AALTO UNIVERSITY

SCHOOL OF SCIENCE AND TECHNOLOGY

Faculty of Electronics, Telecommunications and Automation Department of Electronics Lighting Unit Matti Sinisalo Standardisation of LED luminaires and controlgear for safety and performance S-118.4250 Postgraduate seminar on illuminating engineering 2010 Seminar work Espoo 2010-12-01 Supervisor Professor Liisa Halonen

AALTO-UNIVERSITY

SCHOOL OF SCIENCE AND TECHNOLOGY Abstract of Seminar Work

Author: Matti Sinisalo Name of the work: Standardisation of LED luminaires and controlgear for safety and performance Date: 2010-12-01

Number of pages: 24 pages

Faculty: Faculty of electronics, communication and automation, Department of electronics Professorship: S-118

Supervisor: Liisa Halonen Abstract text: Light emitting diodes (LEDs) are seen an important technology to improve energy efficiency in lighting. The efficacy and quality of LEDs are developing fast. While there are thousands of products available on markets, their quality and performance are not presented in clearly comparable manner. The lack of standardisation has been commonly mentioned as a disadvantage of using LEDs. To allow greater acceptance to LEDs, it is clear that in near future appropriate standards are necessary to be developed. In this seminar paper, the current status of international standardisation of LED luminaires and controlgear is reviewed. Both safety and performance standardisation is taken into consideration. Keywords: LED, controlgear, luminaire, standard

Preface

The Lighting Unit of Aalto University’s School of science and technology organised the seminar on energy efficient LED lighting on 9–10 September 2010. Lecturers were from Finland, the USA and Germany representing universities and the lighting industry. Lecture topics covered LED lighting solutions for outdoor lighting, LED testing and standardisation, optical, thermal and colour issues of LEDs and current technological status and future development in LED lighting. By writing this seminar work, my goal is to share information to my fellow students about current status of standardisation of LED luminaires and controlgear. I would especially like to thank Mr. Markku Norhio representing Helvar from all valuable information he gave to me. I would also like to thank all lecturers, organisers and participants of this informative and succeeded seminar.

Espoo 2010-12-01

Matti Sinisalo

Table of Contents

 

Preface ...............................................................................................................................3  

List of symbols and abbreviations.....................................................................................5  

1.   Introduction ...............................................................................................................6  

2.   LED product standardisation.....................................................................................7  

3.   Safety requirements and tests for controlgear for LED modules ..............................9  

4.   Performance requirements and tests for controlgear for LED modules ..................19  

Conclusions .....................................................................................................................23  

References .......................................................................................................................24  

List of symbols and abbreviations

LED light emitting diode IEC International Electrotechnical Commission PAS publicly available specification SELV safety extra low voltage IEV International Electrotechnical Vocabulary tc rated maximum operating temperature of the case

of a controlgear r.m.s. root-mean-square t temperature d.c. direct current a.c. alternating current λ power factor tl maximum surface temperature (t-lifetime) of the

controlgear that allows a life of 50 000 h to achieved

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1. Introduction

Light emitting diodes (LEDs) are seen an important technology to improve energy efficiency in lighting. The efficacy and quality of LED are developing fast. With LEDs it is possible to realise many different kind of lighting needs; LEDs are highly effective illuminants for work and reading luminaires, orientation aids, pathway lighting, emergency lighting, decorative and architectural purposes and accent applications (Pfanner, 2004). Nowadays, also for general lighting purposes in commercial, industrial and residential facilities and outdoors, LEDs provide competitive solutions. While there are thousands of products available on markets, their quality and performance are not presented in clearly comparable manner. This deviation in quality and performance is even greater in LED luminaires, since, for example, installation method, ambient temperature and voltage variations affect the output of LEDs.

The lack of standardisation has been commonly mentioned as a disadvantage of using LEDs (Halonen et al. 2010). To allow greater acceptance to LEDs, it is clear that in near future appropriate standards are necessary to be developed (Ludwig 2010). In this seminar paper, the current status of international standardisation of LED luminaires and controlgear published by IEC is reviewed. Both safety and performance standardisation is taken into consideration. The electromagnetic compatibility of LED luminaires and controlgear is not discussed in this paper. Mainly this paper deals with the standardisation of LED controlgear, since especially for LED luminaires there are only a few safety requirements and performance requirements are not published.

