Lighting Systems

What we're covering:

• electric lighting principles
• definitions of lighting terms
• types of lighting

Electrical Lighting Principles

Light is electromagnetic radiation (EMR) within a certain portion of the electromagnetic spectrum. The word usually refers to visible light, which is visible to the human eye and is responsible for the sense of sight. Visible light covers the wavelength range from approximately 380 nm (nanometres) to 760 nm, or 3.8 × 10−7 to 7.6 × 10−7 m, between the infrared (with longer wavelengths) and the ultraviolet (with shorter wavelengths). The eye discriminates between different wavelengths in this range by the sensation of colour. Blue and violet correspond to the short wavelengths, red to the long, and yellow and green to the middle of the visible range of wavelengths.

In physics, the term light sometimes refers to electromagnetic radiation of any wavelength, whether visible or not. In this sense, gamma rays, X-rays, microwaves and radio waves are also light. However, for our purposes, the term light applies only to visible radiation.

Definitions of Lighting Terms

• Luminous flux: This refers to the total amount of visible light emitted by a light source in all directions. It is measured in lumens (lm) and indicates the brightness of a light source. The higher the number of lumens, the brighter the light source.
• Luminous intensity: This refers to the amount of light emitted by a light source in a particular direction. It is measured in candelas (cd). One candela is equivalent to one lumen per steradian (lm/sr), where the steradian is a unit of solid angle. To measure luminous intensity, a device called a photometer is used. A photometer consists of a light sensor (usually a photodiode or photomultiplier tube) that is sensitive to visible light, and a display or recording device that displays or records the measured luminous intensity.
• Illuminance: This refers to the amount of light that falls on a surface per unit area. This is one of the most commonly used measurements of light and indicates the brightness of the illuminated surface. It has the symbol E and is measured in lux (lx), where 1 lux = 1 lm/m2. Illuminance depends on both the luminous flux of the light source and the distance between the source and the illuminated surface. Natural illumination is daylight from the sun as the source while artificial illumination comes from an artificial light source.
• Luminance: This refers to the amount of light that reaches our eyes from a surface. Luminance is different from illuminance in that it measures the light emitted or reflected by the surface, not the light falling on the surface. Luminance is measured in candelas per square meter (cd/m²) and indicates the brightness of the surface. If we have two light sources per unit of apparent surface area with the same luminous intensity and one of them has a smaller surface area, it will appear brighter. Luminance is measured using a lux meter is used, which converts the light signal into an electrical signal that is later amplified and allows the reading of intensity on a calibrated lux scale. It is important that before measuring, the device is calibrated and marked 0.
• Glare: Glare is excessive contrast of brightness or colour in the visual field. Excessive luminance of an object in relation to its background is a common source of glare. Potential glare in lighting installations can be minimised by using indirect lighting sources, fixtures with baffles or louvres, lighting controls such as dimming etc.
• Colour Temperature: The colour temperature of a light source refers to its perceived warmth or coolness. Light sources with a lower colour temperature (around 2700-3000K) appear warm and yellowish, while those with a higher colour temperature (5000-6500K) appear cool and bluish. Understanding colour temperature is crucial when selecting lighting for different environments, such as warm colours for residential spaces and cooler colours for commercial settings.

Activity

1. Match the following terms to their correct definitions.

2. Answer the questions in the worksheet to test your understanding of the lighting terms.

Types of Lighting

A good lighting setup combines different types of lighting to create a welcoming space where you can easily work or relax. The three basic types of lighting are ambient lighting, task lighting, and accent lighting. Each type of lighting has a particular function and is used to achieve different effects in a space.

Ambient Lighting

Also called general lighting, ambient light provides the main source of light for a room. It provides a uniform level of illumination throughout the space, ensuring safe and easy traffic. It is not ideal for working closely with things or highlighting things around your space.

Ambient lighting can be achieved through a variety of light fixtures, such as ceiling-mounted fixtures, recessed lighting, or wall sconces. The function of ambient lighting is to provide a comfortable level of illumination that allows people to move around the space, performing basic tasks and socialising.

Task Lighting

Task lighting or ‘office lighting’, is focused on a specific area where a task is being performed, such as reading, cooking, or working. It provides focused illumination that is bright enough to make the task easier to perform, without having to increase the ambient light level of the room.

Task lighting can be achieved through a variety of light fixtures, such as desk lamps, under-cabinet lighting, or pendant lights.

Accent Lighting

Accent lighting is used to highlight or accentuate a particular feature or object in a space, such as artwork, sculptures, or architectural details. Accent lighting creates visual interest and adds depth and texture to a space.

Effective accent lighting requires the installation of three times more light on the focal point than ambient lighting generally provides. Accent lighting can be achieved through a variety of light fixtures, such as spotlights, track lighting, directional recessed fixture or downlight, wall sconce fixtures.

In summary, ambient lighting provides general illumination to a space, task lighting focuses on specific areas where tasks are being performed, and accent lighting highlights particular features or objects in a space. By combining these three types of lighting, designers can create a well-lit and visually interesting space that is both functional and aesthetically pleasing.

