SIST EN 60076-6:2008

Power transformers -- Part 6: Reactors

Applies to the following types of reactors: shunt reactors; series reactors including current-limiting reactors, neutral-earthing reactors, power flow control reactors, motor starting reactors, arc-furnace series reactors; filter (tuning) reactors; capacitor damping reactors; capacitor discharge reactors; earthing transformers (neutral couplers); arc-suppression reactors; smoothing reactors for HVDC and industrial application.

Leistungstransformatoren - Teil 6: Drosselspulen

Transformateurs de puissance -- Partie 6: Bobines d'inductance

S'applique aux types de bobines d'inductance suivants: bobines d'inductance shunt; bobines d'inductance série y compris les bobines d'inductance de limitation du courant, de mise à la terre du neutre, de commande de flux d'énergie, de démarrage des moteurs et les bobines d'inductance pour les fours à arc; bobines d'inductance de filtrage (d'accord); bobines d'inductance d'amortissement de condensateur; bobines d'inductance de décharge de condensateur; transformateurs de mise à la terre (connecteurs de neutre); bobines d'inductance d'extinction d'arc; bobines d'inductance de lissage pour application CCHT et industrielle.

Močnostni transformatorji - 6. del: Dušilke (IEC 60076-6:2007)

General Information

• Status: Published
• Publication Date: 16-Sep-2008
• ICS: 29.180 - Transformers. Reactors
• Technical Committee: ETR - Power transformers
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 03-Sep-2008
• Due Date: 08-Nov-2008
• Completion Date: 17-Sep-2008
• Ref Project: EN 60076-6:2008 - Power transformers - Part 6: Reactors

Relations

• Replaces: SIST EN 60289:1997/A11:2004 - Reactors
• Effective Date: 01-Dec-2008
• Replaces: SIST EN 60289:1997 - Reactors
• Effective Date: 01-Oct-2008
• Revised: SIST EN 60289:1997 - Reactors
• Effective Date: 07-Jun-2011
• Revised: SIST EN 60289:1997/A11:2004 - Reactors
• Effective Date: 07-Jun-2011

Standards Content (Sample)

SLOVENSKI STANDARD
01-oktober-2008
1DGRPHãþD
SIST EN 60289:1997
SIST EN 60289:1997/A11:2004
0RþQRVWQLWUDQVIRUPDWRUMLGHO'XãLONH,(&
Power transformers - Part 6: Reactors (IEC 60076-6:2007)
Leistungstransformatoren - Teil 6: Drosselspulen (IEC 60076-6:2007)
Transformateurs de puissance - Partie 6: Bobines d'inductance (CEI 60076-6:2007)
Ta slovenski standard je istoveten z: EN 60076-6:2008
ICS:
29.180 Transformatorji. Dušilke Transformers. Reactors
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 60076-6
NORME EUROPÉENNE
July 2008
EUROPÄISCHE NORM
ICS 29.180 Supersedes EN 60289:1994 + A11:2002

English version
Power transformers -
Part 6: Reactors
(IEC 60076-6:2007)
Transformateurs de puissance -  Leistungstransformatoren -
Partie 6: Bobines d'inductance Teil 6: Drosselspulen
(CEI 60076-6:2007) (IEC 60076-6:2007)

This European Standard was approved by CENELEC on 2008-06-01. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: rue de Stassart 35, B - 1050 Brussels

