Insulation coordination for equipment within low-voltage supply systems - Part 1: Principles, requirements and tests (IEC 60664-1:2020)

This part of IEC 60664 deals with insulation coordination for equipment having a
rated voltage up to AC 1 000 V or DC 1 500 V connected to low-voltage supply systems.
This document applies to frequencies up to 30 kHz.
NOTE 1 Requirements for insulation coordination for equipment within low-voltage supply systems with rated
frequencies above 30 kHz are given in IEC 60664-4.
NOTE 2 Higher voltages can exist in internal circuits of the equipment.
It applies to equipment for use up to 2 000 m above sea level and provides guidance for use
at higher altitudes (See 5.2.3.4).
It provides requirements for technical committees to determine clearances, creepage
distances and criteria for solid insulation. It includes methods of electrical testing with
respect to insulation coordination.
The minimum clearances specified in this document do not apply where ionized gases are
present. Special requirements for such situations can be specified at the discretion of the
relevant technical committee.
This document does not deal with distances:
– through liquid insulation;
– through gases other than air;
– through compressed air.
This basic safety publication focusing on safety essential requirements is primarily intended
for use by technical committees in the preparation of standards in accordance with the
principles laid down in IEC Guide 104 and ISO/IEC Guide 51.
One of the responsibilities of a technical committee is, wherever applicable, to make use of
basic safety publications in the preparation of its publications.
However, in case of missing specified values for clearances, creepage distances and
requirements for solid insulation in the relevant product standards, or even missing
standards, this document applies.

Isolationskoordination für elektrische Betriebsmittel in Niederspannungsanlagen - Teil 1: Grundsätze, Anforderungen und Prüfungen (IEC 60664-1:2020)

Coordination de l'isolement des matériels dans les réseaux d'énergie électrique à basse tension - Partie 1: Principes, exigences et essais (IEC 60664-1:2020)

L’IEC 60664-1:2020 traite de la coordination de l'isolement des matériels ayant une tension assignée allant jusqu’à 1 000 V en courant alternatif ou jusqu’à 1 500 V en courant continu connectés aux réseaux d’énergie électrique à basse tension. Le présent document s’applique aux fréquences jusqu’à 30 kHz inclus. NOTE 1 Les exigences de coordination de l’isolement des matériels dans les réseaux d’énergie électrique à basse tension dont les fréquences assignées sont supérieures à 30 kHz sont données dans l’IEC 60664-4. NOTE 2 Des tensions plus élevées peuvent exister dans les circuits internes des matériels. Il s'applique au matériel utilisé jusqu'à 2 000 m au-dessus du niveau de la mer, et fournit des recommandations pour l’utilisation à des altitudes plus élevées (Voir  REF _Ref452123764 \r \h \* MERGEFORMAT 5.2.3.4 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000E0000005F005200650066003400350032003100320033003700360034000000 ). Il définit les exigences permettant aux comités d’études de déterminer les distances d'isolement, les lignes de fuite et les critères pour l’isolation solide. Il comprend les méthodes d'essais diélectriques concernant la coordination de l'isolement. Les distances d'isolement minimales spécifiées dans le présent document ne s'appliquent pas en présence de gaz ionisés. Les exigences particulières dans de telles conditions peuvent être spécifiées, comme ils l'entendent, par les comités d'études compétents. Le présent document ne traite pas des distances: – à travers l'isolation liquide; – à travers les gaz autres que l'air; – à travers l'air comprimé. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:  mise à jour du Domaine d’application et des Articles 2 et 3, nouvelle structure pour les Articles 4 et 5, ajout de 1 500 V en courant continu dans les tableaux dans Annexe B et F, mise à jour de la correction de l’altitude des distances dans un nouveau Tableau F.10, ajout d’une Annexe G avec un organigramme relatif aux distances d’isolement, ajout d’une Annexe H avec un organigramme relatif aux lignes de fuite.  Elle a le statut d’une publication fondamentale de sécurité conformément au Guide 104 de l’IEC.