You must be clear about the purpose of a room before planning the lighting. A good lighting plan maximises the use of all three lighting types to illuminate a room depending on function and style. Start with ambient lighting, then identify areas where there will be a need for task and accent lighting.

What we're covering:

• luminaires
• lighting systems

Basic lighting systems consist of a light source, a control device, and a power source. The light source can be incandescent, fluorescent, LED, or halogen, depending on the application and the desired lighting effect. The control device can be a switch, a dimmer, a timer, or a sensor, depending on the level of control and automation required. The power source can be mains power or a battery, depending on the location and the backup requirement.

Luminaires

A luminaire is a complete lighting unit that includes the light source(s) as well as the housing, mounting, and wiring necessary to install and operate the light source(s) safely and effectively. The term "luminaire" is often used interchangeably with "light fixture." 

The Wiring Rules, define a luminaire as:

"an electrical device which is intended to distribute, filter, or transform the light emitted from one or more lamps and which includes all components necessary for fixing and protecting the lamps, as well as any means of connection to the electrical supply." 

Lighting system

There are several lighting systems used for various applications in residential and commercial settings, including incandescent, fluorescent, LED, and halogen lighting. Each type has its own unique properties and applications, so it's important to understand the differences between them. 

Incandescent Lighting

This type of lighting system has been widely used for many years however it is becoming less common due to advances in technology. It is often used in residential settings, such as living rooms and bedrooms, and can be used as accent lighting in retail settings.

Incandescent lighting works by passing an electric current through a wire filament, which heats up and produces light. The filament is typically made of tungsten, a metal that has a high melting point and can withstand the high temperatures required for incandescent lighting. As the filament heats up, it emits light in all directions, creating a warm and glowing effect. 

Incandescent luminaires are available in various shapes and sizes, including bulbs, candles, and reflectors.

1. Glass bulb
2. Low pressure inert gas (argon, neon, nitrate)
3. Tungsten filament
4. Support wires
5. Contact wire (goes out of stem)
6. Contact wire (goes into stem)
7. Stem (glass mount)
8. Cap (sleeve)
9. Insulation (vitrite)
10. Electrical contact

Features of incandescent lighting include:

• Warm yellowish colour temperature of around 2700K, creating a cozy and inviting atmosphere in residential settings.
• High colour rendering index (CRI): The CRI measures the ability of a light source to accurately show the true colours of objects. Incandescent lighting has a high CRI, meaning that it provides excellent colour accuracy and makes colours appear more vibrant and natural.
• Dimmable which allows for flexible control of lighting levels and can help to create a more comfortable and relaxed environment.
• Short lifespan typically last around 1,000 hours, which is significantly shorter than many other types of lighting.
• Low energy efficiency converting about 5% of the energy it uses into light. Rest is lost as heat, leading to increased cooling costs in warmer climates.
• Environmental concerns as it contains small amounts of toxic materials such as lead and mercury. Its low energy efficiency makes it a less environmentally friendly option compared to other lighting technologies.

Incandescent lighting is being phased out in many countries in favour of more energy-efficient lighting technologies such as LED. They are mostly used for decorative and accent lighting in residential settings and specialty lighting applications such as theatre and stage lighting.

LED Lighting

LED luminaires are increasingly popular in NZ due to their energy efficiency and longevity. They are suitable for a wide range of applications, including indoor and outdoor lighting, accent lighting, task lighting, and general lighting in residential and commercial settings. They are also used in automotive lighting, aviation lighting, and street lighting. LED bulbs can be installed in recessed or surface-mounted fixtures and are commonly used for retrofitting existing lighting systems to improve energy efficiency. LED luminaires can come in various shapes and sizes, including bulbs, tubes, panels, and strips.

LED luminaires work by converting electrical energy into light through the use of light-emitting diodes (LEDs). LED luminaires require a driver to regulate the electrical current and voltage to the LEDs. An LED luminaire works by using an LED (Light Emitting Diode) as the light source. The LED is a semiconductor device that receives regulated DC power and emits light through a process called electro-luminescence. The luminaire may also include additional components to improve efficiency, performance, and appearance.

Features of LED lighting include:

• Energy efficient using much less energy than traditional incandescent lighting. Up to 90% of energy is converted into light, which can help to reduce energy costs and greenhouse gas emissions.
• Long lifespan lasting up to 50,000 hours or more, which is significantly longer than incandescent or fluorescent bulbs and reduces the frequency of replacements and maintenance costs.
• Versatile: LEDs come in a wide range of colours, sizes, and shapes and can be used for a variety of applications, from decorative lighting to task lighting and outdoor lighting.
• Durable and able to withstand shocks, vibrations, and extreme temperatures without breaking or burning out, making them suitable for outdoor and industrial lighting applications.
• Instantly on/off and do not require warm-up time. 
• High initial cost although the long-term energy savings can offset this cost.
• Limited dimming as some LED bulbs are not compatible with dimmer switches. This is changing with the development of new technology.
• Blue light emitted by LED lighting may result in potential health effects, although this can be addressed with the use of warm white LED bulbs.

