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CLOSE THIS BOOKLighting Installation - Basic vocational knowledge (Institut fr Berufliche Entwicklung, 164 p.)
8. Lighting Fittings
VIEW THE DOCUMENT(introduction...)
VIEW THE DOCUMENT8.1. Protection Classes
VIEW THE DOCUMENT8.2. Degrees of Protection
VIEW THE DOCUMENT8.3. Efficiency of a Fitting
8.4. Kinds of Lighting Fittings
VIEW THE DOCUMENT(introduction...)
8.4.1. Functional Lighting Fittings for Indoor Lighting
VIEW THE DOCUMENT8.4.1.1. General Lighting Fittings
VIEW THE DOCUMENT8.4.1.2. Local Lamps
VIEW THE DOCUMENT8.4.1.3. Flameproof and Explosion-proof Lighting Fittings
8.4.2. Outdoor-Lighting Fittings
VIEW THE DOCUMENT8.4.2.1. Street Lighting Lanterns
VIEW THE DOCUMENT8.4.2.2. Decorative Outdoor-Lighting Fittings
VIEW THE DOCUMENT8.4.2.3. Floodlights and Spotlights
VIEW THE DOCUMENT8.4.3. Lighting Fittings for Representation Purposes and Housing Space
VIEW THE DOCUMENT8.4.4. Lighting Fittings for Special Purposes

Lighting Installation - Basic vocational knowledge (Institut fr Berufliche Entwicklung, 164 p.)

8. Lighting Fittings

Lighting fittings are devices serving the distribution, filtering and transformation of light emitted by lamps. They included all parts necessary for fitting, protecting and operating the lamps.

According to the effect of light it is distinguished between two main groups:

- Lighting fittings for illumination purposes
- Lighting fittings for light emission.

Within these groups, the actual subdivision is made according to the respective purposes of use. If one tried to designate all lighting fittings by these very few names, this would soon lead to difficulties of distinction. Therefore, further subdividing of lighting fittings is made, for instance by the mode of their installation or placing.

Table 23. Classification of the lighting fittings according to the ways of fixing

Stationary fittings

Built-in fittings

Ceiling fittings

Pendant lamps

Cord-adjusted suspended fittings

Wall fittings

Mounting fittings

Standing fittings

Fittings put on top of a holding structure

Fittings fixed by brace at a holding structure

Mobile fittings

Floor standard lamps

Standard lamps

All lighting fittings used for illumination purposes have to meet definite requirements as to lighting engineering, design, electrotechnical and mechanical qualities. These requirements have more or less importance according to the purpose the respective lamp shall fulfill. With domestic rooms and rooms for representation, for example, demands will be made mainly on the design of a lighting fitting. Shall the lighting fittings contribute to the interior decoration of a room, this is to say they shall be included in the architecture, demands of illumination engineering should rank first. With working lighting fittings, technical requirements are decisive and the design is subordinated to them. The term of working lighting fittings is not standardized, neither nationally nor internationally. However, it is used in this textbook for better distinction from domestic lighting fittings and those for representation purposes.

8.1. Protection Classes

The protective class of a lighting fitting indicates the protective measures or the integration into the protective measures against hazardous contact voltage during the installation of the lighting fitting.

All lighting fittings must be constructed in accordance with the protective classes I, II or III. For external marking on the lighting fitting, the symbol is used for protective class II, while symbol applies to protective class III.


Table 24. Electric lighting fittings

There is no special marking for lighting fittings belonging to protective class I.

The international trend goes to the application of protective class II to lighting fittings that can be installed and maintained by amateurs. This concerns especially the domestic lighting fittings. But also with working lighting fittings the use of the protective insulation leads to greater safety and, with some installations, even to material savings.

The protection classes mean:

Table 25. Degrees of protection of lighting fittings

Degree of protection

Application

I

Marks a lighting fitting equipped with a protective earth-terminal in addition to the operating insulation for protection against hazardous contact voltage.

II

Marks a lighting fitting equipped with an extra insulation in addition to the operating insulation for protection against hazardous contact voltage.

III

(There is no protective-earth terminal) It marks a lighting fitting designed for connection to protection low voltage.