Koordinacija izolacije za opremo v okviru nizkonapetostnih sistemov - 1. del: Načela, zahteve in preskusi (IEC 60664-1:2020)

General Information

Status
Published
Publication Date
01-Sep-2020
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
12-Aug-2020
Due Date
17-Oct-2020
Completion Date
02-Sep-2020

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SLOVENSKI STANDARD
SIST EN IEC 60664-1:2020
01-oktober-2020
Nadomešča:
SIST EN 60664-1:2007
Koordinacija izolacije za opremo v okviru nizkonapetostnih sistemov - 1. del:
Načela, zahteve in preskusi (IEC 60664-1:2020)

Insulation coordination for equipment within low-voltage supply systems - Part 1:

Principles, requirements and tests (IEC 60664-1:2020)

Isolationskoordination für elektrische Betriebsmittel in Niederspannungsanlagen - Teil 1:

Grundsätze, Anforderungen und Prüfungen (IEC 60664-1:2020)

Coordination de l'isolement des matériels dans les réseaux d'énergie électrique à basse

tension - Partie 1: Principes, exigences et essais (IEC 60664-1:2020)
Ta slovenski standard je istoveten z: EN IEC 60664-1:2020
ICS:
29.080.30 Izolacijski sistemi Insulation systems
SIST EN IEC 60664-1:2020 en

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

---------------------- Page: 1 ----------------------
SIST EN IEC 60664-1:2020
---------------------- Page: 2 ----------------------
SIST EN IEC 60664-1:2020
EUROPEAN STANDARD EN IEC 60664-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2020
ICS 29.080.30 Supersedes EN 60664-1:2007 and all of its amendments
and corrigenda (if any)
English Version
Insulation coordination for equipment within low-voltage supply
systems - Part 1: Principles, requirements and tests
(IEC 60664-1:2020)

Coordination de l'isolement des matériels dans les réseaux Isolationskoordination für elektrische Betriebsmittel in

d'énergie électrique à basse tension - Partie 1: Principes, Niederspannungsanlagen - Teil 1: Grundsätze,

exigences et essais Anforderungen und Prüfungen
(IEC 60664-1:2020) (IEC 60664-1:2020)

This European Standard was approved by CENELEC on 2020-06-30. CENELEC members are bound to comply with the CEN/CENELEC

Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC

Management Centre or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the

same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,

Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the

Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2020 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Ref. No. EN IEC 60664-1:2020 E
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SIST EN IEC 60664-1:2020
EN IEC 60664-1:2020 (E)
European foreword

The text of document 109/183/FDIS, future edition 3 of IEC 60664-1, prepared by IEC/TC 109

"Insulation co-ordination for low-voltage equipment" was submitted to the IEC-CENELEC parallel vote

and approved by CENELEC as EN IEC 60664-1:2020.
The following dates are fixed:

• latest date by which the document has to be implemented at national (dop) 2021-03-30

level by publication of an identical national standard or by endorsement

• latest date by which the national standards conflicting with the (dow) 2023-06-30

document have to be withdrawn

This document supersedes EN 60664-1:2007 and all of its amendments and corrigenda (if any).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

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

Endorsement notice

The text of the International Standard IEC 60664-1:2020 was approved by CENELEC as a European

Standard without any modification.

In the official version, for Bibliography, the following notes have to be added for the standards

indicated:
IEC 60038:2009 NOTE Harmonized as EN 60038:2011 (modified)
IEC 60216 (series) NOTE Harmonized as EN 60216 (series)
IEC 60068 (series) NOTE Harmonized as EN 60068 (series)
IEC 60068-1:2013 NOTE Harmonized as EN 60068-1:2014 (not modified)
IEC 60085:2007 NOTE Harmonized as EN 60085:2008 (not modified)
IEC 60112:2003 NOTE Harmonized as EN 60112:2003 (not modified)
IEC 60364-4-44:2007 NOTE Harmonized as HD 60364-4-442:2012 (modified)
IEC 60529 NOTE Harmonized as EN 60529
IEC 60664-3:2016 NOTE Harmonized as EN 60664-3:2017 (not modified)
IEC 60664-4:2005 NOTE Harmonized as EN 60664-4:2006 (not modified)
IEC 61000-4-5:2014 NOTE Harmonized as EN 61000-4-5:2014 (not modified)
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SIST EN IEC 60664-1:2020
EN IEC 60664-1:2020 (E)
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments)

applies.

NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod), the relevant

EN/HD applies.

NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available here:

www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60068-2-2 - Environmental testing - Part 2-2: Tests - EN 60068-2-2 -
Test B: Dry heat

IEC 60068-2-14 2009 Environmental testing - Part 2-14: Tests - EN 60068-2-14 2009

Test N: Change of temperature
IEC 60068-2-78 - Environmental testing - Part 2-78: Tests - EN 60068-2-78 -
Test Cab: Damp heat, steady state
IEC 60270 - High-voltage test techniques - Partial EN 60270 -
discharge measurements
IEC 61140 2016 Protection against electric shock - EN 61140 2016
Common aspects for installation and
equipment
IEC 61180 2016 High-voltage test techniques for low- EN 61180 2016
voltage equipment - Definitions, test and
procedure requirements, test equipment
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SIST EN IEC 60664-1:2020
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SIST EN IEC 60664-1:2020
IEC 60664-1
Edition 3.0 2020-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
BASIC SAFETY PUBLICATION
PUBLICATION FONDAMENTALE DE SÉCURITÉ
Insulation coordination for equipment within low-voltage supply systems –
Part 1: Principles, requirements and tests
Coordination de l’isolement des matériels dans les réseaux d’énergie électrique
à basse tension –
Partie 1: Principes, exigences et essais
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.080.30 ISBN 978-2-8322-8287-8

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 7 ----------------------
SIST EN IEC 60664-1:2020
– 2 – IEC 60664-1:2020 © IEC 2020
CONTENTS

FOREWORD ........................................................................................................................... 6

1 Scope .............................................................................................................................. 8

2 Normative references ...................................................................................................... 8

3 Terms, definitions and abbreviated terms ........................................................................ 9

3.1 Terms and definitions .............................................................................................. 9

3.2 Abbreviated terms ................................................................................................. 15

4 Basic technical characteristics for insulation coordination .............................................. 15

4.1 General ................................................................................................................. 15

4.2 Voltages ............................................................................................................... 16

4.2.1 General aspects ............................................................................................ 16

4.2.2 Transient overvoltages .................................................................................. 17

4.2.3 Temporary overvoltages ................................................................................ 18

4.2.4 Recurring peak voltage .................................................................................. 18

4.2.5 Steady-state working voltage ......................................................................... 19

4.2.6 Steady-state peak voltage ............................................................................. 19

4.3 Overvoltage categories ......................................................................................... 19

4.3.1 General ......................................................................................................... 19

4.3.2 Equipment energized directly from the mains supply ...................................... 19

4.3.3 Systems and equipment not energized directly from the mains supply ........... 20

4.4 Frequency ............................................................................................................. 20

4.4.1 General ......................................................................................................... 20

4.4.2 Solid insulation .............................................................................................. 20

4.5 Pollution ............................................................................................................... 20

4.5.1 General ......................................................................................................... 20

4.5.2 Degrees of pollution in the micro-environment ............................................... 21

4.5.3 Conditions of conductive pollution.................................................................. 21

4.6 Insulating material ................................................................................................ 21

4.6.1 Solid insulation .............................................................................................. 21

4.6.2 Stresses ........................................................................................................ 22

4.6.3 Comparative tracking index (CTI) .................................................................. 23

4.7 Environmental aspects .......................................................................................... 24

4.7.1 General ......................................................................................................... 24

4.7.2 Altitude .......................................................................................................... 24

4.7.3 Temperature .................................................................................................. 24

4.7.4 Vibrations ...................................................................................................... 24

4.7.5 Humidity ........................................................................................................ 24

4.8 Duration of voltage stress ..................................................................................... 24

4.9 Electrical field distribution ..................................................................................... 25

5 Design for insulation coordination .................................................................................. 25

5.1 General ................................................................................................................. 25

5.1.1 Means of insulation coordination .................................................................... 25

5.1.2 Frequency above 30 kHz ............................................................................... 25

5.1.3 Reduced distances due to coating or potting .................................................. 25

5.1.4 Equipment which are not connected to public low-voltage systems. ............... 25

5.2 Dimensioning of clearances .................................................................................. 25

5.2.1 General ......................................................................................................... 25

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SIST EN IEC 60664-1:2020
IEC 60664-1:2020 © IEC 2020 – 3 –

5.2.2 Dimensioning criteria for clearances .............................................................. 26

5.2.3 Other factors involving clearances ................................................................. 26

5.2.4 Dimensioning of clearances of functional insulation ....................................... 27

5.2.5 Dimensioning of clearances of basic insulation, supplementary

insulation and reinforced insulation ................................................................ 27

5.3 Dimensioning of creepage distances ..................................................................... 28

5.3.1 General ......................................................................................................... 28

5.3.2 Dimensioning criteria of creepage distances .................................................. 29

5.3.3 Other factors involving creepage distances .................................................... 30

5.3.4 Dimensioning of creepage distances of functional insulation .......................... 31

5.3.5 Dimensioning of creepage distances of basic insulation, supplementary

insulation and reinforced insulation ................................................................ 31

