oSIST prEN IEC 61820-3-4:2022

Electrical installations for lighting and beaconing of aerodromes - Safety secondary circuits in series circuits - General safety requirements

Elektrische Anlagen für Beleuchtung und Befeuerung von Flugplätzen – Sicherheitssekundärkreise in Serienschaltung – Allgemeine Sicherheitsanforderungen

Installations électriques pour l'éclairage et le balisage des aérodromes - Circuits secondaires de sécurité dans des circuits série - Exigences générales de sécurité

Električne inštalacije za razsvetljavo in radijske javljalnike na letališčih - Sekundarni varnostni tokokrogi v seriji vezij - Splošne varnostne zahteve

General Information

• Status: Not Published
• Public Enquiry End Date: 31-Oct-2022
• ICS: 29.140.50 - Lighting installation systems
• ICS: 49.100 - Ground service and maintenance equipment
• ICS: 93.120 - Construction of airports
• Technical Committee: I09 - Imaginarni 09
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 25-Aug-2022
• Due Date: 12-Jan-2023
• Completion Date: 10-Nov-2022
• Ref Project: prEN IEC 61820-3-4:2022 - Electrical installations for lighting and beaconing of aerodromes - Safety secondary circuits in series circuits - General safety requirements

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN IEC 61820-3-4:2022
01-oktober-2022
Električne inštalacije za razsvetljavo in radijske javljalnike na letališčih -
Sekundarni varnostni tokokrogi v seriji vezij - Splošne varnostne zahteve

Electrical installations for lighting and beaconing of aerodromes - Safety secondary

circuits in series circuits - General safety requirements

Installations électriques pour l'éclairage et le balisage des aérodromes - Circuits

secondaires de sécurité dans des circuits série - Exigences générales de sécurité

Ta slovenski standard je istoveten z: prEN IEC 61820-3-4:2022
ICS:
29.140.50 Instalacijski sistemi za Lighting installation systems
razsvetljavo
49.100 Oprema za servis in Ground service and
vzdrževanje na tleh maintenance equipment
93.120 Gradnja letališč Construction of airports
oSIST prEN IEC 61820-3-4:2022 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN IEC 61820-3-4:2022
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oSIST prEN IEC 61820-3-4:2022
97/238/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 61820-3-4 ED1
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2022-08-19 2022-11-11
SUPERSEDES DOCUMENTS:
97/233/CD, 97/236/CC
IEC TC 97 : ELECTRICAL INSTALLATIONS FOR LIGHTING AND BEACONING OF AERODROMES
SECRETARIAT: SECRETARY:
Spain Mrs Carmen Martín Marino
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:
SC 34A,SC 34D
Other TC/SCs are requested to indicate their interest, if
any, in this CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY

SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING

Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft
for Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.

This document is still under study and subject to change. It should not be used for reference purposes.

Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of

which they are aware and to provide supporting documentation.
TITLE:

Electrical installations for lighting and beaconing of aerodromes - Safety secondary circuits in

series circuits - General safety requirements
PROPOSED STABILITY DATE: 2027
NOTE FROM TC/SC OFFICERS:

Copyright © 2022 International Electrotechnical Commission, IEC. All rights reserved. It is permitted to

download this electronic file, to make a copy and to print out the content for the sole purpose of preparing National

Committee positions. You may not copy or "mirror" the file or printed version of the document, or any part of it, for

any other purpose without permission in writing from IEC.
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1 CONTENTS

2 CONTENTS ......................................................................................................................................... 1

3 INTERNATIONAL ELECTROTECHNICAL COMMISSION ................................................................. 3

4 FOREWORD ........................................................................................................................................ 3

5 INTRODUCTION .................................................................................................................................. 5

6 1 Scope ................................................................................................................................... 6

7 2 Normative references .......................................................................................................... 6

8 3 Terms and definitions .......................................................................................................... 7

9 4 Requirements for the SELV/PELV supply ......................................................................... 10

10 4.1 General .............................................................................................................................. 10

11 4.2 SELV/PELV-safety demarcation line in an AGL series circuit ........................................... 11

12 4.3 Environmental conditions .................................................................................................. 12

13 4.4 Degree of protection provided by enclosures .................................................................... 12

14 4.6 Marking .............................................................................................................................. 12

15 4.7 Protection against electric shock ....................................................................................... 13

16 4.8 Interfaces ........................................................................................................................... 16

17 5 Useful methodic for a SELV/PELV series circuit configuration ......................................... 16