8.2. Degrees of Protection

The degree of protection of a lighting fitting indicates the degree of protection in one or more protective systems. The following markings are used:

- Characteristic letters IP - for the degree of protection

- 1. characteristic numbers 0 to 6 - for the protective system of ‘protection against accidental contact and foreign matter’

- 2. characteristic numbers 0 to 8 - for the protective system of ‘water protection’

- Additional letter P - for partial accomplishing of a protective system.

Table 26. Protective systems of lighting fittings

Prot. system

First characteristic figure

Second characteristic figure


Protection against accidental contact

Protection against foreign matters

Protection against water

IP 20

against finger contact

against penetration of solid foreign bodies of a diameter > = 12.5 mm

no protection against water

IP 21



protection against harmful effects of vertically falling water drops in horizontal position of use of the test piece

IP 22



protection against harmful effects of vertically falling water drops also with an inclined position of the test piece by +-15 degrees from the horizontal position of use in two planes vertical to each other

IP 23



protection against the harmful effect of water in the form of rain falling in from all sides at an angle of 60 degrees compared with the vertical

IP 40

against contact with tools

against penetration of foreign bodies of a diameter > = 1.0 mm

see IP 20

IP 43



see IP 23

IP 44



protection against the harmful effects of splash from any direction

IP 50

complete protection against accidental contact

against detrimental deposition of dust inside

see IP 20

IP 54



see IP 44

IP 55



Protection against the harmful effects of water jets (hose-proof) from any direction

IP5p4


partial protection against deposition of dust

see IP 44

IP 65


against penetration of dust

see IP 55

IP 67



protection against harmful effects of water in case of overflowing in constant pressure and time conditions

IP 68


protection against penetration of water with temporally unlimited overflowing and definite pressure

Not all possible combinations are used in connection with lighting fittings. A selection can be made including the degrees of protection of the most commonly used lighting fittings.

The degree of protection of a lighting fitting is determined by the various operation conditions and the local conditions resulting from the use of the lighting fittings in differently endangered rooms. All lighting fittings are marked as to their respective degree of protection in documentations, device descriptions and on their rating plates.

8.3. Efficiency of a Fitting

The efficiency of a lighting fitting (operating efficiency of a lighting fitting) is the coefficient which indicates to what extent the luminous flux of the lighting fitting operated in the respective ambient temperature results from the luminous flux of the lamps placed in the lighting fitting.

Table 27. Minimum light output ratios of a number of commonly used lighting fittings

Type of reflector

Type of covering

Minimum efficiency

Fittings for filament lamps, high-pressure mercury vapour lamps, halogen metal vapour lamps and high-pressure sodium vapour lamps with a glare protection angle of 15...30°

mirror reflector

without covering

0.65


with clear glass covering

0.60

diffuse reflector

without covering

0.65


with clear glass covering

0.60


with opaque covering or spill shield

0.55

without reflector

with opaque covering

0.70

Fittings for fluorescent lamps with a glare protection angle of 15...30° across the longitudinal axis of the fitting

Diffuse reflector

without covering

0.60


with clear glass covering

0.55


with opaque covering or spill shield

0.50

Without reflector

without covering (no glare protection angle)

0.90


with clear glass covering (no glare protection angle)

0.80


with opaque covering or spill shield

0.65

8.4. Kinds of Lighting Fittings

In lighting engineering, application of lighting fittings for indoor and outdoor lighting as well as domestic lighting fittings and those for purposes of representation are of the greatest importance. By similar parameters such as equipment, fixing, degree of protection and field of application it is possible to categorize these lighting fittings under certain groups and to describe them. In order to make the text more instructive, pictures of the lighting fittings are inserted which represent only a small part of the extensive range of lighting fittings manufactured by industry and which can be considered as good solutions of construction.

Lighting fittings for special purposes such as vehicle lighting fittings, lighting fittings with own current source, lighting fittings for medical purposes, and those for photo and film shooting as well as for television are not treated.