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2. LED product standardisation

LED product standards can be divided into safety and performance requirements. In general, the standardisation is further in safety than in performance requirements. The safety and performance requirements for LED luminaires and controlgear are listed in Table 1. For luminaires, IEC 60598-1 is the most important standard, since it gives all the general requirements for safety. Particular requirements, for example for recessed luminaires (IEC 60598-2-2), luminaires for emergency lighting (IEC 60598-2-22) or floodlights (IEC 60598-2-5), are expressed in IEC 60598-2 series. There is not performance standard for luminaires but for LED luminaires the standardisation is in progress by IEC (Norhio, 2010). For controlgear both safety and performance standards are already published. LED controlgear must meet the general requirements given in IEC 61347-1 and, in addition, particular requirements given IEC 61347-2-13. The performance requirements for controlgear for LED modules are given in IEC 62384 and its amendment 1.

Table 1. The overview of IEC standards for LED luminaires and controlgear (CELMA 2010).

Product type Safety standard Performance standard LED luminaires 60598-1

60598-2 series PAS XXXXX

LED controlgear 61347-1 61347-2-13

62384

As shown in Figure 1, LED products are divided into three groups: Self-ballasted LED lamps, electronic controlgear for LED modules and self-ballasted LED modules. Controlgear can, with suitable connection system, form an illuminant system with LED modules.

Figure 1. Overview of systems composed of LED modules and controlgear (IEC 62031, 2008).

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Self-ballasted LED modules are designed to for connection to the supply voltage. However, if the self-ballasted LED module is equipped with a lamp cap, it is regarded to be a self-ballasted LED lamp (IEC 62031). The unit that is inserted between the supply and LED modules, which serves to supply the LED modules with their rated voltage or rated current, is defined as the electronic controlgear for LED modules (IEC 61347-2-13). The controlgear may include means for dimming, correcting the power factor and suppressing radio interference.

LED modules are classified, according to the method of installation, as built-in, integral and independent modules. If a self-ballasted LED module, an electronic controlgear for LED module or their combination are regarded as a built-in component, it means that it is designed to form a replaceable part built into a luminaire and it is not intended to be mounted outside a luminaire. If they are regarded as an integral component, it means that they are generally designed to form a non-replaceable part of a luminaire. Independent components are designed so that they can be mounted or placed separately from a luminaire and they provide all the necessary protection with regard to safety (IEC 62031).

Controlgear are classified, according to the method of installation, as built-in, independent or integral. An example of each controlgear class is presented in Figure 2. Built-in controlgear are generally designed to be built into a luminaire, a box, an enclosure or the like and not intended to be mounted outside a luminaire. Independent controlgear consists of one or more separate elements so designed that it can be mounted separately outside a luminaire, with protection according to the marking of the controlgear and without any additional enclosure. Integral controlgear forms a non-replaceable part of a luminaire and it cannot be tested separately from the luminaire (IEC 61347-1). Sometimes term ballast is used as byword for controlgear but according to IEC 61347-1 it means unit that is inserted between the supply and one or more discharge lamps which by means of inductance, capacitance, or a combination of both, serves mainly to limit the current of the lamp to the required value. That is why ballast should not be used in place for controlgear for LED modules. Controlgear are also classified according to protection against electric shock, as SELV-equivalent or isolating controlgear, auto-wound controlgear and independent SELV controlgear (IEC 61347-2-13).

Figure 2. A built-in (a), an independent (b) and an integral (c) controlgear (Tridonic, 2010; 2009; 2008a).

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3. Safety requirements and tests for controlgear for LED modules

An overview of safety requirements and tests are presented in Figure 3. Controlgear shall be so designed and constructed that in normal use it operates without danger to the user or surroundings. Compliance is checked by carrying all the tests specified in IEC 61347-1, IEC 61347-2-13 and, if applicable, in IEC 60598-1 and IEC 60065.

Figure 3. The overview of safety requirements of and tests for controlgear for LEDs.