18 5.1 Method: systemic approach ............................................................................................... 16

19 5.2 Method: extended systemic approach (with limiter) .......................................................... 17

20 5.3 Verification of the chosen method ..................................................................................... 17

21 6 Testing ............................................................................................................................... 17

22 6.1 System design test ............................................................................................................ 17

23 6.2 Production Routine tests ................................................................................................... 20

24 6.3 Field test ............................................................................................................................ 21

25 Annex A (informative) System design selection .......................................................................... 23

26 Annex B (informative) Marking and hazard risk information ........................................................ 24

27 B1 Examples for marking ........................................................................................................ 24

28 B2 Hazard risk information ...................................................................................................... 27

29 B3 Measurement information .................................................................................................. 27

30 Annex C (informative) ........................................................................................................................ 30

31 C1 Determination of the peak voltage for SELV/PELV applications .............................................. 30

32 Bibliography ..................................................................................................................................... 39

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39 INTERNATIONAL ELECTROTECHNICAL COMMISSION
40 ____________
42 ELECTRICAL INSTALLATIONS FOR
43 LIGHTING AND BEACONING OF AERODROMES –
44 SAFETY SECONDARY CIRCUITS IN SERIES CIRCUITS –
47 GENERAL SAFETY REQUIREMENTS
49 FOREWORD

50 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national

51 electrotechnical committees (IEC National Committees). The object of IEC is to promote international co-operation on all

52 questions concerning standardization in the electrical and electronic fields. To this end and in addition to other activities, IEC

53 publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specifications (PAS) and

54 Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is entrusted to technical committees, any IEC

55 National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental

56 and nongovernmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with

57 the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between

58 the two organizations.

59 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international consensus

60 of opinion on the relevant subjects since each technical committee has representation from all interested IEC National

61 Committees.

62 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in

63 that sense. While all reasonable efforts are made to ensure that the technical content of IEC Publications is accurate, IEC

64 cannot be held responsible for the way in which they are used or for any misinterpretation by any end user.

65 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently to

66 the maximum extent possible in their national and regional publications. Any divergence between any IEC Publication and

67 the corresponding national or regional publication shall be clearly indicated in the latter.

68 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity assessment

69 services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any services carried out by

70 independent certification bodies.

71 6) All users should ensure that they have the latest edition of this publication.

72 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and members of its

73 technical committees and IEC National Committees for any personal injury, property damage or other damage of any nature

74 whatsoever, whether direct or indirect, or for costs (including legal fees) and expenses arising out of the publication, use of,

75 or reliance upon, this IEC Publication or any other IEC Publications.

76 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable

77 for the correct application of this publication.

78 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights.

79 IEC shall not be held responsible for identifying any or all such patent rights.

80 International Standard IEC 61820-3-4 has been prepared by IEC technical committee 97: Electrical

81 installations for lighting and beaconing of aerodromes.
82 The text of this standard is based on the following documents:
FDIS Report on voting
97/XXX/FDIS 97/XXX/RVD

84 Full information on the voting for the approval of this standard can be found in the report on voting

85 indicated in the above table.

86 This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

87 The committee has decided that the contents of this publication will remain unchanged until the

88 stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to the

89 specific publication. At this date, the publication will be
90 • reconfirmed,
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91 • withdrawn,
92 • replaced by a revised edition, or
93 • amended.

95 IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates that it

96 contains colours which are considered to be useful for the correct understanding of its

97 contents. Users should therefore print this document using a colour printer.
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99 INTRODUCTION

100 With a few exceptions, aeronautical ground lighting is designed for series circuit technology operating

101 with a constant current and a maximum input voltage of 5 000 V AC rms, including tolerances. The

102 input voltage to the series circuit is constantly adjusted by the constant current regulator to maintain

103 the series circuit current irrespective of the variations in the load. The properties and characteristics of

104 the constant current regulators are provided in IEC 61822. Due to the structure of the series circuit,

105 i.e., a series connection of all loads, the usual protective devices for personnel protection of an IT, TT

106 or TN network cannot be applied.

107 Aeronautical ground lighting is defined as any light provided as an aid to air navigation and as such is

108 subject to specific requirements with respect to its resilience, availability, and serviceability levels.

109 Therefore, insulation faults in the series circuit are often tolerated, and do not lead to the automatic

110 disconnection of the electrical supply to the series circuit.

