Technical Information

Lighting & Dimming Technology

Derating - Reducing the capacity of a control when multiple dimmers are installed in the same back box or under the same frame.

Electronic low-voltage – Track lights are usually electronic low voltage. Control these lamps with electronic low-voltage (12v) dimmers only.

Fade time - The time it takes all zone/channels to fade from one lighting scene to another with all zones/channels arriving at the next scene at the same time.

Gang Single-gang - one control mounted in a single wallbox.

IR (Infra Red) - Type of remote control technology.

Multigang - two or more controls mounted side-by-side in a series of connected wallboxes.

Magnetic Low-Voltage – Recessed lights are often magnetic low voltage. Magnetic low voltage lights tend to be larger and heavier than electronic low voltage.

Multi-location dimming - Allows full-range dimming from two to ten locations.

Preset Dimmer - Preset dimmers have a built-in on/off switch that allows the user to turn lights on to a pre-selected light level.

Radio frequency interference (RFI) - An audible buzz or noise in some sensitive audio and radio equipment caused by the dimmer's rapid current switching in conjunction with sharp current rise.

Raise/lower Controls - An actuator (slider, rocker, toggle, paddle, etc.) which when engaged increases or decreases the intensity of light controlled, then returns to its normal place of rest after disengaging.

Scene - The lighting effect created by adjusting several zones/channels of lighting to the desired intensity.

Single pole - A single pole dimmer provides full-rangedimming from one location only.

Slide-to-off dimmer - Slide-to-off models have an on/off switch activated at the bottom of the linear slide travel.

2-way - 2-way dimming control allows dimming or switching from one location (using a 2-way dimmer) and on/off switching from a second location (using a 2-way switch).

Two-location dimming - Allows full-range dimming from two different locations.

Wallbox Dimmer - A self-contained dimmer that fits into a wallbox.

Zone - A fixture or group of fixtures controlled simultaneously as a single entity.

Electrical Window Treatments

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Answers to common questions about dimmers

What kind of dimmers do I use with my low voltage transformers?
Low voltage lighting uses a transformer that is with magnetic or electronic. Use Lutron universal dimmers ti control both. We recommend Lutron transformers designed specifically for electronic low voltage applications.

Can I replace my existing switch?
Yes. You can replace a switch with a dimmer, just as you would another switch.

What are the dimensions of the dimmer?
86mm x 86mm.

Do I need any special cable to install a dimmer?
No. You just use the existing two to make the connection.

How do I prevent lamps with dimmers from flickering or buzzing?
This is a problem to with lamps or transformers you use and the electrical load. You will need to identify the part number of your dimmer.

Can using dimmers save money?
Dimmers save energy and increase the life of your light blue so they are friendlier to the environment and to your pocket.

Dimming Saves Electricity Bulbs last longer
10% 10% 2 Times Longer
25% 20% 4 Times Longer
50% 40% 20 Times Longer
75% 60% >20 Times Longer


In today’s hectic working environment, more and more employees are required to work indoors. As a result the number of complaints arising from working under fluorescent lighting has risen dramatically.

Problems such as headaches and eyestrain are a major contributory factor in many stress related illness. This type of stress can ultimately lead to poorer performance and even absenteeism, a costly expenditure for any company.

DAYSTAR Long life fluorescent lamps have been designed as a compatible light source for your working environment, providing a high quality light, which not only improves working conditions, but also reduces maintenance costs. This pure white, vibrant lamp has a spectral distribution, which closely resembles the quality of light that can be seen on a clear sunny spring day.

Therefore staff working under DAYSTAR lamps can be kept visually and mentally more alert!


DAYSTAR lamps have been designed to operate at a colour temperature of 6500K (Kelvin), the same colour as the majority of European VDU monitors. Standard fluorescent lighting operates at a lower colour temperature (between 2700K and 4000K) this creates a colour imbalance, which the sensitive human eye detects and attempts to correct.

It is precisely this constant adjustment that causes visual discomfort ( S.A.D). In addition the DAYSTAR has a colour rendition of (98CRI). This can be compared to natural daylight, which has a CRI of 100. These characteristics make DAYSTAR the ideal fluorescent lamp for people requiring.