5.4 Requirements for design of solid insulation ........................................................... 32

5.4.1 General ......................................................................................................... 32

5.4.2 Voltage stress................................................................................................ 32

5.4.3 Withstand of voltage stresses ........................................................................ 32

5.4.4 Withstand on environmental stresses ............................................................. 34

6 Tests and measurements ............................................................................................... 34

6.1 General ................................................................................................................. 34

6.2 Verification of clearances ...................................................................................... 35

6.2.1 General ......................................................................................................... 35

6.2.2 Test voltages ................................................................................................. 35

6.3 Verification of creepage distances ........................................................................ 37

6.4 Verification of solid insulation ............................................................................... 37

6.4.1 General ......................................................................................................... 37

6.4.2 Selection of tests ........................................................................................... 38

6.4.3 Conditioning .................................................................................................. 39

6.4.4 Impulse voltage test ....................................................................................... 39

6.4.5 AC power frequency voltage test ................................................................... 40

6.4.6 Partial discharge test ..................................................................................... 40

6.4.7 DC voltage test .............................................................................................. 42

6.4.8 High-frequency voltage test ........................................................................... 43

6.5 Performing dielectric tests on complete equipment................................................ 43

6.5.1 General ......................................................................................................... 43

6.5.2 Parts to be tested .......................................................................................... 43

6.5.3 Preparation of equipment circuits ................................................................... 44

6.5.4 Test voltage values ........................................................................................ 44

6.5.5 Test criteria ................................................................................................... 44

6.6 Other tests ............................................................................................................ 44

6.6.1 Test for purposes other than insulation coordination ...................................... 44

6.6.2 Sampling and routine tests ............................................................................ 44

6.6.3 Measurement accuracy of test parameters ..................................................... 44

6.7 Measurement of the attenuation of the transient overvoltages ............................... 45

6.8 Measurement of clearances and creepage distances ............................................ 45

Annex A (informative) Basic data on withstand characteristics of clearances ....................... 51

Annex B (informative) Nominal voltages of mains supply for different modes of

overvoltage control ............................................................................................................... 56

Annex C (normative) Partial discharge test methods ............................................................ 58

C.1 Test circuits .......................................................................................................... 58

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SIST EN IEC 60664-1:2020
– 4 – IEC 60664-1:2020 © IEC 2020

C.1.1 General ......................................................................................................... 58

C.1.2 Test circuit for earthed test specimen (Figure C.1) ......................................... 58

C.1.3 Test circuit for unearthed test specimen (Figure C.2) ..................................... 59

C.1.4 Selection criteria ............................................................................................ 59

C.1.5 Measuring impedance .................................................................................... 59

C.1.6 Coupling capacitor C .................................................................................... 59

C.1.7 Filter .............................................................................................................. 59

C.2 Test parameters .................................................................................................... 59

C.2.1 General ......................................................................................................... 59

C.2.2 Requirements for the test voltage .................................................................. 60

C.2.3 Climatic conditions ........................................................................................ 60

C.3 Requirements for measuring instruments .............................................................. 60

C.3.1 General ......................................................................................................... 60

C.3.2 Classification of PD meters ............................................................................ 60

C.3.3 Bandwidth of the test circuit ........................................................................... 61

C.4 Calibration ............................................................................................................ 61

C.4.1 Calibration of discharge magnitude before the noise level measurement ....... 61

C.4.2 Verification of the noise level ......................................................................... 62

C.4.3 Calibration for the PD test ............................................................................. 63

C.4.4 Calibration pulse generator ............................................................................ 63

Annex D (informative) Additional information on partial discharge test methods ................... 64

D.1 Measurement of partial discharge (PD), PD inception and extinction voltage......... 64

D.2 Description of PD test circuits (Figure D.1) ........................................................... 64

D.3 Precautions for reduction of noise ......................................................................... 65

D.3.1 General ......................................................................................................... 65

D.3.2 Sources in the non-energized test circuit ....................................................... 65

D.3.3 Sources in the energized test circuit .............................................................. 65

D.3.4 Measures for reduction of noise ..................................................................... 65

D.4 Application of multiplying factors for test voltages ................................................. 65

D.4.1 General ......................................................................................................... 65

D.4.2 Example 1 (circuit connected to mains supply)............................................... 66

D.4.3 Example 2 (internal circuit with maximum recurring peak voltage U ) ........... 66