111 In view of the above IEC 61821 states that no work of any kind is normally permitted on live series

112 circuits without first conducting a suitable and sufficient Risk Assessment and using appropriate

113 protective equipment according to IEC 61821.

114 The electrical characteristics of the constant current series circuits are often confused with those of IT,

115 TT or TN networks, i.e., constant input voltage, equipment connected in parallel, and a load-

116 dependent current. In practice, it is not always easy to assign rated voltages correctly to individual

117 components of the series circuit or to determine possible touch voltages. In a constant current series

118 circuit, the rated voltage of the equipment in the series circuit and the maximum touch voltage

119 frequently exceed the normal mains input voltage.

120 In a series circuit installation, the series circuit input voltage is divided in proportion to the internal

121 resistances of the various loads. The rated voltage, i.e., the voltage between the input lines of the

122 equipment, is defined by the series circuit current that flows through the equipment and its input

123 impedance. Since input impedance depends on the equipment design and the series circuit current is

124 constant, the input voltage remains the same for each item of equipment. As a result of the provision

125 of current control in the series circuit the series circuit input voltage is load-dependent and

126 corresponds to the sum of all partial voltages in the series circuit.

127 This is different to determining the maximum possible touch voltage to earth in a series circuit. Since

128 one or more earth faults of varying resistance to earth maybe present, the touch voltage to earth may

129 assume any value up to the maximum series circuit input voltage depending on the location of the

130 earth fault and the equipment installed in the series circuit. Therefore, when determining the dielectric

131 strength against earth potential it is usual to take the maximum series circuit input voltage. Such

132 peculiarities of the series circuit have been considered in the requirements for lamp systems in this

133 standard.

134 Since there are only a few effective safety features available for personnel protection in series circuit

135 technology the protective measure “Safety extra low voltage (SELV)” and “Protective extra low voltage

136 (PELV)” is applied in this standard for the supply of lamp systems. This measure is common practice

137 and can resort to the application of well-known and accepted methodology. The introduction of

138 SELV/PELV in this type of application has been made possible by the introduction of new illuminant

139 technology that has lower power requirements and hence requires a lower voltage supply.

140 NOTE This standard is based on SELV specification according to IEC 60364-4-41 and IEC 61558-1.

141
142
143
144
145
146
147
148
149
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150 ELECTRICAL INSTALLATIONS FOR
151 LIGHTING AND BEACONING OF AERODROMES –
152 ELV SAFETY SECONDARY CIRCUITS IN SERIES CIRCUITS –
153 GENERAL SAFETY REQUIREMENTS
154
155
156
157 1 Scope

158 This International Standard specifies protective provisions for the operation of lamp systems powered

159 by series circuits in aeronautical ground lighting.

160 The protective provisions described here refer only to secondary supply systems for loads that are

161 electrically separated from the series circuit.

162 This standard specifies the level of SELV, and alternatively PELV, under consideration of additional

163 personnel protection during work on live secondary circuits by electrically skilled persons. This

164 standard also covers the special operational features of aeronautical ground lighting and addresses

165 the level of training and the requirements for maintenance procedures detailed in IEC 61821 and other

166 national or regional regulation.

167 The requirements and tests are intended to set a specification framework for system designers,

168 system installers, users, and maintenance personnel to ensure a safe and economic use of electrical

169 systems in installations for the beaconing of aerodromes.

170 This standard complements existing IEC Aeronautical-Ground- Lighting (AGL) standards and can be

171 used as a design specification.
172 2 Normative references

173 The following documents, in whole or in part, are normatively referenced in this document and are

174 indispensable for its application. For dated references, only the edition cited applies. For undated

175 references, the latest edition of the referenced document (including any amendments) applies.

176 IEC 60364-4-41 (2005-12), Low-voltage electrical installations – Part 4-41: Protection for safety –

177 Protection against electric shock
178 IEC 60417 (2002-10), Graphical symbols for use on equipment (available from:
179 http://www.graphicalsymbols.info/equipment)
180 IEC 60529 (2013-08), Degrees of protection provided by enclosures (IP Code)

181 IEC 61000-6-2 (2016-08), Electromagnetic compatibility (EMC) – Part 6-2: Generic standards –

182 Immunity for industrial environments

183 IEC 61000-6-4 (2018-02), Electromagnetic compatibility (EMC) – Part 6-4: Generic standards –

184 Emission standard for industrial environments

185 IEC 61140 (2016-01), Protection against electric shock – Common aspects for installation and

186 equipment

187 IEC 61821 (2011-09), Electrical installations for lighting and beaconing of aerodromes - Maintenance

188 of aeronautical ground lighting constant current series circuits

189 IEC 61558-2-4 (2009-02), Safety of transformers, reactors, power supply units and similar products for

190 supply voltages up to 1 100 V – Part 2-4: Particular requirements and tests for isolating transformers