8.4.1. Functional Lighting Fittings for Indoor Lighting

8.4.1.1. General Lighting Fittings

Lighting fittings the construction of which is such that they - after suitable arrangement - fully illuminate a room are called general lighting fittings. In industrial and social buildings many rooms are illuminated by these lighting fittings. Consequently, there is a very wide range of such fittings. It includes fittings for fluorescent lamps, high-pressure mercury vapour lamps, halogen metal vapour lamps and filament lamps with the protective systems of IP 20 to IP 67 and the degrees of protection I and II. Also the light-technical characteristic values are very diversified and specific according to the respective lighting tasks resulting from the technological process. All the lighting fittings stand out for high characteristic values as to lighting engineering, which are the basis of economical lighting installations.

The following lighting fittings are used to solve the tasks of general lighting:

Lighting fittings with fluorescent lamps for dry rooms

A universally applicable illuminator system for any kind of dry rooms is the combinational illuminator system structured according to the unit principle. Basic body is a trapeziform case that accommodates all electrical construction elements. It is manufactured internationally according to almost similar construction principles and is suited for the equipment with fluorescent lamps of 20, 40 and 65 watt.


Figure 43. Combination fitting, open

With the help of a similar basic element lighting fittings are realized with 1, 2 and 3 lamps.


Figure 44. Glare protection angle

By various glare protection shields which are fixed on the basic body a wide range of illuminators can be produced.


Figure 45. Combination fitting with various glare protection shields


Figure 46. Surface fittings

1 for panel mounting in the ceiling
2 for surface mounting on the ceiling

The diversified use of the lighting fittings is still enlarged by the different modes of suspension such as ceiling fittings and pendant fittings as well as individual and Christmas-tree pattern arrangements.

Another system of lighting fittings for dry rooms are the so called surface illuminators. These are lighting fittings, which due to their good design and the type of fixing as ceiling-mounted or built-in ceiling illuminators and due to their light-technical characteristic values are used mainly in social buildings and in rooms for representation purposes. As to the design, there are rectangular and square illuminators equipped with spill shields or plastic coverging. (See again Fig. 43).

They are equipped with fluorescent lamps. As a result of the cosine-shaped light distribution, a nearly even distribution of illumination can be achieved by a corresponding arrangement of the lighting fittings.

Environmental lighting fittings

The adverse effects of artificial lighting, especially the development of heat with high illumination intensity, shall be reduced or avoided by temperature-controlled lighting fittings.

The environmental lighting fittings offered by the manufacturers for fluorescent lamps and filament lamps are mainly integrated in the outgoing-air circle of the air-conditioning system. By this, the following major advantages are achieved:

- Better ambient temperatures are created within the illuminator; thus, optimal values of the luminous flux of the fluorescent lamps are achieved.

- The heat generated by the lamps is partially led out immediately. This leads to less heat in the room.

- The technical elements are less contaminated.

- The combination of lighting and air-conditioning enables a better utilization of the ceiling surface.

Environmental lighting fittings are manufactured mainly as built-in illuminators. These lighting fittings are built in according to three construction principles:

- Lighting fittings with forced air cooling of the lamp
- Lighting fittings cooled by circulating air
- Ventilated lighting fittings.

In order to avoid glare, the environmental lighting fittings are covered by spill shields or plastic screens, in general. The distribution of light intensity is concentrated or at a narrow angle.


Figure 47. Air-handling fittings

1 fittings with forced air-cooling of the lamps, 2 air-circulated fittings, 3 ventilated fittings

Lighting fittings with fluorescent lamps for moist and dusty rooms

In low dusty and moist rooms lighting fittings are used which meet the more complicated requirements by special construction or use of special materials.

Lighting fittings for dusty rooms mostly have a triangular basic body on the inclined external surfaces of which larger quantities of dust cannot deposit. The internal space of the lighting fitting is protected against dust mainly by rubber packings, the fluorescent lamps by dust-proof lamp sockets and perhaps additionally by protective tubings.

With other versions of construction, the entire internal space of a lighting fitting including the lamps is sealed by a glass window or boat.

The protective system of IP 5x, protection against detrimental deposition of dust inside a lighting fitting, will be sufficient in nearly every case.

Lighting fittings for moist rooms have no definite form of construction. Purely and simply it is important that the external materials are sufficiently resistant to the effects of moisture or aggressive vapour and that the inside materials - especially the electric parts of an illuminator - are protected against moisture by sealings.

