity, a lighting scene is defined, saved, called up, and modified as required. Each scene is assigned a name and a symbol which are shown on the operator control units. The lighting scenes are activated automatically by means of presence detectors or simple time inputs. The basic philosophy is always the same: it must be possible to manually override any activated lighting scene.

Strategies for Lighting Management

What strategies can be used to achieve useful objectives with a lighting management system? Firstly, those objectives have to be defined and secondly, acceptance of the usefulness of the objectives put to the test.

One objective is to increase energy efficiency:
  1. 1.

    Individual switch on and off: This simplest objective is dependent on a switch being located near the user. Users appreciate this possibility but frequently do not use it.

     
  2. 2.

    Daylight-linked control – switching function: Automatic switch on and off; the control input is the daylight measured by a sensor.

     
  3. 3.

    Daylight-linked control – switching function: Automatic switch off and manual/individual switch on; this requires a daylight sensor and a switch.

     
  4. 4.

    Daylight-linked control – dimming: Automatic setting at a constant value; the control input is the daylight measured by a sensor.

     
  5. 5.

    Daylight-linked control – dimming: Automatic switch off and individual switch on; this requires a daylight sensor and a switch.

     
  6. 6.

    Occupancy-based control – switching function: Automatic switch on and off; the control input is delivered by a sensor which detects human presence.

     
  7. 7.

    Occupancy-based control – switching function: Automatic switch off and individual switch on; this requires a presence detector and a switch.

     
  8. 8.

    Constant light control (without daylight): A constant level of luminous flux is maintained to compensate for the decrease in light output with increasing age of the installation; the control input is delivered by a programmed timeline or a sensor for the emitted luminous flux.

     
  9. 9.

    Time-based control: Programmed lighting scenes are called up, and the installation is switched on or off at set times.

     
  10. 10.

    Load shedding: Automatic limitation of energy demand.

     
Another objective is to improve the quality of light:
  1. 11.

    Activity-related control: Individual setting of a lighting scene to suit an activity; this includes the switching and dimming of individual blinds, luminaires, and groups of luminaires in the adjacent area.

     
  2. 12.

    Individual daylight control: Individual operation of blinds to avoid disturbances such as glare and heat.

     
  3. 13.

    Automatic daylight control: Automatic control of blinds to reduce heat gain and glare from direct sunlight and excessive outdoor brightness; this requires a daylight sensor.

     
  4. 14.

    Algorithmic lighting: Automatic sequence of variations in the lighting based on programmed rules.

     
  5. 15.

    Room-related scene setting: Selection of preset static or dynamic lighting scenes.

     

User Acceptance and Energy Efficiency

While the various strategies might bring great benefits from a planning perspective, they also have to be accepted by the users. Many field studies have looked at the question of user acceptance.

One of the essential requirements is the ability to manually override each activated lighting scene. In comparison with automated processes, however, this makes it difficult to calculate the parameters for possible energy savings, the determination of which is a major challenge in view of the many unknown factors.

The behavior of energy-conscious occupants receives too little attention in calculations of this kind. Making the groups of luminaires as small as possible provides greater opportunity to change the lighting situation manually and individually to suit requirements. Large rooms with several groups of luminaires do not lend themselves to this approach as it is difficult for large numbers of users to agree the preferred setting of the lighting installation. For this reason, a smaller group of luminaires and operator control units must be installed in close proximity to enable the user to make spontaneous changes.

Changing weather conditions and unforeseeable user behavior make it difficult to predict energy usage. The time delay for presence detectors also plays a role.

In view of their complexity, the dynamic changes taking place in the world of work and in building use are continually being analyzed and measured in field studies carried out by different industries. In the context of a lighting management system, human behavior will always be more difficult to predict than technically defined parameters (Table 1).
Lighting Controls, Table 1

The table shows the effect of individual strategies on energy efficiency and light quality and assesses the associated user acceptance

Strategy

Operation

Energy efficiency

Light quality

Acceptance

1

Individual

 