191 and power supply units incorporating isolating transformers
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192 IEC 61558-2-6 (2009-02), Safety of transformers, reactors, power supply units and similar products for

193 supply voltages up to 1 100 V – Part 2-6: Particular requirements and tests for safety isolating

194 transformers and power supply units incorporating safety isolating transformers

195 IEC 61820-1-1 (2019-05) Electrical installations for aeronautical ground lighting at aerodromes –Part

196 1: Fundamental principles

197 IEC 61820-1-2 (2019-05) Electrical installations for aeronautical ground lighting at aerodromes –Part

198 2: Requirements for series circuits

199 IEC 61820-3-2 (2020-07) (61822 old version), Electrical installations for lighting and beaconing of

200 aerodromes – Constant current regulators

201 IEC 61820-4-2 (2002-12) (61823 old version), Electrical installations for lighting and beaconing of

202 aerodromes – AGL series transformers

203 IEC 61820-3-2 (2020-07) (61821 old version), Electrical installations for lighting and beaconing of

204 aerodromes – Maintenance of aeronautical ground lighting constant current series circuits

205 IEC 60479-1 (2018-12) Effects Of Current On Human Beings And Livestock - Part 1: General Aspects

206 IEC 60479-2 (Ed. 1.0, 2019-05) Effects of current on human beings and livestock – Part 2: Special

207 aspects

208 IEC 63067 (2020-06) Electrical installations for lighting and beaconing of aerodromes - Connecting

209 devices – General requirements and tests

210 CISPR 11 (2015-06), Industrial, scientific, and medical equipment – Radio-frequency disturbance

211 characteristics – Limits and methods of measurement

212 CISPR 22 (2008-09), Information technology equipment – Radio disturbance characteristics – Limits

213 and methods of measurement
214 3 Terms and definitions

215 For the purposes of this document, the following terms and definitions apply.

216 3.1
217 assembly

218 self-contained, closed functional unit forming a light system together with other assemblies

219 3.2
220 basic insulation
221 insulation of hazardous live parts providing basic protection
222 [SOURCE: IEC 60050-581:2008, 581-21-24]

223 Note 1 to entry: This concept does not apply insulation used exclusively for functional purposes.

224 3.3
225 electrically skilled person

226 person with relevant education and experience to enable that person to perceive risks and to avoid

227 hazards which electricity can create
228 [SOURCE: IEC 60050-195:1998,195-04-01]
229 3.4
230 extra-low voltage
231 ELV
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232 voltage not exceeding the relevant voltage limit specified in 4.7.3
233 3.5
234 safety extra-low voltage
235 SELV

236 voltage values of which does not exceed values in 4.7.3, between conductors, or between any

237 conductor and reference earth, in an electric circuit which has galvanic separation from the supplying

238 electric power system by such means as a separate-winding transformer
239 3.6
240 SELV system

241 electrical system in which the voltage cannot exceed the value of extra-low voltage:

242 – under normal conditions, and

243 – under single-fault conditions, including earth faults in other electric circuits

244 Note 1 to entry: SELV is the abbreviation for safety extra low voltage.
245 [SOURCE: IEC 60050-826:2004, 826-12-31]
246 3.7
247 PELV system

248 Electric system in which the voltage cannot exceed the value of extra low voltage

249 - under normal conditions and

250 - under single fault conditions, including earth faults in other electric cricuits

251
252 Note 1 to entry: PELV is the abbreviation for protective extra low voltage
253
254 3.8
255 SELV/PELV power supply

256 single physical unit or an assembly of physical units performing as the power supply according to

257 SELV/PELV definitions
258 3.9
259 protective separation
260 separation of one electric circuit from another by means of:
261 – double insulation or
262 – basic insulation and electrically protective screening or
263 – reinforced insulation
264 3.10
265 power supply unit

266 all components for the supply and transfer of energy used to operate a lighting unit in a series circuit

267 3.11
268 electric shock

269 physiological effect resulting from an electric current passing through a human or animal body

270 [SOURCE: IEC 60050-195:1998, 195-01-04]
271 3.12
272 hazardous live part
273 live part which, under certain conditions, can give a harmful electric shock
274 [SOURCE: IEC 60050-195:1998, 195-06-05]
275 3.13
276 touch voltage

277 voltage between conductive parts when touched simultaneously by a person or an animal

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278 Note 1 to entry: The value of the effective touch voltage may be appreciably influenced by the impedance of the person or the

279 animal in electric contact with these conductive parts.