The constructive elements mainly consist of plastic material or steel sheet with a special surface treatment. The internal parts are protected by rubber sealings and the fluorescent lamps by moisture-proof sockets and, if needed, by protective tubings additionally. In most of the cases, the protective system IP x4 - protection against detrimental effects of splash from any direction - is sufficient.

Like the combination illuminators, the moisture-proof lighting fittings, too, have a wide range of application due to their various types of fixing in the forms of ceiling mounting or pendant fittings and the possibilities of single or Christmas-tree pattern arrangement as well as by various accessories, for instance reflectors.

In order to facilitate the installation, assembly and maintenance of the lighting fittings, carrier rails are used for the installation of moisture-proof illuminators. The constructive solution of one certain protective system - protection against dust or moisture - nearly always involves the realization of both protective systems. In so far it is understandable that, for example, the most commonly used moisture-proof lighting fittings meet the requirements of dust protection, too.

For very wet rooms, waterproof illuminators are used the fluorescent lamps and electrical components of which are protected against the detrimental effects of water in the case of flooding in constant pressure and temporal conditions. These lamps are used especially in laundries, dairies, etc.

Narrow angle lighting fittings

For high rooms lighting fittings are required which have a great concentration of luminous flux and light intensity in the lower half of the room. Several narrow angle lighting fittings with various reflection materials meet these requirements, if economical discharge lamps are used.

Narrow angle lighting fittings with mirror reflector are used in rooms of more than 7 m in height.


Figure 48. Narrow-angle lighting fitting for illuminating halls with light distribution curve with a light output ratio of 0.66 (halogen metal vapour lamp NC 2000-60)

The different types of equipment - high-pressure mercury vapour lamps, halogen metal vapour lamps and high-pressure sodium vapour lamps - allow a wide-range application in all branches of industry. With the help of focussing mechanisms or different reflectors various forms of light distribution can be achieved.

Thus, quite a number of requirements as to lighting engineering can be met by the mentioned illuminators.

A still greater concentration per spot of light and two-phase switching can be realized by so called narrow angle twin lighting fittings. The open version of the two above mentioned narrow angle lighting fittings can be used in dry rooms, the glass-covered reflectors may also be used in rooms exposed to dust and moisture.

In addition to the above mentioned narrow angle lighting fittings there are those with a larger diameter for high-pressure mercury vapour lamps of 2000 watt or halogen metal vapour lamps of 2000 watt. As a result of suitable reflector forms and surface treatment, these illuminators have a great concentration of luminous intensity and therefore are suited to illuminate high rooms.

Narrow angle lighting fittings with enamel reflectors, due to the technical qualities - of the reflector surface - have an almost cosinusoidally radiating distribution of luminous intensity. They are mainly equipped with high-pressure mercury vapour lamps and are very well suited to evenly illuminate rooms of a medium height.

An adjustment of the lamp sockets for altering the shape of the light distribution is not practised with these illuminators, because this would not be efficient due to the size of the light-emitting surfaces of the high-pressure mercury vapour lamps and their size relation to the reflector as well as its surface reflection.

Fluorescent lamp narrow angle lighting fittings which are equipped with a number of fluorescent lamps in order to achieve a great concentration of the luminous flux show a cosinusoidal light distribution curve. Their utility consists in the illumination of high rooms with a relatively good vertical illumination and a good light colour. In addition, the great number of lamps per spot of light enables three-phase switching which avoids flickering.

Wall and ceiling fittings

In some service-rooms of industrial and social buildings porcelain fittings with glass balls are equipped with filament lamps.

Although such illuminators do not work very economically, they still have their right to exist, if the utilization of the mentioned rooms is considered. They are offered mainly as ceiling and wall fittings for the illumination of dry rooms or rooms exposed to moisture. They give scattered light, that is to say the light is almost equally distributed over all boundary surfaces of the room.

8.4.1.2. Local Lamps

Working places can be lighted in different ways and by lighting fittings for various purposes.

In practice, it is distinguished between three types of lighting systems each of which includes special lighting fittings:

- Working place orientated general lighting by lighting fittings for purposes of general lighting
- Working place lighting by lighting fittings for general lighting
- Working place lighting by fittings for local lamps.