Low

High

High

2

Daylight-linked control – switching

Auto off, auto on

Medium

Medium

Low

3

Daylight-linked control – switching

Auto off, manual on

High

Medium

Medium

4

Daylight-linked control – dimming

Auto off, auto on

High

Medium

Medium

5

Daylight-linked control – dimming

Auto off, manual on

Very high

Medium

High

6

Occupancy-based control – switching

Auto off, auto on

High

Medium

Medium

7

Occupancy-based control – switching

Auto off, manual on

Very high

Medium

High

8

Constant light

Auto

High

Medium

Medium

9

Time-based control

Auto

Very high

Medium

High

10

Load shedding

Auto

High

Medium

Medium

11

Activity-related control

Manual

Medium

Very high

Very high

12

Individual daylight control

Manual

Medium

High

Very high

13

Automatic daylight control

Auto

High

High

High

14

Dynamic lighting

Auto

High

Very high

Very high

15

Scene setting

Manual

Medium

Very high

Very high

Auto automatic

Technical Requirements

The transmission of information from the operator control units and control devices to the actuators is at the heart of any lighting management system. Actuators are luminaires, blinds, or other equipment integrated into the lighting management system.

Information transmission means the sending and receiving of signals, which can be achieved using various means:
  • The signal “on/off/dim” is sent via the power line.

  • Signal transmission between operator control units and control devices takes place using the power line.

  • Signal transmission between operator control units and control devices and to the powered luminaire/actuator uses a separate control line with standardized control signals (DALI, DMX)

  • Operator control units and control devices (e.g., computers) are networked via data lines. Communication is by means of bus (LON, KNX, Luxmate, etc.) or TCP/IP protocols.

Definitions

Bus protocols such as LON, KNX, and Luxmate: Bus systems network all technical services in the building and provide central control for heating, ventilation, window blinds, and security systems.

TCP/IP: Transmission Control Protocol/Internet Protocol (TCP/IP) is the set of communication protocols used for the Internet and is consequently also referred to as the Internet protocol suite.

DALI stands for Digital Addressable Lighting Interface and is a standardized digital interface for control gear and electronic ballasts. DALI can be used with a small number of lines to address large numbers of control circuits over large distances.

DMX is an acronym for Digital Multiplex, a standard for digital communication networks commonly used to control stage and event lighting. Nowadays, the DMX protocol is also frequently used by architects and lighting designers as it enables over 500 channels to be controlled individually with rapid signal sequences from a single central control unit.

Luminaires, blinds, and other actuators integrated into the lighting management system have to be compatible with the existing communication protocols and understand the signals. The actuators are assigned individual or group addresses so that they can be uniquely indentified within the network and to enable them to communicate.

In the case of classic lighting installations equipped with fluorescent lamps, dimmable ballasts have to be used. High-intensity discharge lamps, on the other hand, can rarely be dimmed, at best switched in stages. As a rule, LED lighting incorporates dimming. With relatively simple means, it also offers the opportunity to vary the light color (with a range from 2,700 to over 8,000 K) or even to set different colors using RGB diodes.

Lighting Design

The decision regarding a lighting management system should be made at an early stage of the project. Lighting management is an integral part of the overall building management system. For this reason, the lighting management system will often come under a different budget to the actual lighting installation itself.

The choice and layout of the luminaires should allow different lighting scenes to be selected.

The location of operator control units, the layout of the luminaires, and in particular the integration of daylight should be part of a holistic design approach. Service and long-term support for the lighting management system will ensure that the operators obtain the expected benefits.

Factors Driving Lighting Management

The growing demands for lighting installations to be energy efficient are currently a strong driver for the use of lighting management. European green building directives are leading to national regulations for energy requirements in buildings, which cannot be met without the use of lighting management. Daylight-linked control and presence detectors are therefore a necessity.

Green building certification schemes also look to reduce environmental impact with the aid of intelligent lighting management. Well-known schemes include LEED, BREEAM, DGNB, and CASBEE, among others. As well as helping to reduce energy consumption, the integration of lighting management can improve the quality of light for the users.

Cross-References

References

  1. 1.
    Craig, D.L.: Lighting Controls Handbook. The Fairmount Press, Lilburn (2007)Google Scholar
  2. 2.
    Simpson, R.S.: Lighting Control. Focal Press, Oxford (2003)Google Scholar
  3. 3.
    David, D.L., Houser, K.W., Mistrich, R.G., Steffy, G.R.: The Lighting Handbook, 10th edn. IES, New York (2011)Google Scholar

Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Zumtobel LightingDornbirnAustria