Particular safety requirements for controlgear for LED modules state that following items must be marked either on the controlgear or made available in the manufacturer’s catalogue. The mark of origin of product (trade mark, manufacturer’s name or name of the responsible vendor/supplier) and model number must be presented. If controlgear is classified as independent, it must be presented with an appropriate symbol (Figure 4f).

Figure 4. Marking symbols for controlgear (IEC 61347-1).

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The correlation between replaceable and interchangeable parts, including fuses, of controlgear shall be marked unambiguously by legends on the controlgear or be specified in manufacturer’s catalogue.

If the controlgear has earthing terminals, they shall be identified by the appropriate symbol. Symbol presented in Figure 4a describes a terminal to which are connected parts connected to earth for safety reasons. Symbol presented in Figure 4b describes a terminal to which are connected parts which may be necessary to connect to earth for reasons other than safety. A terminal whose potential is taken as reference is presented in Figure 4c. The earthing terminal marking symbols shall not be placed on screws or other easily removable parts. The earthing symbols presented in IEC 61347-1 may be, however, slightly misleading since International Electrotechnical Vocabulary (IEV) chapter 195 (Earthing and protection against electric shock) recognises only two kinds of earthing: protective earthing (195-01-11) and functional earthing (195-01-13) (IEV, 2010). That is why it is not clear why there should be needs for any other symbols for marking earthing terminals.

Symbol presented in Figure 4e is for temperature declared, thermally protected controlgear. The dots in the triangle shall be replaced by the value of the rated maximum case temperature in degrees Celsius assigned by the manufacturer. The controlgear case temperature at any place shall not exceed the marked value (IEC 61347-1). The F mark (Figure 4d) requirement has been removed from the latest edition of IEC 60598-1. It assumed that all products have to comply with mounting on normally flammable surfaces. If a product cannot meet this requirement, then it shall be marked accordingly.

Wiring diagram must indicate the position and purpose of terminals. In the case of lamp controlgear having no terminals, a clear indication shall be given on the wiring diagram of the significance of the code used for connecting wires (for example colours). Controlgear that operates in specific circuits only shall be identified accordingly, for example by marking or wiring diagram. The value of tc (rated maximum temperature on the outer surface) must be indicated and if it relates to a certain place on the controlgear, this place shall be indicated or shall be specified in the manufacturer’s catalogue (Figure 5). Rated supply voltage (or voltages, if there are several), voltage range and supply frequency must be marked on controlgear. Supply current, however, may be given in the manufacturer’s literature. For constant voltage types the rated output voltage and for constant current types the output current together with maximum output voltage must be presented. If the controlgear is suitable for operation with LED modules only, it must be indicated (IEC 61347-1; IEC 61347-2-13).

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Figure 5. Tc point indication on controlgear (Tridonic, 2008b).

In addition to above mandatory markings, if applicable, a mention whether the controlgear has mains-connected windings or whether controlgear is SELV-equivalent must be presented. An indication that the controlgear does not rely on the luminaire enclosure for protection against accidental contact with live parts shall be made. Suitable conductor cross-sections for terminals, if any, shall be given. Also, if applicable, LED module type and rated wattage or wattage range for which the controlgear is suitable shall be made available (IEC 61347-1; IEC 61347-2-13).

Durability and legibility of marking

The durability and legibility of markings must be checked by inspection and by trying to remove the marking by rubbing lightly, for 15 s each time, with two pieces of cloth, one soaked with water and the other with petroleum spirit. Markings shall be durable after the test. (IEC 61347-1)

Protection against accidental contact with live parts

Controlgear, which do not rely upon the luminaire enclosure for protection against electric shock, must be sufficiently protected against accidental contact with live parts when installed in normal use. Integral lamp controlgear, which relies upon the luminaire enclosure for protection, shall be tested according to its intended use. Parts providing protection against accidental contact shall have adequate mechanical strength and shall not work loose in normal use. It shall not be possible to remove them without the use of a tool. Lamp controlgear incorporating capacitors of total capacitance exceeding 0,5 µF shall be constructed so that the voltage at the lamp controlgear terminations does not exceed 50 V, 1 min after disconnection of the lamp controlgear from a source of supply at rated voltage. Compliance is checked by inspection and by a manual test, and with regard to protection against accidental contact, by means of the test finger using an electrical indicator to show contact. (IEC 61347-1)