All the three lighting systems have to illuminate working places of a limited extent, which requires of the lighting fittings a great concentration of the luminous flux in the lower half of the room.

This is to say that lighting fittings are used the light distribution of which is a direct or mainly direct one and which have a narrow-angle and cosinusoidally radiating concentrated light distribution. Lighting fittings for the lighting systems 1 and 2 have already been described.

The lighting-technical values achieved are only a question of the arrangement.

For the lighting system 3 special lighting fittings are required which are fixed directly on the working place near the object to be focussed. Thus, a great illumination on a comparatively small area and good shadow conditions are achieved.

For these lighting tasks the manufacturers of lighting fittings offer adjustable local lamps equipped with filament lamps or with fluorescent lamps. Starting from the same basic components, various and very different light distributions can be realized by attaching different reflectors. In addition, there are many ways of fixing the illuminators in the form of a variety of foot constructions for all double- and single-bracket joint fittings. This enables universal application. The lighting fitings can be categorized as follows:

- Double-bracket joint fittings for filament lamps or fluorescent lamps with a long working range resulting from the two tube brackets. With the help of them any area of a relatively large working surface can be lighted. In addition to the application on or at horizontal placing or mounting surfaces and on vertical mounting surfaces, special application to drawing machines is provided for.

- Single-bracket joint fittings for filament lamps or fluorescent lamps - only in the form of ceiling fittings - with short working ranges; these are mainly used as lighting fittings for machines due to their small dimensions.

- Another group of adjustable local fittings are the extending fittings for filament lamps and fluorescent lamps. They are used mainly on vertical walls and, in general, serve for lighting horizontal working surfaces in industry such as work benches and in social buildings, e.g. in offices. In stretched condition, these fittings have a long working range which is of decisive importance for the universal application of the fittings.

In addition to the above mentioned lighting fittings with lamps of 220 V, single-bracket fittings with low-voltage lamps are used. Due to their lamps and a corresponding form of reflectors, these lighting fittings have a great light intensity concentration and a narrow radiant angle.

Therefore, they are especially suitable for lighting small areas with great illumination values. The transformers required for operating these lighting fittings are placed in the foot of local table fittings or separately (with machine lighting fittings).

Besindes the adjustable local lamps, there are stationary lighting fittings for a number of special working places, for example machine lighting fittings at boring mills, sewing machines and others, for other working places, portable lamps with handle, connection line and plug are available for mobile use.

8.4.1.3. Flameproof and Explosion-proof Lighting Fittings

The above described technical fittings for indoor installations cannot be used in mines or production and store rooms where there is the risk of fire-damp or explosion without additional and special measures. For these purposes, special lighting fittings are required which are named flameproof fittings and explosion-proof fittings. If both requirements are met, the term is flameproof and explosion-proof fittings. In the course of technical development, lighting fittings protected in the described way are required in some branches of industry, e.g. chemical industry, for certain technological processes. With these lighting fittings it must be guaranteed that no explosive mixtures are ignited in case of operation-dependant contact sparking or heating up of the lighting fittings.

These fittings are constructed in such way that contact making is totally enclosed, electric connections are protected against coming loose and possible heating up remains in the permissible limits. In addition, special sealings are used and the fittings are marked as to their protective systems, ignition groups and explosion classes. This is made by letters and figures which are attached to the designation of the respective lighting fittings. Their meaning is:

Protective system

To the construction of flameproof and explosion proof lighting fittings, according to their respective purpose and serviceability, the protective systems mentioned in Table 28 can be applied.

Table 28. Protective systems of lighting fittings protected against fire-damp and explosion

Protective system

Characteristic

Pressure-resistant encapsulation

d

Increased safety

e

Oil encapsulation

o

Separate ventilation

f

Foreign air overpressure

f

Inherent safety

i

Special protection

s

Sand encapsulation

q

Particle ignition breakdown protection

dz

Ignition group

Inflammable gas and vapours are categorized by ignition groups according to their ignition temperature (with fluids also with view to their flash point).