Activity

Fluorescent Lighting

Fluorescent luminaires are commonly used in commercial and industrial settings due to their high efficiency and long life. They are used for general lighting, task lighting, and accent lighting in offices, schools, hospitals, and warehouses. Fluorescent luminaires are also used for plant growth and aquarium lighting. They come in various sizes and shapes, including tubes, compact bulbs, and high-intensity discharge (HID) lamps. Fluorescent lighting fixtures can be recessed or surface-mounted.

A fluorescent luminaire works when an electrical current is passed through the electrodes at either end of a gas-filled glass tube. This current excites the gas, causing it to emit ultraviolet (UV) light. The UV light interacts with a phosphor coating on the inside of the glass tube, causing it to emit visible light. The phosphor coating determines the colour temperature of the light. The visible light is emitted evenly across the surface of the glass tube, creating a uniform light output. The luminaire may also include a reflector to improve light distribution and efficiency. The electrical current is regulated by a ballast, which helps to maintain a stable current and prevent flickering. The ballast may be either an electronic or magnetic type, depending on the design of the luminaire.

Features of fluorescent lighting include:

• Energy efficient, converting up to 75% of energy into light thus reducing energy costs and greenhouse gas emissions.
• Long lifespan lasting up to 10,000 hours or more, reducing the frequency of replacements and maintenance costs.
• Versatile - the variety of shapes and sizes makes them suitable for a wide range of applications.
• Dimmable: Some fluorescent bulbs are compatible with dimmer switches, allowing for customisable lighting levels.
• Large area coverage - the broad, even light emitted is well-suited to large areas, such as office spaces and warehouses.
• Harsh or unnatural-looking lighting. 
• Mercury content which can be harmful to the environment if not disposed of properly.
• Flickering and humming noise can be distracting or irritating.

Halogen Lighting

Halogen lighting is often used for outdoor lighting, as well as in retail and commercial settings. It can also be used for accent lighting such as in track lighting or spotlights; task lighting applications, such as in desk lamps or under-cabinet lighting; display lighting especially where high colour rendering and dimming capability are required; and automotive lighting. Halogen bulbs can be installed in recessed or surface-mounted fixtures. Halogen luminaires come in various shapes and sizes, including bulbs, capsules, and spotlights.

Halogen luminaires are similar to incandescent luminaires but use halogen gas to improve their energy efficiency and lifespan. They work by passing an electric current through a tungsten filament, which is housed in a small quartz capsule filled with halogen gas. The heat from the filament causes the halogen gas to react with the tungsten atoms, creating a tungsten-halogen cycle that regenerates the filament and increases its lifespan. The halogen gas also helps to keep the quartz capsule clear of tungsten deposits, ensuring a consistent and bright light output. The visible light emitted by the halogen bulb is bright and clear, with a high colour rendering index (CRI).

1. Bulb
2. Halogen filled capsule
3. Tungsten filament
4. Capsule support
5. Base
6. Contact

Features of halogen lighting include:

• High-quality, bright, clear light with a high CRI, which means that colours are rendered accurately and vividly.
• Dimmable - compatible with dimmer switches, allowing for customisable lighting levels.
• Compact size that can fit into a variety of fixtures and applications.
• Instant on, immediately reaching full brightness.
• Energy inefficient.
• Short lifespan than other types of lighting, typically lasting around 2,000 hours.
• High heat generation which can make them unsuitable for certain applications.
• Fragile and easily broken.

High-Intensity Discharge (HID) Lighting

HID luminaires are commonly used in outdoor and industrial settings that require high-intensity lighting, including streetlights, automotive headlamps, horticulture and aquarium lighting, and security lighting. They can also be used for commercial and industrial lighting applications, such as in warehouses and factories.

HID or High-Intensity Discharge lighting operates by creating an electrical arc between two electrodes in a gas-filled bulb, which generates intense light. 

HID luminaires require a ballast to regulate the electrical current and voltage to the lamp. They come in various types, including high-pressure sodium (HPS), metal halide (MH), and mercury vapour lamps. 

Features of HID lighting include:

• High-intensity, bright light that can illuminate large areas effectively.
• Energy efficient, using less power to produce the same amount of light, as other bulbs.
• Long lifespan requiring less frequent replacement and reducing maintenance costs.
• Range of colour temperatures from warm white to cool white, making them suitable for different applications.
• High cost of installation and maintenance due to the ballast required for operation.
• Warm-up time before reaching full brightness.
• Environmental concerns as they contain toxic materials, such as mercury, which can be harmful if not disposed of properly.
• High cost. 

Activity

1. Summarise this information about types of lighting in the table in this worksheet.
2. Another recent lighting technology is Induction Lighting. Find out how this lighting operates and its applications.