© 2008 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60076-6:2008 E
Foreword
The text of document 14/538/CDV, future edition 1 of IEC 60076-6, prepared by IEC TC 14, Power
transformers, was submitted to the IEC-CENELEC Parallel Unique Acceptance Procedure and was
approved by CENELEC as EN 60076-6 on 2008-06-01.
This European Standard supersedes EN 60289:1994 + A11:2002.
– wide extension of the “Definitions”, “Rating” and “Tests” clauses,
– more consequent distinction between definition and rating,
– “Tests” subclauses take into account the latest revisions of relevant EN 60076 standards,
– dielectric testing of reactors is now in line with dielectric testing of transformer according to
EN 60076-3:2001,
– consequent distinction between oil-immersed and dry-type reactor,
– document offers an easier handling and is a more stand-alone document than EN 60289,
– introduction of the discharge reactor as part of Clause 9,
– introduction of the turn-to-turn overvoltage test for dry-type reactors (Annex E),
– important background information given by newly introduced informative annexes,
– Annex A (informative) – Information on shunt reactor switching and on special applications
– Annex B (informative) – Magnetic characteristic of reactors
– Annex C (informative) – Mutual reactance, coupling factor and equivalent reactances of three-
phase reactors
– Annex D (informative) – Temperature correction of losses for liquid-immersed gapped-core and
magnetically shielded air-core reactors
– Annex F (informative) – Short-circuit testing
– Annex G (informative) – Resistors – Characteristics, specification and tests.
The following dates were fixed:

– latest date by which the EN has to be implemented

at national level by publication of an identical
(dop) 2009-03-01
national standard or by endorsement

– latest date by which the national standards conflicting
(dow) 2011-06-01
with the EN have to be withdrawn
Annex ZA has been added by CENELEC.
__________
- 3 - EN 60076-6:2008
Endorsement notice
The text of the International Standard IEC 60076-6:2007 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 60143 NOTE  Harmonized in EN 60143 series (not modified).
IEC 60168 NOTE  Harmonized as EN 60168:1994 (not modified)
+ A1:1997 (not modified) + A2:2000 (not modified).
IEC 60273 NOTE  Harmonized as HD 578 S1:1992 (not modified).
IEC 60529 NOTE  Harmonized as EN 60529:1991 (not modified).
IEC 60871-1 NOTE  Harmonized as EN 60871-1:2005 (not modified).
IEC 61378-1 NOTE  Harmonized as EN 61378-1:1998 (not modified).
IEC 61378-2 NOTE  Harmonized as EN 61378-2:2001 (not modified).
IEC 62271-110 NOTE  Harmonized as EN 62271-110:2005 (not modified).
__________
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application 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  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year

IEC 60060-1 1989 High-voltage test techniques -
+ corr. March 1990 Part 1: General definitions and test HD 588.1 S1 1991
requirements
IEC 60076-1 (mod) 1993 Power transformers - EN 60076-1 1997
A1 1999 Part 1: General A1 2000
+ A11 1997
+ A12 2002
IEC 60076-2 (mod) 1993 Power transformers - EN 60076-2 1997
Part 2: Temperature rise
IEC 60076-3 2000 Power transformers -
+ corr. December 2000 Part 3: Insulation levels, dielectric tests and EN 60076-3 2001
external clearances in air
IEC 60076-4 2002 Power transformers - EN 60076-4 2002
Part 4: Guide to the lightning impulse and
switching impulse testing - Power
transformers and reactors
IEC 60076-5 2006 Power transformers - EN 60076-5 2006
Part 5: Ability to withstand short circuit

IEC 60076-7 2005 Power transformers - - -
Part 7: Loading guide for oil-immersed power
transformers
IEC 60076-8 1997 Power transformers - - -
Part 8: Application guide
IEC 60076-10 2001 Power transformers - EN 60076-10 2001
Part 10: Determination of sound levels

IEC 60076-11 2004 Power transformers - EN 60076-11 2004
Part 11: Dry-type transformers

1) 2)
IEC 60137 - Insulated bushings for alternating voltages EN 60137 2003
above 1 000 V
1) 2)
IEC 60270 - High-voltage test techniques - Partial EN 60270 2001
discharge measurements
1) 2)
IEC 60721-2-6 - Classification of environmental conditions - HD 478.2.6 S1 1993
Part 2: Environmental conditions appearing in
nature - Earthquake vibration and shock

1)
IEC/TR 60815 - Guide for the selection of insulators in - -
respect of polluted conditions

1)
Undated reference.
2)
Valid edition at date of issue.