  • Reduced Eyestrain
  • Improved Concentration
  • Increased Productivity
  • Excellent Visual Comfort
  • Long life 15,000 rated hours
  • Less headaches Less Fatigue
  • Increased work safety
  • Enhanced Working Environment
  • Stimulates Plant Growth
  • Direct Retro-Fit of your
  • Fluorescent lamps

  • Offices
  • VDU Work Stations
  • Car Showrooms
  • Printers
  • Carpet Showrooms
  • Retail Outlets
  • Hospitals/ Dentists
  • Banks
  • Art Galleries
  • Training & Conference Rooms
  • Hairdressing Salons (for accurate colour rendition)
  • Control Rooms
  • Museums
  • Assembly Lines
  • Fitness Centres
  • Schools & Colleges


We all recognise natural daylight as a healthier and more comfortable light for work and leisure activities.

For much of the year the days are short and we depend on artificial light for both background and task illumination. Most lamps, whether Tungsten, Fluorescent or Halogen, nearly always emit a distorting yellow tinged glow.

Daylight lamps are made with a special blue tinted glass which produces a quality of light similar to natural daylight.


Arts and Crafts, Embroidery, Reading, Hobbyists ,Printing and combating the effects of seasonal Adjusted Disorder.


Nowadays, selecting the right bulb (lamp) for your light fittings means knowing what basic type you want, what wattage, bulb shape and end cap type will suit the fitting, whether you want clear, pearl or coloured glass and what the lit bulb (lamp) will look like. You also have the opportunity to cut your lighting bills by selecting low-energy bulbs. These cost more to buy initially but last a lot longer and cost a lot less to run in the long term.

Lampholder Types

Whatever type of bulb you want to use, it's end cap must match the lamp holder into which it will be fitted. Most lamp holders in general use take Bayonet cap (BC) bulbs with two side pins. Some, especially spotlight fittings, have Edison Screw (ES) lamp holders and take bulbs (lamps) with threaded end caps. Compact light fittings may require bulbs (lamps) with smaller end caps of either type; these are called Small Bayonet Cap (SBC) and Small Edison Screw (SES). Look out for an illustration of the cap type on the bulb (lamp) packaging.


Lamps of different types come in a range of wattage's. The higher the wattage the brighter the lamp, so select the wattage to get the lighting level you need.


These are the lamps in everyday use, especially in fittings where the lamp is not visible to the naked eye. There are two common shapes; standard pear and squared-off pear, (sometimes known as GLS). Both Bayonet Cap and Edison Screw types are available, and standard wattage's are 25, 40, 60, 100, 150 watts.
Use clear lamps in cut glass ceiling lights or within enclosed fittings with translucent covers.

  • When using coloured lamps (usually rated at 25 watts) they can be used out of doors only if fitted in special waterproof lamp holders.
  • Use pearl lamps in shaded ceiling and table lamps.
  • Use squared-off pear lamps in any fitting where you want to cast very soft lighting tones. They are available in plain white or in soft light
  • colours-pink, peach, beige, blue or green- to enhance the room's decor.
  • Use pygmy lamps (usually rated at 15 watts) in compact fittings and cabinet display lights.


These are lamps designed to be on show or to be used where the lamp forms part of the design of the light fitting.

  • Use large globes in pendent fittings, standard lamps and large table, lamps, with or without a shade. They come in white and soft light colours, are rated at 100 watt, have a Bayonet Cap and have different diameters.
  • Use small round lamps in table and wall lights and around make-up mirror. They are available in clear, white or soft light colours, are rated at 25, 40, or 60 watts, and come in Bayonet Cap, Small Bayonet Cap or Small Edison Screw types.
  • Use candle lamps in wall lights and multi-lamp ceiling fittings. Choose plain candles in white or soft-tone colours for shaded fittings, and twisted bent tip or flambeau candles where the lamp will be on show. Clear candles bring added glitter to cut glass chandeliers. Standard wattage's are 25, 40 and 60 watts.


Reflector or spotlight lamps are used in spotlight fittings and in some desk and standard lamps to cast a strong directional beam of light. They are available in Edison Screw or Bayonet End Caps.