Activity

Comparing light sources

In this activity you may wish to work with a partner. You will need three different types of light bulbs - incandescent, fluorescent, and LED, all the same wattage or brightness level.  

1. Turn off all other light sources in the room to create a controlled environment for the comparison.
2. Turn on each light bulb one at a time and observe the quality of light produced by each bulb. 
3. Note the following characteristics:
   • Brightness: how bright is the light produced by each bulb.
   • Colour temperature: is the light warm or cool? Does it have a yellowish or bluish hue?
   • Colour rendering: how well does the light reveal the true colours of objects?
   • Flicker: does the light appear steady or does it flicker
   • Glare: is the light too bright or too harsh to look at directly
4. Record your observations.
5. Compare your observations for each light source and note any similarities or differences. For example, you may note that the LED light produces a brighter and cooler light than the incandescent bulb, which has a warmer colour temperature.
6. Draw conclusions about which light source you think is the most effective and why, based on your observations. Consider factors such as energy efficiency, colour rendering, and cost.
7. Share your observations and conclusions on the class forum and discuss any differences in opinions or observations.

What we're covering:

• recessed luminaires
• surface mounted luminaires
• pendants
• tracks
• outdoors

Recessed luminaires

Recessed luminaires, also known as downlights, are light fixtures that are installed flush with the ceiling or wall, creating a streamlined and minimalist look. They are a popular choice for both residential and commercial applications due to their ability to provide a uniform and unobtrusive lighting solution.

Design and Construction

Recessed luminaires are constructed with a housing, a trim, and a light source. The housing is the body of the fixture and is installed into the ceiling or wall. The trim is the visible part of the fixture that covers the opening in the ceiling or wall and can come in a variety of styles and finishes to match the decor of the space. The light source is the bulb or LED module that provides the illumination.

Types of Recessed Luminaires

Fixed downlights are the most common type of recessed luminaires and are designed to provide a fixed beam of light in a specific direction.

Adjustable downlights are designed to direct the light in different directions.

Wall washers provide a wide beam of light that illuminates the entire wall, creating a soft and even illumination.

Pinhole downlights provide a small, focused beam of light that is ideal for highlighting artwork or other decorative features.

Applications

Residential lighting for general lighting, accent lighting, and task lighting e.g., providing general illumination in a living room, highlighting a piece of artwork in a hallway, or providing task lighting in a kitchen.

Commercial lighting spaces, such as offices, retail stores, and restaurants, to provide general lighting and accent lighting. They can also be used in outdoor applications, such as for lighting pathways or parking lots.

Hospitality lighting to provide a uniform and unobtrusive lighting solution that creates a relaxing and inviting atmosphere in hotels and resorts.

Healthcare lighting to provide a sterile and well-lit environment for medical procedures.

Surface-mounted luminaires

Surface-mounted luminaires are installed directly onto a surface, such as a ceiling or wall, rather than being recessed into it. They are popular in both residential and commercial applications due to their versatility, ease of installation, and ability to provide a wide range of lighting effects. 

Design and Construction

Surface-mounted luminaires are constructed with a housing, a light source, and a mounting bracket. The housing is the body of the fixture and can come in a variety of shapes, sizes, and materials to match the decor of the space. The light source is the bulb or LED module that provides the illumination, and the mounting bracket is the mechanism that attaches the fixture to the surface.

Types of Surface-Mounted Luminaires

Ceiling-mounted luminaires are the most common type of surface-mounted luminaires and are installed directly onto a ceiling. They come in a variety of shapes and sizes, including round, square, and rectangular, providing a range of lighting effects, such as diffused, direct, or indirect lighting.

Wall-mounted luminaires are installed directly onto a wall and can provide a range of lighting effects, including up-lighting, downlighting, and wall washing. They are commonly used in corridors, stairwells, and other areas where indirect lighting is desired.

Pendant luminaires are suspended from the ceiling and can provide a range of lighting effects, including diffused, direct, and indirect lighting. They are commonly used in dining areas, entryways, and other areas where a decorative lighting fixture is desired.

Applications

Applications are similar to recessed luminaires - residential lighting for general lighting, accent lighting, and task lighting; commercial lighting spaces; hospitality lighting; and healthcare lighting.

Pendant luminaires

Pendant luminaires, also known as hanging or suspension luminaires, are lighting fixtures that are suspended from the ceiling using a rod, chain, or cord. They are popular in both residential and commercial applications due to their versatility, aesthetic appeal, and ability to provide a range of lighting effects. 

Design and Construction

Pendant luminaires consist of a light source, a shade or diffuser, a suspension system, and a canopy. The light source can be an incandescent, fluorescent, or LED bulb or module and is usually located inside the shade or diffuser. The shade or diffuser is the decorative or functional component of the luminaire that helps to control the direction and intensity of the light. The suspension system consists of a rod, chain, or cord that attaches the luminaire to the ceiling, and the canopy is the decorative or functional component that covers the electrical box in the ceiling.