- 5 - EN 60076-6:2008
Publication Year Title EN/HD Year

IEC 60905 1987 Loading guide for dry-type power - -
transformers
IEC/TR3 60943 1998 Guidance concerning the permissible - -
temperature rise for parts of electrical
equipment, in particular for terminals

IEC 60076-6
Edition 1.0 2007-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Power transformers –
Part 6: Reactors
Transformateurs de puissance –
Partie 6: Bobines d’inductance

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XF
CODE PRIX
ICS 29.180 ISBN 2-8318-9507-3
– 2 – 60076-6 © IEC:2007
CONTENTS
FOREWORD.9
INTRODUCTION.11

1 Scope.12
2 Normative references .12
3 Terms and definitions .13
3.1 Types of reactor .13
3.2 Other definitions.14
4 Symbols and abbreviations.17
5 Service conditions .18
5.1 General .18
5.2 Seismic conditions .18
6 Design, testing, tolerances and application.18
7 Shunt reactors.20
7.1 General .20
7.2 Design.20
7.3 Terms and definitions .20
7.4 Rating .21
7.4.1 Rated voltage .22
7.4.2 Maximum operating voltage .22
7.4.3 Rated power .22
7.4.4 Zero-sequence reactance of a three-phase star-connected reactor.22
7.4.5 Mutual reactance of a three-phase reactor.22
7.4.6 Inrush current level.22
7.4.7 Linearity of the shunt reactor .22
7.5 Temperature rise.22
7.6 Insulation level .23
7.7 Rating plates .23
7.8 Tests.23
7.8.1 General .23
7.8.2 Routine tests .23
7.8.3 Type tests .24
7.8.4 Special tests.24
7.8.5 Determination of reactance and linearity of reactance.24
7.8.6 Measurement of loss (routine test, special test) .25
7.8.7 Measurement of harmonics of the current (special test) .26
7.8.8 Measurement of zero-sequence reactance on three-phase reactors
(special test).27
7.8.9 Measurement of mutual reactance on three-phase reactors (special
test).27
7.8.10 Dielectric tests.27
7.8.11 Measurement of magnetic characteristic (special test) .30
7.8.12 Measurement of acoustic sound level (type test, special test).30
7.8.13 Measurement of vibration (type test).31
7.8.14 Temperature rise test (type test).32
7.9 Tolerances .33

60076-6 © IEC:2007 – 3 –
7.9.1 General .33
7.9.2 Tolerances on reactance at rated voltage and rated frequency .33
7.9.3 Tolerances on the linearity of reactance .33
7.9.4 Tolerance on loss .33
8 Current-limiting reactors and neutral-earthing reactors .33
8.1 General .33
8.2 Design.34
8.3 Terms and definitions .34
8.4 Rating .36
8.4.1 Rated continuous current.36
8.4.2 Rated thermal short-circuit current.37
8.4.3 Rated thermal short-circuit current duration .37
8.4.4 Rated mechanical short-circuit current.37
8.4.5 Rated short-time current.37
8.4.6 Rated short-time current duration or duty-cycle .37
8.4.7 Coupling factor .38
8.4.8 Rated short-circuit impedance .38
8.4.9 Rated short-time impedance .39
8.4.10 Rated continuous impedance.39
8.5 Ability to withstand rated thermal and rated mechanical short-circuit current .39
8.6 Temperature rise.39
8.6.1 Temperature rise at rated continuous current .39
8.6.2 Temperature due to rated thermal short-circuit current and rated
short-time current loading.40
8.7 Insulation level .40
8.7.1 General .40
8.8 Rating plates .40
8.9 Tests.41
8.9.1 General .41
8.9.2 Routine tests .41
8.9.3 Type tests .41
8.9.4 Special tests.42
8.9.5 Measurement of impedance at rated continuous current (routine test) .42
8.9.6 Measurement of impedance at rated short-time current (routine test).43
8.9.7 Measurement of loss (routine test, special test) .43
8.9.8 Separate source a.c. withstand voltage test (routine test, special
test).44
8.9.9 Winding overvoltage test for current-limiting reactors (routine test).44
8.9.10 Winding overvoltage test for neutral-earthing reactors (routine test) .45
8.9.11 Temperature rise test at rated continuous current (type test) .45
8.9.12 Lightning impulse test for current-limiting reactors (type test) .46
8.9.13 Short-circuit current test (special test) .46
8.9.14 Measurement of acoustic sound level at rated continuous current
(special test).47
8.9.15 Vibration measurement at rated continuous current (special test) .47
8.9.16 Switching impulse test (special test) .48
8.9.17 Double-ended lightning impulse test (special test) .48
8.9.18 Measurement of coupling factor (special test).49
8.9.19 Wet winding overvoltage test (special test) .49