Annex E (informative) Comparison of creepage distances specified in Table F.5 and

clearances in Table A.1 ........................................................................................................ 67

Annex F (normative) Tables ................................................................................................. 68

Annex G (informative) Determination of clearance distances according to 5.2 ...................... 77

Annex H (informative) Determination of creepage distances according to 5.3 ....................... 79

Bibliography .......................................................................................................................... 81

Figure 1 – Recurring peak voltage ........................................................................................ 19

Figure 2 – Determination of the width (W) and height (H) of a rib .......................................... 31

Figure 3 – Test voltages ....................................................................................................... 42

Figure 4 – Across the groove ................................................................................................ 46

Figure 5 – Contour of the groove .......................................................................................... 47

Figure 6 – Contour of the groove with angle .......................................................................... 47

Figure 7 – Contour of rib ....................................................................................................... 47

Figure 8 – Uncemented joint with grooves less than X .......................................................... 48

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SIST EN IEC 60664-1:2020
IEC 60664-1:2020 © IEC 2020 – 5 –

Figure 9 – Uncemented joint with grooves equal to or more than X ....................................... 48

Figure 10 – Uncemented joint with a groove on one side less than X .................................... 49

Figure 11 – Creepage distance and clearance through an uncemented joint ......................... 49

Figure 12 – Creepage distance and clearance to a head of screw more than X ..................... 49

Figure 13 – Creepage distance and clearance to a head of screw less than X ....................... 50

Figure 14 – Creepage distance and clearance with conductive floating part .......................... 50

Figure A.1 – Withstand voltage at 2 000 m above sea level................................................... 53

Figure A.2 – Experimental data measured at approximately sea level and their low

limits for inhomogeneous field ............................................................................................... 54

Figure A.3 – Experimental data measured at approximately sea level and their low

limits for homogeneous field ................................................................................................. 55

Figure C.1 – Earthed test specimen ...................................................................................... 58

Figure C.2 – Unearthed test specimen .................................................................................. 59

Figure C.3 – Calibration for earthed test specimen................................................................ 62

Figure C.4 – Calibration for unearthed test specimen ............................................................ 62

Figure D.1 – Partial discharge test circuits ............................................................................ 64

Figure E.1 – Comparison between creepage distances specified in Table F.5 and

clearances in Table A.1 ........................................................................................................ 67

Figure G.1 – Determination of clearance distances according to 5.2 (1 of 2) ......................... 77

Figure H.1 – Determination of creepage distances according to 5.3 (1 of 2) .......................... 79

Table 1 – Dimensioning of grooves ....................................................................................... 46

Table A.1 – Withstand voltages for an altitude of 2 000 m above sea level (1 of 2) ............... 51

Table A.2 – Altitude correction factors for clearance correction ............................................. 52

Table B.1 – Inherent control or equivalent protective control ................................................. 56

Table B.2 – Cases where protective control is necessary and control is provided by

surge protective device having a ratio of voltage protection level to rated voltage not

smaller than that specified in IEC 61643 (all parts) ............................................................... 57

Table F.1 – Rated impulse withstand voltage for equipment energized directly from the

mains supply ......................................................................................................................... 68

Table F.2 – Clearances to withstand transient overvoltages .................................................. 69

Table F.3 – Single-phase three-wire or two-wire AC or DC systems ...................................... 70

Table F.4 – Three-phase four-wire or three-wire AC systems ................................................ 71

Table F.5 – Creepage distances to avoid failure due to tracking (1 of 2) ............................... 72

Table F.6 – Test voltages for verifying clearances only at different altitudes ......................... 74

Table F.7 – Severities for conditioning of solid insulation ...................................................... 74

Table F.8 – Dimensioning of clearances to withstand steady-state peak voltages,

temporary overvoltages or recurring peak voltages ........................................................... 75

Table F.9 – Additional information concerning the dimensioning of clearances to avoid

partial discharge ................................................................................................................... 75

Table F.10 – Altitude correction factors for clearance correction ........................................... 76

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SIST EN IEC 60664-1:2020
– 6 – IEC 60664-1:2020 © IEC 2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INSULATION COORDINATION FOR EQUIPMENT
WITHIN LOW-VOLTAGE SUPPLY SYSTEMS –
Part 1: Principles, requirements and tests
FOREWORD

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

all national electrotechnical committees (IEC National Committees). The object of IEC is to promote

international co-operation on all questions concerning standardization in the electrical and electronic fields. To

this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,

Technical Reports, Publicly Available Spec
...

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