Table 29. Ignition groups of lighting fittings protected against fire-damp and explosion

Designation of the ignition group

Ignition temperature in centigrade

T 1

> 450

T 2

> 300...450

T 3

> 200...300

T 4

> 135...200

T 5

> 100...135

T 6

> 85...100

Explosion class

The categorization of inflammable gas and vapours in explosion classes is determined by the explosion pressure generated by the explosion and the ignition penetration. There are the explosion classes I IIA, IIB, IIC. The class IIC is subdivided into IICa and IICb, according to the existing gas and air mixture.

In the construction of flameproof and explosion-proof lighting fittings different construction principles are followed according to the desired field of application. Explosion-proof fittings for fluorescent lamps are known which by a uniform light distribution create good lighting values in a room and which are especially suitable for general lighting. For direct working place lighting and for rooms which are much exposed to dust explosion-proof littings with reflectors and equipment with fluorescent lamps are more recommendable.

For safety reasons, the lighting fittings are operated by single-pin fluorescent lamps (with ignition strip) without starter. Special series reactors are required. They are integrated in the lighting fittings.

Table 30. Categorization of gases and vapours in explosion classes and ignition groups

Expl. class

Categorization of the gases in ignition groups


T 1

T 2

T 3

T 4

T 5

I

methane fire
damp





II A

ethane
propane
ammonia
toluene
acetone
benzol (pure)
carbon monoxide

ethyl acetate
n-butene
n-butyl
alcohol

gasoline
n-hexane



II B

ethylene
town gas

ethyl
alcohol

acet-aldehyde
diathyl ether



II Ca

water gas
hydrogen




carbon
disulphide

II Cb

acetylene





II C

all gases of the explosion classes II Ca and II Cb

Another way to illuminate rooms exposed to the risk of explosion consists in the use of lighting fittings for filament lamps or high-pressure mercury vapour lamps. However, with the latter equipment a series reactor must be used which - being accommodated in a separate enclosure - can be combined with the lighting fitting.

All lighting fittings of this kind must be tested by an authorized testing department.

8.4.2. Outdoor-Lighting Fittings

8.4.2.1. Street Lighting Lanterns

The increasing density of traffic in the streets and the greater risks of accidents resulting therefrom in the dark but also the higher cultural level in the cities and communities call for a street lighting of a high technical standard. The same demands are made on the lighting fittings because they are the most important parts in directing and transmitting the lamp-generated light. In addition to their technical function, the street lighting lanterns have to fulfill an aesthetical task; street lighting cort correspond to the modern character of cities and communities not only in the technical respect but also in design.

For lighting streets, squares and ways street lights fixed to a post or wall by a bracket, suspended street lights and street lights fixed on top of a lamp-post are used according to the technical, constructional and aesthetical requirements. In nearly all cases, high-pressure mercury vapour lamps, halogen metal vapour lamps and high-pressure sodium vapour lamps are used.

Bracket-fixed lights may be open or enclosed.

Depending on the place and degree of air contamination one of the mentioned types may be more economical than the other.

Both versions are, in general, equipped with an optical system, mostly in the form of a bidirectional mirror. This reflecting system serves to transform the luminous flux generated by the lamps into certain directions, i.e. to shape a certain light distribution. In favour of a good luminance distribution on the road surface, the light distribution solid is shaped in such way that the largest-possible portion of the emitted luminous flux reaches the road - longish form of the solid of light distribution - and the maximum light intensities are within an angle range of 60 to 65 degrees (LVK, spread beam).

Bracket-fixed lights are attached to buildings directly or to poles by side arms.

It has proved good if the lights are fixed at an angle of 15 degrees upwards from the horizontal line.


Figure 49. Brace-fixed lamp hole fitting with light distribution curve with a light output ratio of 0.76 (high-pressure mercury vapour lamp NF 400-01)

In addition to these high-grade lights with reflector systems there are more simple versions, especially for lighting ways.

These are lamp-post lights, fixed by brackets and equipped with simple reflectors such as enamel reflectors, aluminium reflectors and others as well as with mainly high-pressure mercury vapour lamps up to 125 W. They have rotational-symmetrical light distributions. With some types, also high-pressure mercury vapour lamps with internal reflector 80 and 125 W are used.