– 4 – 60076-6 © IEC:2007
8.9.20 Wet separate source a.c. withstand voltage test (special test) .49
8.9.21 Measurement of reactance of the winding in the case of gapped-core
and magnetically-shielded air-core reactors (special test).49
8.10 Tolerances .50
8.10.1 Tolerance on impedances of reactors without compensation for
mutual coupling .50
8.10.2 Tolerance on impedance of reactors with compensation for mutual
coupling.50
8.10.3 Tolerance on loss .50
9 Filter, damping and discharge reactors associated with capacitors .50
9.1 General .50
9.2 Design.51
9.3 Terms and definitions .51
9.4 Rating .53
9.4.1 Rated power frequency current.53
9.4.2 Rated current spectrum .53
9.4.3 Rated inrush current .54
9.4.4 Rated inrush frequency.54
9.4.5 Rated discharge current .54
9.4.6 Rated discharge frequency .54
9.4.7 Rated thermal short-circuit current.54
9.4.8 Rated thermal short-circuit current duration .54
9.4.9 Rated mechanical short-circuit current.55
9.4.10 Rated inductance.55
9.4.11 Quality factor.55
9.5 Ability to withstand rated thermal and rated mechanical short-circuit current .55
9.6 Ability to withstand inrush or discharge current.56
9.7 Temperature rise.56
9.7.1 Temperature rise at equivalent current at power frequency.56
9.7.2 Temperature due to rated thermal short-circuit current loading .56
9.8 Insulation level .56
9.8.1 General .56
9.8.2 Insulation requirements .56
9.9 Rating plates .57
9.10 Tests.57
9.10.1 General .57
9.10.2 Routine tests.58
9.10.3 Type tests .58
9.10.4 Special tests .58
9.10.5 Measurement of inductance (routine test, type test) .58
9.10.6 Measurement of loss and quality factor (routine test, type test) .59
9.10.7 Winding overvoltage test (routine test) .59
9.10.8 Temperature rise test at rated continuous current (type test).60
9.10.9 Lightning impulse test (type test).60
9.10.10 Short-circuit current test (special test) .60
9.10.11 Measurement of acoustic sound level at rated continuous current
(special test) .61
9.10.12 Separate source a.c. withstand voltage test (special test) .62
9.10.13 Inrush current withstand test (special test) .62
9.10.14 Discharge current test (special test) .63