Types of Pendant Luminaires

Drum pendant luminaires are the most common type of pendant luminaires and feature a cylindrical or drum-shaped shade or diffuser. They come in a variety of materials, including fabric, glass, and metal, and can provide a range of lighting effects, from diffused to direct lighting.

Bowl pendant luminaires feature a bowl-shaped shade or diffuser and are commonly used in areas where direct lighting is required, such as over dining tables or kitchen islands. 

Linear pendant luminaires feature a long, narrow shape and are commonly used in commercial applications, such as offices and retail stores, to provide direct lighting over workspaces or displays.

Applications

Applications are similar to recessed luminaires - residential lighting for general lighting, accent lighting, and task lighting; commercial lighting spaces; hospitality lighting; and healthcare lighting.

Track luminaires

Design and Construction

Track luminaires, also known as track lighting or rail lighting, are lighting fixtures that are mounted on a track system. The track system consists of a long, straight bar or rail, typically made of metal, that is mounted to a ceiling or wall. The track features slots or grooves that allow the luminaires to be positioned along it and adjusted as needed.

They can contain one or multiple light sources, and can be adjusted to aim light where it is needed.  

Track luminaires offer several advantages over traditional lighting systems. They are highly versatile and can be used to create a wide range of lighting effects, from task lighting in retail and hospitality spaces, to accent lighting, to general room lighting. They can also be easily adjusted or repositioned, making them ideal for retail displays, art galleries, and spaces where lighting needs may change frequently.

Types of Track Luminaires

Spotlights are the most basic type of track luminaire, consisting of a single adjustable light source that can be directed to highlight specific areas or objects.

Floodlights feature a wider beam angle and are designed to provide general room lighting or to wash walls or artwork with light.

Pendant luminaires are suspended from the track system and are ideal for providing focused task lighting over a workspace.

Linear luminaires consist of a long, narrow light source that is ideal for creating a continuous strip of light along a wall or ceiling.

Applications

Track luminaires are used in a variety of settings, including homes, offices, retail stores, art galleries, museums, and restaurants. In homes, they are often used to highlight artwork, architectural features, or decorative accents. In offices, they can be used to provide task lighting for individual workstations or to highlight specific areas of a conference room or lobby. In retail stores, they are often used to highlight merchandise displays or to create a certain ambiance within the store.

Outdoor luminaires

Outdoor luminaires are lighting fixtures specifically designed for use in outdoor environments, such as parks, streets, parking lots, and buildings' exteriors. They are weather-resistant and typically installed on poles or mounted on buildings to provide sufficient illumination to outdoor spaces, enhance the aesthetics of outdoor areas, and improve safety and security. They can contain one or multiple light sources, and are often used for security lighting, pathway lighting, and accent lighting in residential, commercial, and hospitality settings.

Types of Outdoor Luminaires  

Area Lighting luminaires provide general illumination to large outdoor spaces, such as parking lots, parks, and outdoor events. They are typically mounted on poles and use high-intensity discharge lamps, such as metal halide or high-pressure sodium, to provide bright and uniform illumination over a large area.

Floodlights are high-intensity luminaires that illuminate a large area with a wide and bright beam of light. They are often used for security and safety purposes, such as illuminating large building exteriors, stadiums, and outdoor events.

Street lighting luminaires provide illumination to public roads and streets. These luminaires use LED, high-pressure sodium, or metal halide lamps, and are often mounted on poles along the roadside to provide sufficient illumination and safety to motorists and pedestrians.

Bollard lighting luminaires are low-level luminaires designed to illuminate pathways, walkways, and landscapes. These luminaires are typically installed at ground level and use LED lamps to provide soft and diffused lighting to enhance the beauty of the surrounding environment.

Wall pack luminaires are mounted on building walls and designed to illuminate the surrounding area with a broad, diffuse light. They are often used to light building exteriors, entrances, and exits.

Landscape lighting luminaires highlight and enhance outdoor spaces such as gardens, walkways, and water features. They use LED lamps and are often low-level fixtures designed to illuminate specific areas while providing subtle and soft lighting.

Activity

Answer the questions about lighting installations on this worksheet.  Email it to your tutor when you are done.

AS/NZS 3000:2018 - LIGHTING SYSTEM REQUIREMENTS 

AS/NZS 3000:2018 Electrical Installations (the Wiring Rules) outlines the requirements for the installation of electrical wiring and equipment in buildings, including lighting systems. As with any electrical installation carried out in New Zealand you must adhere to AS/NZS 3000:2018:

• Section 2 - General Requirements: This section outlines the general requirements for electrical installations, including the installation of luminaires, and provides guidance on their selection, placement and fixing.
• Section 3 - Selection and Erection of Equipment: This section covers the selection and erection of electrical equipment, including luminaires, and provides guidance on their suitability for the intended application.
• Section 4 - Protection for Safety: This section includes requirements for the protection of electrical installations against hazards, such as fire and electric shock, and includes guidance on the installation of luminaires in hazardous locations.
• Section 5 - Selection of Cables and Conductors: This section provides guidance on the selection of cables and conductors for electrical installations, including those used for lighting.
• Section 6 - Earthing and Bonding: This section covers the requirements for earthing and bonding of electrical installations, including lighting installations, to ensure electrical safety.
• Section 7 - Special Installations or Locations: This section provides guidance on the requirements for electrical installations in special locations, such as swimming pools, hazardous areas, and outdoor installations, including the installation of luminaires and lighting requirements.
• Section 8 - Energy Efficiency: This section provides guidance on the selection of energy-efficient luminaires and lighting systems, including the installation of LED lighting and lighting controls, to reduce energy consumption and operating costs.