All bracket-fixed lights have built-in ballasts, compensation condensers and other electric components.

Suspended lights with bidimensional reflectors are - as to their optical system - similar to the bracket-fixed lights and meet the same requirements of lighting engineering. They are fixed by a suspension device on overvoltage wires or ropes over carriage-ways and pavements. Today, they are used only in places where the trafic ways are very narrow and no posts or other facilities for installing bracket-fixed lights can be erected. Besides the suspended lights mentioned there are those of less technical quality. Mostly they have a reflector of very dense opal glass or enamelled steel sheet. They are used mainly in industry or for lighting paths in smaller communities.

Lights fixed on top of a lamp-post in various designs and for equipment with high-pressure mercury vapour lamps are used mostly in living areas for lighting streets and ways. In addition to their technical function of lighting the surface of the street they have an aesthetical task to fulfill. A portion of the light generated by the lamps is emitted horizontally or in the upper half-space. This brights up buildings, trees, monuments and other things of larger size, so that living areas look more lively in the dark. In addition, a rather good luminance distribution is achieved on the street surface. However, a disadvantage consists in the angle range of 80 to 90 degrees (not shielded). For this reason, lights on lamp-posts are not installed in roads and streets of a great density of traffic.


Figure 50. Brace-fixed lamp pole fitting with light distribution curve with a light output ratio of 0.73 (NA 400-01 sodium vapour lamp)

8.4.2.2. Decorative Outdoor-Lighting Fittings

For a number of outdoor-lighting installations, for instance in parks, on lawns, pleasure-grounds, sports fields, gardens and at building entrances lighting fittings are necessary which have to meet great decorative requirements in addition to mere illumination. In the dark and by day as well they shall contribute to the architectural aspect.

We distinguish with this type of fittings those for lamp-posts of 2 to 3 m in height, (fitting on top of the lamp-post), pillar ligths, e.g. for gateways, outdoor-lighting fittings to be fixed on walls, ceiling fittings, e.g. for doorways, edged glass fittings to be fixed on walls and flower-bed lights.

All the above mentioned lighting fittings are available in various forms according to the conditions of use, the design, the way of fixing and the material used.

All versions are suited mainly for filament lamp equipment. Very often, technical parameters, especially the glare protection angle, are subordinated to decorative considerations.

8.4.2.3. Floodlights and Spotlights

For lighting large outdoor surfaces, especially in industry and with sports fields, where it is not possible to erect many individual lamp-posts for top lights or bracket-fixed lights, lighting columns must be erected. In order to meet the requirements of illumination, which in such places are usually very great, the columns are equipped with lighting fittings of a high concentration of luminous intensity and a narrow half-scattering angle or of lower luminous intensity but wide spreading. These values can be put into practice by floodlights. Basically, it is distinguished between two constructional versions:

- Lights with rotational-symmetrical luminous intensity
- Lights with symmetrical luminous intensity.

Both types can be manufactured in various sizes and, depending on their construction, are suited for equipment with high-pressure mercury vapour lamps, halogen metal vapour lamps, high-pressure natrium vapour lamps, halogen filament lamps and general purpose filament lamps.


Figure 51. Small floodlight with light distribution curve (halogen metal vapour lamp HFL 1000)

1 concentration, 2 scattering


Figure 52. Industrial spot-light with light distribution curve (high-pressure mercury vapour lamp NF 400-01)


Figure 53. Mirror downlighter with light distribution curves (general service lamp 300/500 W curve around 0 degree)

Efficiency factor of the fitting:

1 concentration = 0.62

2 scattering = 0.66 (high-pressure mercury vapour lamp NF 400-01; curve around 60 degree)

Efficiency factor of the fitting:

1 concentration = 0.62
2 scattering = 0.73

It presents itself to achieve various forms of light distribution curves by one lighting fitting by using reflectors of different sizes and shapes, by surface treatment of the reflectors and by using focussing devices - especially with rotational-symmetrical lighting fittings. The series of such lighting fittings prove that this can be done. By a relatively small range of types of floodlights in moisture-proof construction, all tasks of floodlight illumination can be solved.