For SELV-equivalent controlgear, the accessible parts shall be insulated from live parts by double or reinforced insulation. Output circuits of SELV- or SELV-equivalent controlgear may have exposed terminals, if the rated output voltage for constant voltage

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controlgear or maximum output voltage for constant current controlgear under no load does not exceed 25 V r.m.s. and if the no-load output voltage does not exceed 33 V r.m.s. and the peak does not exceed 33√2 V. Compliance is checked by measuring the output voltage when steady conditions are established, the controlgear being connected to rated supply voltage and rated frequency. For the test under load, the controlgear is loaded with a resistance, which would give rated output at rated output voltage. For controlgear with more than one rated supply voltage, the requirement is applicable for each of the rated supply voltages. Controlgear with a rated output voltage above 25 V shall have insulated terminals. (IEC 61347-2-13)

Terminals

Altogether, seven types of terminals are defined in IEC 60598-1: pillar, screw, stud, saddle, lug, mantle and screwless terminals. Requirements presented in this standard, however, do not exclude terminals of types other than defined. Terminals shall provide adequate connection of the conductors and shall withstand the mechanical, electrical and thermal stresses occurring in normal use. Compliance is checked by mechanical, and electrical tests.

Resistance to corrosion is checked by the corrosion test. Terminals shall be fixed. When tightened or loosened, or when conductors are inserted or withdrawn, the terminals shall not work loose, internal wiring shall not be subjected to stress, and creepage distances and clearances shall not be reduced. Compliance is checked by inspection, by measurement and by testing. Terminals shall clamp the conductor reliably between metal surfaces. Compliance is checked by inspection and by pulling test. During the test, the conductor shall not move noticeably in the terminal. Terminals shall clamp the conductor without undue damage to the conductor. Conductor are unduly damaged if the show deep or sharp indentations. (IEC 60598-1)

Provision for protective earthing

Earthing terminals have the same requirements that all the terminals have. The electrical connection shall be adequately locked against loosening, and shall not be possible to loosen the electrical connection by hand without the use of a tool. For screwless terminals, it shall not be possible to loosen the electrical connection unintentionally. Earthing of lamp controlgear (other than independent lamp controlgear) via means of fixing the lamp controlgear to the earthed metal is permitted. However, if a lamp controlgear has an earthing terminal, this terminal shall only be used for earthing the lamp controlgear. All parts of an earthing terminal shall be such as to minimize the danger of electrolytic corrosion resulting from contact with the earth conductor or any other metal in contact with them. The screw and the other parts of the earthing terminal shall be made of brass or other metal no less resistant to corrosion, or material with a non-rusting or any other metal in contact with them. Compliance is checked by inspection, by manual test and by mechanical and electrical test that are required for terminals. (IEC 61347-1)

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Moisture resistance and insulation

Lamp controlgear shall be moisture-resistant. They shall not show any appreciable damage after being subjected to the following test. The lamp controlgear is placed in the most unfavourable position of normal use, in a humidity cabinet containing air with a relative humidity maintained between 91% and 95%. The temperature of the air at all places where samples can be located shall be maintained within 1 ºC of any convenient value t between 20 ºC and 30 ºC. Before being placed in the humidity cabinet, the sample is brought to a temperature between t and (t+4) ºC. The sample shall be kept in the cabinet for 48 h. Before the insulation test, visible drops of water, if any, are removed by means of blotting paper. Immediately after the moisture treatment, the insulation resistance shall be measured with a d.c. voltage of approximately 500 V, 1 min after application of the voltage. Lamp controlgear having an insulating cover or envelope shall be wrapped with metal foil. Insulation resistance shall be not less than 2 MΩ for basic insulation. Insulation shall be adequate

- between live parts of different polarity which are or can be separated; - between live parts and external parts, including fixing screws; - between live parts and control terminals, where relevant.