You should also refer to AS/NZS 3000 for information about:

• Minimum lighting levels required for different areas of a building, such as workspaces, public areas, and outdoor spaces. Guidance on lighting colour and uniformity is also provided. (See Section 2.4.4.4 and 2.4.4.5.)
• Luminaire installation requirements, including clearance distances from combustible materials, minimum mounting heights, and suitable fixing methods. 
• Emergency lighting systems requirements, including the types of luminaires that should be used and their placement.
• Testing and maintenance of lighting installations to ensure they remain safe and efficient. This includes regular cleaning, lamp replacement, and testing of emergency lighting systems. 
• Wiring systems for lighting installations to ensure they are suitable for the location and conditions of the installation and installed in accordance with the manufacturer's instructions.
• Wiring methods for lighting installations according to the location and conditions of the installation.
• Switching and control mechanisms appropriate to the situation and position, including switches, dimmers, and timers.   
• Environmental factors that affect lighting installations, such as temperature, humidity, and corrosive substances.
• Documentation and certification upon completion of the installation of lighting systems.

It is important to note that these are just some of the key requirements outlined in AS/NZS 3000, and that the standard should be consulted for full details on the requirements for the installation of lighting systems in New Zealand.

What we're covering:

• space, area and appliances
• practice for designing a lighting layout

Designing a lighting layout requires careful consideration of the space, the intended use of the area, and the available electrical resources. Planning a simple lighting layout involves the following steps:

• Determine the room or space to be lit: The size, shape, and function of the room will dictate the number and placement of lights required. (The surface area is the area of the floor or work surface that requires lighting and can be found by measuring the length and width of the space and multiplying them together.)
• Identify the purpose of the space: Based on the type of space, (office, warehouse, retail store, or outdoor area) and the intended use of the space. Different tasks require different lighting levels e.g., a warehouse may require lower lighting levels for general navigation, but higher levels for detailed inspection of products. 
• Calculate the required lighting level: Based on the specific needs of the space or from the NZ Standard for Interior Lighting (NZS 6703:1984) or the Illuminating Engineering Society (IES) Lighting Handbook. A summary is shown here. 

Type of Space	Recommended Lighting Level (lux)
Office	300-500
Conference room	300-500
Classroom	300-500
Library	300-500
Retail store	1000-1500
Supermarket	1500-2000
Warehouse	150-300
Factory/manufacturing	150-300
Gymnasium	200-500
Hospital	300-500
Restaurant	50-1000
Kitchen	300-500
Bathroom	100-300
Corridor	50-150
Stairway	100-150

A useful formula to calculate the required lighting level is:

• Choose the appropriate type of light fixture: Based on the intended use of the space and the aesthetics of the room. Light fixtures should be evenly spaced and positioned to provide uniform lighting throughout the space.
• Determine the number of light fixtures required: Depending on the size of the space and the desired lighting level. As a general rule, one light fixture per 10 square meters of space is a good starting point. Fixtures should be evenly spaced to avoid uneven lighting.
• Determine the height of the light fixtures: Depending on the type of fixture chosen and the ceiling height. In general, light fixtures should be placed at a height that provides even illumination of the space.
• Choose the appropriate light bulbs: Based on the type of light fixture and the desired colour temperature. Warm white (2700-3000K) is suitable for living spaces, while cool white (4000-5000K) is suitable for workspaces.
• Plan the electrical layout: Depending on the number and type of light fixtures chosen. Plan the electrical layout to ensure that the wiring and circuit breakers can handle the load.
• Ensure compliance with NZ electrical regulations: Including the Wiring Rules and the Electricity Safety Regulations. Lighting fixtures and bulbs should be energy-efficient and long-lasting to minimise energy consumption and maintenance costs.
• Install the light fixtures: According to the electrical layout plan. Test the lighting to ensure that it meets the required lighting level and aesthetics.

Example 1

Planning a lighting layout for a small living room in a typical New Zealand home.