In addition to floodlight, beam projectors for outdoor-lighting are also used for lighting up buildings, monuments and other things. Such devices are called spotlights - they are very similar to floodlights. Besides the creation of a certain illumination, with these lighting installations it is a question of maintaining the right light colour, shading and evenness on the object to be spotlighted. All these parameters, however, do not immediately influence the construction of the lighting fittings. What is important, is to use the right lamp in the right place.

A principle assignment of individual lighting fittings to certain definite lighting tasks cannot be given. All floodlights and spotlights are mostly equipped with a surface-refined aluminium reflector and with a closing glass pane.

For adjusting the horizontal and vertical swinging angle - especially with flood lights - some floodlights or spotlights are equipped with horizontal rotation devices and [...] vertical adjustment.

Floodlights mostly supply rather exactly directed light. Manufacturers often indicate the light distributions in Cartesian coordinates or in tables. For technical calculations, the degree of efficiency of a fitting and the bundle angle (half-scattering angle and tenth-scattering angle) are important.

8.4.3. Lighting Fittings for Representation Purposes and Housing Space

In opposite to utility lighting fittings the light of which, above all, has to fulfill certain technical functions such as illumination, luminance, glare protection, evenness, shading and others, with the lighting of rooms for representation purposes such as restaurants, theatres, cinemas, cultural establishments, hotels etc. aesthetical tasks predominate. In these establishments meant for diversion and recovery light and thus the lighting fittings nearly always are included in the interior design of the entire room. This explains that the form of the fittings and the light colour are of decisive importance, the technical parameters such as light distribution of course being taken into consideration, too. In contrast to this, questions of luminance distribution, glare and evenness are not always of so great an importance. They may even be used to create special effects.

Lighting fittings for representation purposes comprise a wide range of fittings manufactured either as single pieces or in series. This range consists of built-in ceiling fittings or ceiling fittings, suspended or pendant fittings, wall fittings as well as standard lamps. From single-lamp fittings to large chandelier or similar suspended fittings, the lighting fittings are equipped with various reflection and transmittion materials.

The range of lamps is equally diverse - from filament lamps to various types of discharge lamps. It seems to be rather difficult to select one or another fitting of this range and describe it as a representative. In their technical structure the fittings for representation purposes as well as the utility fittings must meet the relevant standards. In housing space too, light has - unlike mere utility lighting - an aesthetical task to fulfill by contributing to a comfortable atmosphere in the room. In this context, a flat must be divided up in two parts:

- Working area (kitchen and bathroom)
- Recreation area (sitting-room, nursery, bedroom).

In the working area definits technical characteristic values of lighting are required. The fittings offered for this purpose are increasingly equipped with fluorescent lamps. Open as well as closed types are used. With the help of such fittings relatively great illuminations with good evenness and little glare can be achieved.

In the recreation area mainly fittings for filament lamps are used. Various ceiling, suspended, wall and standard fittings are covered by glass, plastic or textile lamp-screens, so that their light helps to create a comfortable atmosphere in the room.

This means that individual zones of the room require different lighting, i.e. greater contrast is desired. Domestic lighting fittings, especially for the recreation area, are very much subject to the trend of fashion; they are constantly harmonized with the design of the rest of furniture and interior architecture.

In order to guarantee the technical quality of lighting and to prevent the waste of energy domestic lighting fittings are tested as to certain minimum requirements in the field of their technical parameters some values being internationally recommended.

These are

- An efficiency of the lighting fitting equal to or exceeding 50 %
- Observance of recommended glare protection angles
- Observance of recommended luminance values
- Compliance with illumination values with local lamps.

8.4.4. Lighting Fittings for Special Purposes

This term unites all lighting fittings that serve the above mentioned purposes. They include decorative lighting fittings for advertisement, illumination, theatre, film and television.

Medical purposes, research and teaching require special fittings, too.

By the term “special” a special mechanical version, special light source or special optical equipment of a lighting fitting is understood.

However, it is beyond the scope of the present textbook to deal with this group of lighting fittings.

Questions for repetition and knowledge tests

1. What are the tasks of lighting fittings in a lighting installation?
2. What kinds of lighting fittings are known?
3. What requirements must a local lamp (working place, lighting fitting) meet?

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