In the case of lamp controlgear having an internal connection or component between one or more output terminals and the earth terminal, such a connection shall be removed during this test. (IEC 61347-1)

For SELV-equivalent controlgear, the insulation between input and output terminals not bonded together shall be adequate. With double or reinforced insulation, the resistance shall be not less than 4 MΩ. (IEC 61347-2-13)

Electric strength

Controlgear shall have adequate electric strength. Immediately after the measurement of insulation resistance, the controlgear shall withstand an electric strength test for 1 min applied between the parts specified. The test voltage of substantially sine-wave form, having a frequency of 50 Hz or 60 Hz shall correspond to the values in Table 2. Initially, not more than half the specified voltage shall be applied, the voltage then being raised rapidly to the prescribed value. (IEC 61347-1)

Table 2. Electric strength test voltage (IEC 61347-1).

Working voltage U Test Voltage V

Up to and including 42 V 500 Basic insulation 2U + 1000 Supplementary insulation 2U + 1750

Above 42 V up to and including 1 000 V

Double or reinforced insulation 4U + 2750

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Insulation conditions of windings of separating transformers in SELV-equivalent controlgear shall apply according to 14.3.2 of IEC 60065. (IEC 61347-2-13)

Fault conditions

Controlgear shall be so designed that, when operated under fault conditions, there shall be no emission of flames or molten material or production of flammable gases. The protection against accidental contact shall not be impaired. For lamp controlgear marked with symbol presented in Figure 4e, the case temperature at any place shall not exceed the marked value.

Operation under fault conditions denotes that each of the following conditions is applied in turn and, associated with it, those other fault conditions:

- Short circuit across creepage distances and clearances; - short-circuit across or, if applicable, interruption of semi-conductor devices; - short-circuit across insulation consisting of covering of lacquer, enamel or

textile; - short circuit across electrolytic capacitors.

Compliance is checked by operating the controlgear at any voltage between 90% to 110% of the rated supply voltage with the lamp connected and with the lamp controlgear case at tc; then, each of the fault conditions shall be applied in turn. Components such as resistors, capacitors, semiconductors, fuses, etc. may fail during fault conditions. It is permitted to replace such components so as to continue the test.

After the tests, when the lamp controlgear has returned to ambient temperature, the insulation resistance measured at approximately 500 V d.c. shall be not less than 1 MΩ.

To check whether gases liberated from component parts are flammable or not, a test with a high-frequency spark generator is made. Whether accessible parts have become live has to be checked by testing. To check whether emission of flames or molten material might present a safety hazard, the test specimen is wrapped with a tissue paper and shall not ignite.

Transformer heating

In SELV-equivalent controlgear, the windings of separating transformers shall be tested. During normal operation, no part of the apparatus shall attain an excessive temperature. Compliance is checked by measuring the temperature rise under normal operating conditions after 4 h of operation. When the apparatus is operated under fault conditions, no part shall reach such a temperature that there is a danger of fire to the surroundings of the apparatus and safety is impaired by abnormal heat developed in the apparatus. Compliance is checked by the tests.

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For normal operation, the values in the second column of Table 3 shall apply. For operation under abnormal conditions and fault conditions, the values in the third column of Table 3 shall apply.

Table 3. Permissible temperature rise of parts of the apparatus (IEC 60065).

Parts of the apparatus Normal operating conditions

K

Fault conditions

K

a) Accessible parts Knobs, handles, etc. if

- metallic 30 65 - non-metallic 50 65

Enclosures if - metallic 40 65 - non-metallic 60 65

b) Parts providing electrical insulation Supply cords and wiring insulation with

- PVC or synthetic rubber - not under mechanical stress 60 100 - under mechanical stress 45 100 - natural rubber 45 100

Other insulations of: - thermoplastic materials varies varies - non-impregnated paper 55 70 - non-impregnated cardboard 60 80 - impregnated cotton, silk, paper and textile 70 90 - laminates based on cellulose or textile, bonded with

- phenol-formaldehyde, melamine-formaldehyde, phenol-furfural or polyester

85 110

- epoxy 120 150 - mouldings of - phenol-formaldehyde or phenol-furfural, melamine and melamine phenolic compounds with

- cellulose fillers 100 130 - mineral fillers 110 150 - thermosetting polyester with mineral fillers 95 150 - alkyd with mineral fillers 95 150