  • Wattage's range from 30 to 150 watts, and lamp widths from 39 to 95mm, making it essential to match bulb size to fitting carefully.
  • Use crown-silvered Sphere or Pear lamps in fittings containing a reflector. The light is reflected back into the fitting to create a sharp, narrow beam with minimal glare. Standard wattage's are 40 and 60 watts.
  • Use pressed glass (PAR or Parabolic Aluminised Reflector) lamps in outdoor fitting's. PAR lamps have Edison Screw caps only, and come in 80 and 120 watts.


Also known as compact fluorescent lamps, these low-energy lamps contain miniature fluorescent tubes. They cannot be used in fittings controlled by dimmers, electronic time switches, PIR devices or photoelectric (dusk to dawn) switches.
  • Use electronic PLEC or PLET types in place of general-purpose lamps, especially in fittings left on for long periods or where high-wattage lamps cannot be used without overheating the fitting.
  • Use globe and domed cylindrical types in unshaded fittings normally taking a standard 100 watt lamp.
  • Use enclosed (comfort) types in utility areas such as garages, workrooms and in outdoor light fittings.
Each is equivalent to a general-purpose lamp of between 4 and 5 times the wattage.

Passive intra-red sensors

Switches as a result of detecting movement. The user sets the lux level so that the lights will only switch on when the ambience falls below this predetermined level.

Presence Sensor

  • Passive infra-red detector
  • Ceiling mounted
  • 200-250 V AC 50Hz stand alone switch
  • 1st & 2nd fix capability
  • Flush fitting
  • Adjustable Timer
  • Adjustable Photocell
  • 6amp switching
  • Pre-wired cable
  • Fitted plug
  • Walk test LED
  • SELV operation
  • Over-ride facility

Lighting Glossary (Terms & Language)

Apparent Colour

Of a light source, subjectivity the hue of the source or of a white surface illuminated by the source; the degree of warmth associated with the source colour. Lamps of low correlated colour temperature are usually described as having a warm apparent colour, and lamps of high correlated colour temperatures as having a cold apparent colour.

Aspect Factor

A function of the angle subtended at a point by the length of a linear source, and of the axial distribution of luminous intensity from the source; used in the calculation of luminance at a point.

BZ (British Zonal) System

A system for classifying luminaries as described in CIBSE Technical Memorandum No.5. The BZ class number (e.g. BZ3) denotes the classification of a luminaire in terms of the flux from a conventional installation directly incident on the working plane, relative to the total flux emitted below the horizontal (the direct ratio).

Candela (CD)

The SI unit of luminous intensity, equal to one lumen per steradian.

Cavity index (CI)

A term, indicating the proportions of boundary surfaces, used in determining the effective reflectance's of room surfaces for interior lighting design: defined for cavity of length L, width W, and depth d, as LW/(d (L+W)).


In the Munsell system, and index of saturation of colour ranging from 0 for natural Grey to 16 for strong colours. A low chroma implies a pastel shade.


The colour quality of stimulus usually defined by coordinates on a plane diagram in the colorimetric system (IE publication 15) or by the combination of dominates wavelength and purity.

Colour Rendering Index (RI)

A measure of the degree to which the colours of surfaces illuminated by a given light source conform to those of the same surfaces under a reference illuminate, suitable allowance having been made for the state of chromatic adaption. (CIE Publication 13.2)

Colour Temperature

The temperature of a full radiator, which emits radiation of the same chromaticity as the radiator being considered.

Correlated Colour Temperature (Unit:K)

The temperature of a radiator which emits radiation having a chromaticity nearest to that of the light source being considered, e.g. the colour of a full radiator at 3500K is the nearest match to that of a white tubular fluorescent lamp.

Daylight Factor

The luminance received at a point indoors, from a sky of known or assumed luminance distribution, expressed as a percentage of the horizontal luminance outdoors from an unobstructed hemisphere of the same sky. Direct sunlight is excluded from both values of luminance.

Design Service Luminance

The service luminance in the lighting specification. Design service luminance is derived from the standard service luminance by taking account of the modifying factors in the flow chart.

Diffused Lighting

Lighting in which the luminous flux comes from many directions, none of which predominates.

Direct Lighting

Lighting in which the greater part of the luminous flux from the luminaries reaches the surface (usually the working plane) directly, i.e. without reflection from surrounding surfaces. Luminaries with a flux fraction ratio of less than 0.1 are usually regarded as direct.

Disability Glare

Glare which impairs the ability to see detail.