280 [SOURCE: IEC 60050-195:1998, 195-05-11, modified by suppression of “effective touch voltage”]

281 3.14
282 single fault condition

283 condition in which there is a fault of a single protection (but not a reinforced protection) or of a single

284 component or a device
285 [SOURCE: IEC 60050-903:2013, 903-01-15]
286 3.15
287 light fixture (US)
288 light fitting (UK)
289 luminaire

290 electrical device used to create artificial light by use of an electric lamp/LED/light source above ground

291 or within the pavement

292 Note 1 to entry: The luminaire is an apparatus which distributes, filters or transforms the light transmitted from one or more

293 lamps and which includes all the parts necessary for supporting, aiming, fixing and protecting the lamps, but not the lamps

294 themselves and, where necessary, circuit auxiliaries together with the means for connecting them to supply.

295 3.16
296 limiter

297 device which limits the safety transformer output voltage to a defined maximum value

298 Note 1 to entry: The probability of electric shock increases with voltage level, surface area of the accessible conductive part or

299 circuit in contact with the skin and the humidity condition of skin.
300 3.17
301 Safety transformer

302 Isolating transformer with protective separation between the input winding(s) and output winding(s)

303 [SOURCE: IEC 61558-1]
304
305 3.18
306 dry condition

307 skin condition of a surface area of contact with regards to humidity of a living person being at rest

308 under normal indoor condition
309 3.19 – Abbreviations
310 AGL = Aeronautical Ground Lighting
311 IP = code to define the degree of protection of an enclosure
312 ELV = Extra Low Voltage
313 EMC = Electromagnetic Compatibility
314 CISPR = International Special Committee on Radio Interference
315 AC = Alternating Curent
316 DC = Direct Curent
317 CCR = Constant Current Regulator
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318 DUT = Device Under Test
319 ISO = International Standard Organization
320 IEC = International Electrotechnical Commission
321 ILCMS = Integrated Lamp Control and Monitoring System
322 4 Requirements for the SELV/PELV supply
323 4.1 General

324 Light fittings/light fixtures/luminaires for use in aeronautical ground lighting shall be designed for use in

325 a series circuit. The maximum power ratings of the series circuit supply are given by the constant

326 current regulators according to IEC 61822. If the light systems are designed for other current ranges,

327 such information shall be provided by the manufacturer.
328 The series circuit shall be designed for a nominal system voltage of:

329 Class V2: nominal system voltage up to and including 1000 V AC according to IEC 61820-1-1;

330 subclause 6.3 and IEC61820-1-2; subclause 6.3.2

331 The design of the safety secondary circuit shall support safe working conditions for electrically skilled

332 persons.

333 The maintenance practices shall follow IEC 61821 and applicable national or regional regulations.

334 When considering live work on the secondary circuit the risk assessment should consider the nature of

335 the work (fault finding, testing, and repair), the nature of the hazards present, and the provision of

336 SELV/PELV designs.

337 The recommendation is to implement a PELV design because it is considered the more practical

338 solution over complete lifetime of the installation but with the same safety level as a SELV design. If

339 this requirement cannot be fulfilled, then it shall be considered that you need to enforce maintenance

340 effort to achieve a suitable insulation level to implement the SELV design.

341 NOTE 1: The present standard does not consider any specific requirements regarding to the lightning over voltages. The

342 SELV/PELV voltage is no more guaranteed in case of lightning that can happen on or at proximity of any of the component of

343 the system.
344
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345 4.2 SELV/PELV-safety demarcation line in an AGL series circuit

346 Figure 1 and Figure 2 below show the extent of the safety secondary system. The safety secondary

347 system (limit defined in 4.7.3) is all circuitry below the dashed red safety demarcation line.

348

349 Figure 1 – Safety demarcation line in a safety extra low voltage system (SELV system)

350 Uinput shall not exceed 1kV AC rms
351

352 Figure 2 – Safety demarcation line in a protective extra low voltage system (PELV system)

353 U shall not exceed 1kV AC rms
input

354 NOTE 1 The given earthing in this figure is an example. The earthing connection can be performed anywhere in the secondary

355 circuit.
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