• Determine the room or space to be lit: The room is a small living room with a floor area of 3.5m x 4m.
• Identify the purpose of the space: The living room is primarily used for relaxing and entertaining guests, so the lighting needs to create a warm and inviting atmosphere.
• Calculate the required lighting level: Based on the intended use of the space, we want to achieve a lighting level of 200 lux. Rearranging the formula: 
  
  Required light output = required illuminance x surface area
  = 200 x 14
  2800 lm

• Choose the appropriate type of light fixture: For this living room, we'll use a combination of recessed downlights and a pendant light. The recessed downlights will provide ambient lighting, while the pendant light will serve as a focal point and provide a warm and inviting glow.
• Determine the number of light fixtures required: We'll install six recessed downlights and one pendant light. The six downlights will be evenly spaced in two rows of three, with each row centred on the long walls of the room. The pendant light will be centred over the seating area.
• Determine the height of the light fixtures: The recessed downlights will be installed in the ceiling at a height of 2.4m, while the pendant light will be installed at a height of 1.8m above the floor.
• Choose the appropriate light bulbs: For the recessed downlights, we'll use 9W LED bulbs with a warm white colour temperature of 2700K. For the pendant light, we'll use a 40W incandescent bulb with a warm white colour temperature of 2700K.
• Plan the electrical layout: The six downlights will be wired in two circuits of three, each on a 10A breaker. The pendant light will be wired on a separate 10A breaker.
• Ensure compliance with NZ electrical regulations: The wiring and electrical layout will be designed and installed in compliance with the Wiring Rules and the Electricity Safety Regulations.
• Install the light fixtures: The recessed downlights will be installed in the ceiling using cut outs that are 90mm in diameter. The pendant light will be installed in the centre of the room using a ceiling rose. All light fixtures will be wired and connected to the appropriate circuit breakers.

Example 2

Lighting Plan for an Office Space

• Determine the space to be lit: The space to be lit is a small office with a floor area of 4m x 4m.
• Identify the purpose of the space: The office space is primarily used for work, so the lighting needs to be bright enough to allow for reading, writing and computer work.
• Calculate the required lighting level: Based on the intended use of the space, we want to achieve a lighting level of 500 lux. Using the formula:
  

We can calculate the required light output as:
Required light output = Required illuminance x surface area
= 500 x 16
= 8000 lumens

• Choose the appropriate type of light fixture: For this office space, we'll use a combination of recessed downlights and desk lamps. The recessed downlights will provide ambient lighting, while the desk lamps will provide task lighting.
• Determine the number of light fixtures required: We'll install six recessed downlights and two desk lamps. The six downlights will be evenly spaced in two rows of three, with each row centred on the long walls of the room. The desk lamps will be placed on the desk at the appropriate position.
• Determine the height of the light fixtures: The recessed downlights will be installed in the ceiling at a height of 2.4m, while the desk lamps will be placed on the desk at a height of approximately 40cm above the work surface.
• Choose the appropriate light bulbs: For the recessed downlights, we'll use 12W LED bulbs with a cool white colour temperature of 4000K. For the desk lamps, we'll use 9W LED bulbs with a cool white colour temperature of 4000K.
• Plan the electrical layout: The six downlights will be wired in two circuits of three, each on a 10A breaker. The two desk lamps will be plugged into power sockets and will have their own on/off switch.
• Ensure compliance with NZ electrical regulations: The wiring and electrical layout will be designed and installed in compliance with the Wiring Rules and the Electricity Safety Regulations.
• Install the light fixtures: The recessed downlights will be installed in the ceiling using cut-outs that are 90mm in diameter. The desk lamps will be placed on the desk and plugged into power sockets. All light fixtures will be wired and connected to the appropriate circuit breakers.

What we're covering:

• types and configurations of lighting switches

An electric lighting circuit can be as simple as one light and one switch, but it can also be configured with multiple lights and switches. To accommodate these different configurations, manufacturers produce a variety of switch types for lighting circuits, including one-way (single pole), two-way (two pole), intermediate, and double pole.

These switches can also be used in other applications where the same device needs to be controlled from multiple locations. One-way switches can be used to control fans or pumps from a single location, while two-way and intermediate switches can be used to control motorised curtains and blinds, from multiple locations.

One-way switches

A one-way light switch is a standard SPST switch. It controls the flow of electricity to a single circuit from a single location and has a simple on/off mechanism. The 'one way' switch makes contact in one position only.  

Watch this video demonstrating how to wire a lighting circuit.

Basics: Wiring a Lighting Circuit

Also refer to NZECP 51:2004 (Electrical Work), Figure 3 which shows the wiring diagram for a 1-way lighting circuit.

Two-way switches

A two-way switch is like combining two, one-way switches into one. 

The two-way light switch is a standard SPDT switch with three terminals. The three terminals are usually named COM, L1 and L2. In one position, the COM and L1 terminals are connected, while in the second position, the COM and L2 terminals are connected. (All three terminals of a two-way switch cannot be connected simultaneously.)

This type of connection is typically called a “break before make” design, as the first connection must be broken before making the second connection. This contrasts with a regular two terminal switch, which is just a make-or-break device.

Two-way light switches are commonly used in hallways or staircases where two switches are required to control the same light. In this case, one switch is located at the top of the stairs and the other at the bottom. When the switch at one location is flipped, the light turns on or off, and the other switch mirrors the action.

Watch the videos explaining two-way switching and how to wire a 2-way switch.