60076-6 © IEC:2007 – 5 –
9.10.15 Modified short-circuit/discharge current test (special test) .63
9.10.16 Mechanical resonance test (special test) .63
9.11 Tolerances .63
9.11.1 Tolerance on rated inductance .63
9.11.2 Tolerance on measured loss and quality factor .63
10 Earthing transformers (neutral couplers).63
10.1 General .63
10.2 Design.64
10.3 Terms and definitions .64
10.4 Rating .66
10.4.1 Rated voltage .66
10.4.2 Maximum operating voltage .66
10.4.3 Rated zero-sequence impedance.66
10.4.4 Rated continuous neutral current .66
10.4.5 Rated short-time neutral current .67
10.4.6 Rated short-time neutral current duration.67
10.4.7 Rated voltage of the secondary winding.67
10.4.8 Further ratings for the combination of an earthing transformer and an
arc-suppression reactor .67
10.5 Ability to withstand the rated short-time neutral current .67
10.6 Temperature rise.68
10.6.1 Temperature rise at rated voltage, rated continuous neutral current
and rated power of the secondary winding.68
10.6.2 Temperature after rated short-time neutral current loading .68
10.7 Insulation level .68
10.8 Rating plates .68
10.9 Tests.69
10.9.1 General .69
10.9.2 Routine tests.69
10.9.3 Type tests .70
10.9.4 Special tests .70
10.9.5 Measurement of zero-sequence impedance (routine test).70
10.9.6 Temperature rise test (type test) .71
10.9.7 Dielectric tests (routine test, type test) .72
10.9.8 Demonstration of ability to withstand rated short-time neutral
current (special test) .72
10.9.9 Measurement of loss at rated continuous neutral current (special
test) .73
10.9.10 Measurement of neutral current with three-phase excitation under
single-phase fault condition (type test) .73
10.10 Tolerances .73
11 Arc-suppression reactors.74
11.1 General .74
11.2 Design.74
11.3 Terms and definitions .74
11.4 Rating .75
11.4.1 Rated voltage .75
11.4.2 Maximum continuous voltage.75
11.4.3 Rated current .75
11.4.4 Rated current duration.76

– 6 – 60076-6 © IEC:2007
11.4.5 Adjustment range .76
11.4.6 Auxiliary winding .76
11.4.7 Secondary winding .76
11.4.8 Linearity of the arc-suppression reactor.76
11.5 Temperature rise.76
11.6 Insulation level .77
11.7 Rating plates .77
11.8 Tests.77
11.8.1 General .77
11.8.2 Routine tests.78
11.8.3 Type tests .78
11.8.4 Special tests .78
11.8.5 Measurement of current at rated voltage (type test), measurement
of current (routine test).78
11.8.6 Measurement of no-load voltage of the auxiliary and secondary
windings (routine test) .78
11.8.7 Temperature rise test (type test) .79
11.8.8 Dielectric tests (routine test, type test) .79
11.8.9 Measurement of loss (special test) .79
11.8.10 Measurement of linearity (special test) .80
11.8.11 Measurement of acoustic sound level (special test).80
11.8.12 Endurance tests of the inductance regulation mechanism (special
test) .80
11.8.13 Demonstration of ability to withstand the dynamic effects of the
rated current (special test) .80
11.9 Tolerances .81
12 Smoothing reactors .81
12.1 General .81
12.2 Design.81
12.3 Terms and definitions .81
12.4 Rating .82
12.4.1 Rated voltage .82
12.4.2 Maximum operating voltage .82
12.4.3 Rated continuous direct current .83
12.4.4 Rated continuous current spectrum .83
12.4.5 Short-time overload current, current spectrum and current duration or
duty-cycle.83
12.4.6 Rated transient fault current .83
12.4.7 Rated incremental inductance.83
12.4.8 Linearity of the smoothing reactor.83
12.4.9 Additional requirements for reactors with directly liquid cooled
windings .83
12.5 Temperature rise.84
12.6 Insulation levels .84
12.6.1 Lightning impulse levels .84
12.6.2 Switching impulse levels.84
12.6.3 Separate source d.c. withstand voltage level .84
12.6.4 Polarity-reversal withstand voltage level .84
12.6.5 Separate source a.c. withstand voltage level .84
12.7 Rating plates .85