Discomfort Glare

Glare which causes visual discomfort.

Downward Light Output Ratio (DLOR)

The ratio of the total light output of a luminaire below the horizontal under stated practical conditions to that of the lamp or lamps under reference conditions.

Emergency Lighting

Lighting provided for use when the main lighting installation fails.

Escape Lighting

Emergency lighting provided to ensure that the means of escape can be safely and effectively used at all material times.


A visible oscillation in luminous flux.

Flux Fraction

The proportion of luminous flux emitted from a luminaire in the upper or lower hemisphere (upper and lower flux fraction).

Flux Fractions Ratio (FFR)

The ratio of the upward luminous flux to the downward luminous flux from a luminate. It is also the ratio of the upper flux fraction to the lower flux fraction and the ratio of the upward light output ratio to the downward light output ratio.

General Lighting

Lighting designed to illuminate the whole area uniformly, without provision for special local requirements.

General Surround Lighting

Lighting designed to illuminate the non-working parts of a working interior.


The discomfort or impairment of vision experienced when parts of the visual field are excessively bright in relation to the general surroundings.

Hazardous Environment

An environment in which a risk of fire or explosion exists.

Luminance (E)(Unit: Lm/m², LUX)

The illuminous flux density at a surface, i.e. the luminous flux incident per unit area. (This quantity was formally known as the illumination value or illumination level).

Initial Light Output (Unit:Lm)

The luminous flux from a lamp after 100 hours of operation.

Installed Efficacy (Unit:Lm/W)

A factor, which quantifies the efficiency of a lighting installation in converting electrical power to light. Specifically it is the product of the lamp circuit luminous efficacy and the utilization factor.

Isolux Diagram

A diagram showing contours of equal luminance.

Lamp Lumen Maintenance Factor (LLMF)

The proportion of the initial light output of the lamp that is produced after a set time.

Light Loss Factor (LLF)

The ratio of the luminance provided by the installation at some stated time, with respect to the initial luminance, i.e. that after 100 hours of operation. The light loss factor is the product of the lamp lumen maintenance factor, the luminaire maintenance factor and the room surface maintenance factor.

Light Output Ratio (LOR)

The ratio of the total light output of a luminaire under stated practical conditions to that of the lamp or lamps under reference conditions. For the luminaire, the output is usually measured in the designated operating position at 25°C ambient temperature with control gear of the type usually supplied in a luminaire and operated at its normal voltage. For the lamp the output is measured at 25°C ambient temperature and with control gear of standard properties. This is a practical basis for evaluating the total light output to be expected under service conditions.

Lighting Design Lumens (LDL) (Unit:Lm)

Lamps vary in flux output, both between themselves and through their operating lives. The lighting design lumen is a nominal value, which is representative of the average light output of each type or size of lamp throughout its life.

Load Factor

The ratio of the energy actually consumed by a lighting installation over a specified period of time to the energy that would have been consumed had the lighting installation always been operating during the period of time.

Local Lighting

Lighting designed to illuminate a particular small area which usually does not exceed far beyond the visual task, e.g. a desk light

Localized Lighting

Lighting designed to illuminate an interior and at the same time to provide higher luminance over a particular part or parts of the interior.

Lumen (Lm)

The SI unit of luminous flux, used in describing a quantity of light emitted by a source or received by a surface. A small source which has a uniform luminous intensity of one candela emits a total of 4 lumens in all directions and emits one lumen within solid angle (Steradian)


An apparatus which controls the distribution of light given by a lamp or lamps and which includes all the components necessary for fixing and protecting the lamps and for connecting them to the supply circuit. Luminaire has superseded the term light fitting.

Luminaire Maintenance Factor (LMF)

The lumen output from a luminaire declines with time because of dirt deposition on and in the luminaire. The luminaire maintenance factor quantifies this decline; being the proportion of the initial light output from the luminaire that occurs after a set time, allowance having been made for the decline in light output from the lamp.

Luminance (L)(Unit: Cd/m²)

The physical measure of the stimulus, which produces the sensation of brightness measured by the luminous intensity of the light, emitted or reflected in a given direction from a surface element, divided by the area of the element in the same direction. The SI unit of luminance is the candela per square metre; the relationship between luminance and luminance is given by the equation.