• Two Way Switching Explained - How to wire 2-way light switch
• How To Wire a 2 Way Switch

Also refer to NZECP 51:2004 (Electrical Work), Figure 4, which shows the wiring diagram for a 2-way lighting circuit where 1 light is being controlled by 2 light switches. Could you explain this drawing to someone?

Intermediate switches 

An intermediate switch is a type of electrical switch used in a multi-way switching circuit, i.e., a circuit that allows you to control a single light or group of lights from multiple locations. When you have three switches controlling one light, the switch in the middle will always be an intermediate switch (and the others need to be two way).

An intermediate switch, also known as a three-way switch, works as a DPDT (double-pole, double-throw) switch. The intermediate switch does not have an 'off' position and is designed with four terminals that enable the switch to connect two active wires and two load wires in different ways, depending on the position of the switch. When the switch is toggled, it alternates the supply between the two sets of wires, allowing the light or device to turn on or off from different locations. In other words, the intermediate switch acts as a bridge between the other switches in the circuit, allowing them to communicate with each other and control the light or device together.

Double pole

A double pole switch has two separate circuits that can be controlled independently with one switch. It works by having two sets of contacts that can be toggled to either connect or disconnect the circuits. When the switch is turned on, both circuits are connected, allowing electricity to flow through both. When the switch is turned off, both circuits are disconnected, breaking the flow of electricity. Double pole switches are often used to control high-power devices or appliances, such as electric water heaters or air conditioners, as they can handle higher voltage and current than a single pole switch.

A double pole single throw (DPST) switch controls two circuits (poles) and has 2 states an “on” (closed) state and an “off” (open) state. It has four terminals in total, two inputs and two outputs which are all controlled by the same switch.

A double pole double throw (DPDT) switch is connected to two different circuits, each input can be connected to either of the outputs with six terminals in total, the two inputs and 4 outputs. These types of switches have 3 states; open (off), circuit 1 closed and circuit 2 closed. There are 4 contacts in total.

Activity

From the videos you will know there is more than one method to make a two-way switch connection. Two different methods are shown here. 

Standard Two-Way Switch Wiring (3-Wire Control)

Two-Way Switch Wiring (2-Wire Control) 

Find out which method is used in New Zealand and why it is preferred.

What we're covering:

• loop at the light configuration
• loop at the switch configuration

The method selected for wiring lighting circuits will depend on the wiring system employed. The two most effective configurations when installing lighting circuits are: 

Loop at the Light - In loop at the light wiring, the power source is first connected to the light fixture and then to the switch. A twin and earth power feed is run from the switchboard to the first light on the circuit. A twin active wire is run from the light to the controlling switch. The power feed is then looped from the first light to the second light on the circuit, and this process is repeated for all the lights on the circuit. The live and switched live wires are connected in a loop at the light fixture, forming a complete circuit.

Loop at the switch - In loop at the switch wiring, the power source first connects to the switch, and then it goes to the light fixture. The wiring forms a loop at the switch, where the live and switched live wires are connected in a loop. This system is used to avoid using two different types of cable, with the power feed looped at each switch. A twin and earth cable is run from the switch to the light. Careful planning is required to ensure that the number of conductors joined behind the switches does not exceed the recommended limit.

Watch the video discussing the two techniques for wiring – ‘looped at the light’ and ‘looped at the switch’.

How is your house wired Australia

Activity

Loop at the Light Circuit Activity

1. Draw a light fixture in the centre of the paper.
2. Next, draw a line extending from the light fixture to represent the cable that carries the power.
3. Draw the switch on your paper, with two lines extending from the switch to represent the cables that connect it to the light fixture.
4. Draw a loop in the cable near the light fixture, with the live and switched live wires connected together in a loop.
5. Label the light fixture, switch, and cables on your drawing.   

Loop at the Switch Circuit Activity

1. Draw a diagram of the loop at the switch wiring method on your paper. 
2. Draw a light fixture in the centre of the paper.
3. Draw the switch on your paper, with two lines extending from the switch to represent the cables that connect it to the light fixture.
4. Draw a loop in the cable near the switch, with the live and switched live wires connected together in a loop.
5. Draw a line extending from the light fixture to represent the cable that carries the power.
6. Label the light fixture, switch, and cables on your drawing.   

Finally, draw wiring diagrams for each circuit. Label each component and wire in your diagrams and explain how the wires are connected to each other. Email both diagrams to your tutor.

Activity

Answer the following questions from today’s session:

1. What is the term for the wiring method used to connect lighting circuits using a twin and earth cable from the light fitting to the switch? 
2. What determines the maximum number of lights that can be controlled by a one-way loop at the light switch? 
3. What combination of switches is required to independently control a set of stairway lights from four different locations? Explain your choice.
4. Is it possible to use a manufacturer's standard switch for two-way switching? Explain your answer.
5. What switching circuit would be the most suitable to control lights on three flights of stairs? Explain your choice.

Email your answers to your tutor.