- composite materials of - polyester with glass-fibre reinforcement 95 150 - epoxy with glass-fibre reinforcement 100 150 - silicone rubber 145 150

c) Parts acting as a support or a mechanical barrier including the inside of enclosures

Wood and wood-based materials 60 90

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Thermoplastic materials varies varies Other materials varies varies

d) Winding wires - insulated with

- non-impregnated silk, cotton, etc. 55 75 - impregnated silk, cotton, etc. 70 100 - oleoresinous materials 70 135 - polyvinyl-formaldehyde or polyurethane resins 85 150 - polyester resins 120 155 - polyesterimide resins 145 180

e) Other parts These temperature rises apply to parts not covered by items a), b) c) and d): Parts of wood and wood-based material 60 140 Lithium batteries 40 50 Resistors and parts of metal, glass, ceramic, etc. no limit no limit All other parts 200 300

Abnormal conditions

The controlgear shall not impair safety when operated under abnormal conditions. For controlgear, which are of the constant voltage or constant current output type, the following conditions shall be applied for 1 h:

a) No LED module is inserted b) Double the LED modules or equivalent load for which controlgear is

designed. c) The output terminals of the controlgear shall be short-circuited.

During and at the end of the tests specified, the controlgear shall show no defect impairing safety, nor shall any smoke or flammable gases be produced. In addition, for controlgear of constant current output type the maximum output voltage shall not be exceeded. Compliance shall be tested at any voltage between 90% and 110% of the rated supply voltage.

Construction

Wood, cotton, silk, paper and similar fibrous material shall not be used as insulation, unless impregnated. Compliance is checked by inspection. (IEC 61347-1)

Socket-outlets in the output circuit shall not accept plugs complying with IEC 60083 (plugs and socket-outlets for domestic and similar general use standardized in member countries of IEC) and IEC 60906 (IEC System of plugs and socket-outlets for household and similar purposes); neither shall it be possible to engage plugs accepted by socket-outlets in the output circuit with socket-outlets complying with IEC 60083 and IEC 60906. Compliance is checked by inspection and by manual test. (IEC 61347-2-13)

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Creepage distances and clearances

Creepage distances and clearances shall be not less than the values given in Table 4 and Table 5, as appropriate. The contribution to the creepage distance of any groove less than 1 mm wide shall be limited to its width.

Table 4. Minimum distances for a.c. (50/60 Hz) sinusoidal voltages (IEC 61347-1).

Working voltage not exceeding V (r.m.s.)

Minimum clearance mm 50 150 250 500 750 1 000 a) Between live parts of different polarity, and b) Between live parts and accessible metal parts

which are permanently fixed to the lamp controlgear, including screws or devices for fixing covers or fixing the lamp controlgear to its support

c) For ballasts declared not to rely on the luminaire enclosure for protection against electric shock – between live parts and the outer accessible surface of insulating parts

- Creepage distances Insulation PTI ≥ 600 0,6 1,4 1,7 3 4 5,5

< 600 1,2 1,6 2,5 5 8 10 - Clearances 0,2 1,4 1,7 3 4 5,5

c) Between live parts and a flat supporting surface or a loose metal cover, if any, if the construction does not ensure that the values under b) above are maintained under the most unfavourable circumstances

- Clearances 2 3,2 3,6 4,8 6 8

Table 5. Minimum distances for non-sinusoidal pulse voltages (IEC 61347-1).

Rated pulse voltage peak kV

2,0 2,5 3,0 4,0 5,0 6,0 8,0 10 12 15 20 25 30 40 50 60 80 100

Minimum clearance mm

1,0 1,5 2 3 4 5,5 8 11 14 18 25 33 40 60 75 90 130 170

Screws, current-carrying parts and connections

Screw, current-carrying parts and mechanical connections, the failure of which might cause the controlgear to become unsafe, shall withstand the mechanical stresses occurring in normal use. Requirements are the same as are required for luminaires. Compliance is checked by inspection and the tests of 4.11 and 4.12 of Clause 4 of IEC 60598-1. (IEC 61347-1)

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Resistance to heat, fire and tracking