Luminous Efficacy (Unit:Lm/W)

The ratio of the luminous flux emitted by a lamp to the power consumed by the lamp. When the power consumed by control gear is taken into account this term is sometimes known as lamp circuit luminous efficacy and is expressed in lumens/circuit watt

Luminous Efficiency

The ratio of the radiant flux weighted according to the CIE Standard Photometric Observer to the corresponding radiant flux.

Luminous Flux (Unit:Lm)

The light emitted by a source, or received by a surface. The quantity is derived from radiant flux by evaluating the radiation in accordance with the spectral sensitivity of the standard eye as described by the CIE Standard Photometric Observer.

Luminous Intensity (Unit:Cd)

A quantity, which describes the power of a source or illuminated surface to emit light in a given direction. It is the luminous flux emitted in a very narrow cone containing the given direction divided by the solid angle of the cone: the result is expressed in candelas.

Luminous Intensity

The distribution of the luminance provided by an installation in the average condition of dirtiness expected in service, to the luminance from the same installation when clean. The maintenance factor is always less than unity, 1.

Mounting Height

Usually the vertical distances between a luminaire and the working plane, but sometimes the distance between the luminaire and the floor.

Operating Efficacy (Unit:Lm/W)

A term, which qualifies the efficacy of a lighting installation in use. Specifically operating efficacy is the quotient of the installed efficacy of the installation and the load factor.

Power Factor

In an electric circuit, the power factor is equal to the ratio of the root mean square power in watts to the product of the root mean square values of voltage and current; for sinusoidal waveforms the power factor is also equal to the cosine of the angle phase difference between voltages and current.

Room Index (RI)

An index related to the dimension of a room and used when calculating the utilization factor and other characteristics of the lighting installation:


Room Index =




Where L is the length of the room, W the width and hm the height of the luminaries above the working plane.


Room Surface Maintenance Factor (RSMF)

The proportion of the luminance provided by a lighting installation in a room after a set time compared with that which occurred when the room was clean, allowance having been made for the deposition on luminaries.

Service luminance

The mean luminance throughout the maintenance cycle of an installation, averaged over the relevant area. The area may be the whole of the working plane or just the area of the visual task and its immediate surround, depending on the lighting approach used.

Spacing to Height Ratio (SHR)

This ratio describes the distance between luminaire centres in relation to their height above the working plane. For a regular square arrangement of luminaries, it is the distance between adjacent luminaries divided by their height above the working plane More generally,

spacing/height ratio = (1/hm)Ö(A/N)

Where A is the total floor area, N is the number of luminaries and hm is their height above the working plane.

Standard Service Luminance

The service luminance recommended for the assumed standard conditions of the application, specified by the CIBSE guide.

Standby Lighting

Emergency lighting provided to enable normal activities to continue.

Steradian (SR)

The unit of solid angle. A complete sphere subtends 4 steradians from the centre.

Stroboscopic Effect

An illusion caused by oscillation in illuminous flux, that amkes a moving object appears to be stationary or as moving in a manner different from that which it is truly moving.

Upward Light Output Ratio (ULOR)

The ratio of the total light output of a luminaire above the horizontal under stated practical conditions to that of the lamp or lamps under reference conditions.

Utilization Factor (UF)

The proportion of the luminous flux emitted by the lamps, which reaches the working plane.

Working Plane

The horizontal, vertical, or inclined plane in which the visual task lies. If no information is available, the working plane may be considered to be horizontal and 0.7m above the floor for offices, horizontal and 0.85m above the floor for industry.

Emergency Lighting

In this the lamp is on all the time. Under normal conditions the mains power it directly or indirectly. Under emergency conditions, one of the lamps normally operated by the mains, is energized from it's own battery supply.

Emergency Lighting

In this the lamp is off when power is available to charge the batteries. Upon supply failure the lamp is energized from the battery pack.

Emergency Lighting

This is a hybrid of the previous two. A lamp provided which operates from the mains supply under normal conditions. Under emergency conditions a second lamp, not normally energized under mains operation, powered from the battery pack, takes over. Sustained luminaries are often used for exit signs. Systems of self-contained luminaries are the easiest and most flexible to install but their effective life is likely to be less than that of central battery systems. Also, maintenance and testing must be through if operation in the event of emergency is to be guaranteed.

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