60076-6 © IEC:2007 – 7 –
12.8 Tests.85
12.8.1 General .85
12.8.2 Routine tests.85
12.8.3 Type test .86
12.8.4 Special tests .86
12.8.5 Measurement of incremental inductance (routine test).86
12.8.6 Measurement of the harmonic current loss and calculation of the
total loss (routine test).87
12.8.7 Separate source a.c. withstand voltage test (routine test).88
12.8.8 Separate source d.c. withstand voltage test for liquid-immersed
reactors (routine test).88
12.8.9 Polarity-reversal withstand test for liquid-immersed reactors
(routine test) .89
12.8.10 Lightning impulse test (routine test).90
12.8.11 Switching impulse test (routine test, type test).90
12.8.12 Wet separate source d.c. withstand voltage test for dry-type
reactors (type test) .90
12.8.13 Temperature rise test (type test) .90
12.8.14 Measurement of acoustic sound level (special test).91
12.8.15 Measurement of high frequency impedance (special test).92
12.8.16 Test of the tightness of the liquid cooling circuit for reactors with
directly liquid cooled windings (routine test) .92
12.8.17 Measurement of the pressure drop for reactors with directly liquid
cooled windings (type test).93
12.8.18 Transient fault current test (special test) .93
12.8.19 Chopped wave impulse test for liquid-immersed reactors (special
test) .94
12.9 Tolerances .94

Annex A (informative) Information on shunt reactor switching and on special
applications .95
Annex B (informative) Magnetic characteristic of reactors .98
Annex C (informative) Mutual reactance, coupling factor and equivalent reactances of
three-phase reactors.105
Annex D (informative) Temperature correction of losses for liquid-immersed gapped-
core and magnetically-shielded air-core reactors . 108
Annex E (normative) Turn-to-turn overvoltage test for dry-type reactors. 110
Annex F (informative) Short-circuit testing .112
Annex G (informative) Resistors – Characteristics, specification and tests. 114

Bibliography.117

Figure 1 – Types of magnetic characteristics for reactors .15
Figure 2 – Parameters for non-linear magnetic characteristic.16
Figure 3 – Measurement of mutual reactance for three-phase reactors or banks of
three single-phase reactors .27
Figure 4 – Phase-to-earth test circuit for single-phase excitation .29
Figure 5 – Phase-to-phase test circuit for single-phase excitation .29

– 8 – 60076-6 © IEC:2007
Figure 6 – Single-phase excitation circuit for reactors with magnetic shield for zero-
sequence flux .29
Figure 7 – Measurement of mutual reactance for three-phase reactors or banks of
three single-phase reactors .49
Figure 8 – Single-phase fault test circuit with earthed neutral .73
Figure 9 – Single-phase fault test circuit with earthed voltage-supply.73
Figure 10 – Measuring circuit for determining incremental inductance of two identical
smoothing reactors .87
Figure 11 – Double reversal test voltage profile .89
Figure B.1 – Illustration of linked flux and current waveshapes with a sinusoidal
voltage applied to a reactor with a non-linear magnetic characteristic according to
Figure B.6.99
Figure B.2 – Circuit for measurement the magnetic characteristic according to B.7.1. 102
Figure B.3 – Equivalent circuit with the reactor short-circuited .102
Figure B.4 – Measured curves of a reactors d.c. charge and discharge current. 103
Figure B.5 – Calculated linked flux during discharge period (see equations B7 and B9) . 104
Figure B.6 – Magnetic characteristic .104
Figure C.1 – Equivalent scheme of a three-phase reactor including the magnetic
coupling between phases.105
Figure E.1 – Test circuit for turn-to-turn overvoltage test and sample oscillograms . 111

Table 1 – Temperature limits for winding terminals of dry-type reactors .19
Table 2 – Tolerances .74
Table 3 – Tolerances .81
Table C.1 – Reactance and flux ratios for reactors with uniform magnetic coupling. 106
Table C.2 – Coupling values for reactors with non-uniform magnetic coupling . 107

60076-6 © IEC:2007 – 9 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
POWER TRANSFORMERS –
Part 6: Reactors
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 Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations l
...