Parts of insulating material either retaining live parts in position or providing protection against electric shock shall be sufficiently resistant to heat. Compliance is checked by the certain resistance-to-heat test in accordance with IEC 60598-1. External parts of insulating material providing protection against electric shock and parts of insulating material retaining live parts in position shall be sufficiently resistant to flame and ignition or fire. (IEC 61347-1)

For materials other than ceramic, compliance is checked by the test in which external parts of insulating material providing protection against electric shock shall be subjected for 30 s to the glow-wire test in accordance with IEC 60695-2-10 or by the in which parts of insulating material retaining live parts in position shall be subjected to the needle-flame test in accordance with IEC 60695-11-5, as appropriate. Controlgear intended for building into luminaires other than ordinary, independent controlgear, and controlgear having insulation subject to starting voltages with a peak value higher than 1500V shall be resistant to tracking. (IEC 61347-1)

Resistance to corrosion

Ferrous parts, the rusting of which might cause the lamp controlgear to become unsafe, shall be adequately protected against rusting. Compliance is checked by the following test:

All grease is removed from the parts to be tested. The parts are then immersed for 10 min in a 10% solution of ammonium chloride in water at a temperature of 20 °C ± 5 °C. Without drying, but after shaking off any drops, the parts are placed for 10 min in a box containing air saturated with moisture at a temperature of 20 °C ± 5 °C. After the parts have been dried for 10 min in a heating cabinet at a temperature of 100 °C ± 5 °C, their surfaces shall show no signs of rust. (IEC 60598-1)

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4. Performance requirements and tests for controlgear for LED modules

Performance requirements for d.c. (<250 V) or a.c. (<1000 V at 50/60 Hz) supplied electronic gear for LED modules (according to IEC 62031) are presented in IEC 62384 (2006) and its amendment 1 (2009). An overview of performance requirements and tests are presented in Figure 6. In performance criteria, there are presented controlgear classifications (Figure 7), product markings, the properties of output voltage and current, total circuit power, power factor, supply current, impedance at audio-frequencies, operational test and endurance.

Figure 6. The overview of performance requirements and tests of controlgear for LED modules.

Electronic controlgear for LED modules can be classified according to the load, the output voltage or the output current. If a controlgear is classified according to the load, this type of controlgear is designed either for use with one specific output wattage only (one or more LED modules) or for use with one or more LED modules with a total load within the declared wattage range. Furthermore, both voltage and current classified controlgear are divided into two subclasses depending whether their output voltage or current is stabilised or not.

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Figure 7. The classification of electronic controlgear for LED modules.

Marking

The circuit power factor has to given as, for example λ = 0.9 C. Letter C after power factor value must be marked if the power factor is less than 0.95 leading. In addition to this mandatory marking, if applicable, limits of permissible temperature range, an indication that the controlgear has a stabilised output voltage (or current), an indication that the controlgear is suitable for operation with a mains supply dimmer and an indication of the operation mode (e.g. phase control) must be given. These information must be given on the controlgear or made available in manufacturer’s catalogue, excluding power factor, which must be clearly be marked on controlgear. (IEC 62384)

Controlgear manufacturer can, naturally, present additional information on product. IEC 62384 recognises as optional markings total circuit power and, if applicable, the symbol

(indicating compliance with conditions for audio-frequency impedance) and the symbol indicating that the controlgear is a short circuit proof type.

Output voltage and current

For output voltage and current there are requirements for starting and connecting, normal operation, capacitive load and voltage surges during switching and operation. The output of controlgear, after starting or connecting, should be within 110% (if output voltage is a.c., the 110% is the percentage of the r.m.s. value) of its rated value within 2 s. Maximum current or maximum voltage shall not exceed the values given by the manufacture. When operating at rated supply voltage, the output must not differ by more than ±10% from the rated voltage of the LED modules, if a controlgear is classified according to non-stabilised output voltage. For a controlgear having stabilised output voltage, the output voltage must not differ more than ±10% from the rated voltage of the LED modules, when supplied at within the range of 92…106% of the rated supply voltage. Same criteria are presented for current during operation. If a controlgear is classified as multiple load controlgear, it shall be tested with both

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minimum and maximum load. Values for permissible voltage surges during switching and operation are under consideration. If the LED module contains capacitors, current pulses may be generated when connecting the LED module to the controlgear. This must neither disturb the proper functioning of overcurrent detection nor the starting process of the controlgear. (IEC 62384)

Total circuit power

At rated voltage, the total circuit power shall not be more than 110% of the value declared by the manufacturer, when the controlgear is operated with LED modules (IEC 62384).

Circuit power factor

The measured circuit power factor must not be less than marked by more than 0,05 when operating on rated wattage with LED module(s) and with rated supply voltage and frequency (IEC 62384).

Supply current

At rated voltage, the supply current must not differ by more than +10% from the value marked on the controlgear or declared in the manufacturer’s literature, when that controlgear is operated on its rated wattage with LED modules (IEC 62384).

Impedance at audio-frequencies

For every signal frequency between 400 Hz and 2000 Hz, the impedance of the controlgear when operated with the rated LED module load at rated voltage and frequency shall be inductive in characteristic. Its impedance in ohms shall be at least equal to the resistance of the resistance of the resistor which would dissipate the same power as the LED module-controlgear combination when operating at its rated voltage and frequency. The controlgear impedance is measured with a signal voltage equal to 3,5% of the rated supply voltage of the controlgear. Between 250 Hz and 400 Hz, the impedance shall be at least equal to half the minimum value required from frequencies between 400 Hz to 2 000 Hz. (IEC 62384)

Operational tests for abnormal conditions

The controlgear shall not be damaged under operational test for abnormal conditions such as no LED module(s) inserted, reduced LED module resistance and short-circuit (if short-circuit proof type). After test simulating these conditions and after restoration of a possible protecting device, the controlgear shall function normally. (IEC 62384)

Endurance

To proof its endurance a controlgear must be subjected to a temperature cycling shock test and supply voltage switching test. At the end of these test the controlgear shall operate an appropriate LED module or LED modules correctly for 15 min. Temperature

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cycling shock test is made up of five cycles, in which the non-energised controlgear is stored firstly at -10C (or lower value, if marked) for 1 h and then the controlgear is moved into a cabinet having a temperature of rated maximum operating temperature of the case of a controlgear (tc) and stored for 1 h. Supply voltage switching test consists of 200 cycles with no load and 800 cycles with maximum load conditions of switching controlgear on and off for 30 s. After these tests the controlgear shall then be operated with appropriate LED modules at rated supply voltage and at the ambient temperature, which produces tc, until a test period of 200 h has passed. At the end of this period, and after cooling down to room temperature, the controlgear shall operate appropriate LED modules correctly for 15 min. (IEC 62384)

Product life and failure rate

It is recommended in IEC 62384 that manufacturer would provide in a product catalogue the maximum surface temperature (tl) that allows a life of 50 000 h to be achieved and the failure rate at the maximum temperature (tl).

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Conclusions

Lighting solutions utilising LEDs are increasing with wide leaps. In the future, a major part of light produced is most likely from them. LEDs certainly have features, such as great potential to very good energy efficiency and colour mixing capabilities that are seen very positive. Presently, however, the lack of standardisation and common criteria to meaningfully compare different products are seen as one important disadvantage of projecting with LEDs.

General safety requirements for luminaires have been available already for years and, of course, also LED luminaires must meet those requirements. At the moment, there are no performance requirements for luminaires but for LED luminaires the standardisation is in progress. The performance requirements are really needed for luminaries, since presently it is hard to meaningfully compare different LED luminaries based on information presented by manufacturers in their catalogues. Also controlgear for LED modules must meet the general and particular requirements for safety. For controlgear there are already performance requirements standardised on international level. They form a guideline to manufacturers in presenting necessary information on their products. Despite there is international performance standard for controlgear, only few controlgear manufacturers publish information about product life and failure rate. Since users do not have long-term experience on using LED controlgear, it is natural that users are cautious to invest in large-scale to LED lighting systems.

As further technological development continues and the efficiency, light output, reliability of LED lighting solutions improve and costs are getting more competitive against conventional solutions, the utilisation of LED luminaires would be possible in large-scale installations in general lighting.

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