Electromagnetic compatibility (EMC) - Part 3-12: Limits - Limits for harmonic currents produced by equipment connected to public low-voltage systems with input current >16 A and ≤ 75 A per phase

IEC 61000-3-12:2011 deals with the limitation of harmonic currents injected into the public supply system. The limits given in this International Standard are applicable to electrical and electronic equipment with a rated input current exceeding 16 A and up to and including 75 A per phase, intended to be connected to public low-voltage a.c. distribution systems of the following types:
- nominal voltage up to 240 V, single-phase, two or three wires;
- nominal voltage up to 690 V, three-phase, three or four wires;
- nominal frequency 50 Hz or 60 Hz. Other distribution systems are excluded. The limits given in this edition apply to equipment when connected to 230/400 V, 50 Hz systems. This standard applies to equipment intended to be connected to low-voltage systems interfacing with the public supply at the low-voltage level. It does not apply to equipment intended to be connected only to private low-voltage systems interfacing with the public supply only at the medium- or high-voltage level. This standard defines:
a) requirements and emission limits for equipment;
b) methods for type tests and simulations. Tests according to this International Standard are type tests of complete pieces of equipment. Conformity with this standard can also be determined by validated simulations. This second edition cancels and replaces the first edition published in 2004 and constitutes a technical revision. The significant technical changes with respect to the previous edition are:
- the replacement of the reference fundamental current I1 by the reference current Iref for the calculation of emission limits;
- a new added table of current emission limits (Table 5);
- a new added annex (Annex A) to define test conditions for some types of equipment;
- Deletion of the former Annexes B (Approximate interpolation formulas) and D (Information on the PWHD factor).

Compatibilité électromagnétique (CEM) - Partie 3-12: Limites - Limites pour les courants harmoniques produits par les appareils connectés aux réseaux publics basse tension ayant un courant appelé > 16 A et ≤ 75 A par phase

La CEI 61000-3-12:2011 traite de la limitation des courants harmoniques injectés dans le réseau public d'alimentation. Les limites définies dans la présente Norme internationale sont applicables aux appareils électriques et électroniques ayant un courant assigné d'entrée strictement supérieur à 16 A et inférieur ou égal à 75 A par phase, destinés à être connectés aux réseaux publics de distribution en courant alternatif basse tension des types suivants:
- tension nominale jusqu'à 240 V, monophasé, deux ou trois conducteurs;
- tension nominale jusqu'à 690 V, triphasé, trois ou quatre conducteurs;
- fréquence nominale 50 Hz ou 60 Hz. Les autres réseaux de distribution sont exclus. Les limites définies dans la présente édition s'appliquent aux appareils connectés aux réseaux 230/400 V, 50 Hz. La présente norme s'applique aux appareils destinés à être raccordés à des réseaux basse tension connectés au réseau public d'alimentation au niveau basse tension. Elle ne s'applique pas aux appareils destinés à être raccordés uniquement à des réseaux basse tension privés connectés au réseau public d'alimentation seulement au niveau moyenne ou haute tension. Cette norme définit:
- les exigences et limites d'émissions pour les appareils;
- les méthodes d'essai de type et de simulation. Les essais réalisés conformément à la présente Norme internationale sont des essais de type sur des équipements complets. La conformité à la présente norme peut également être déterminée au moyen de simulations validées. Cette deuxième édition annule et remplace la première édition publiée en 2004 et constitue une révision technique. Les principaux changements techniques par rapport à l'édition précédente sont les suivants:
- remplacement du courant fondamental de référence I1 par le courant de référence Iref pour le calcul des limites d'émission;
- ajout d'un nouveau tableau de limites de courant d'émission (Tableau 5);
- ajout d'une nouvelle annexe (Annexe A) définissant les conditions d'essai pour certains types de matériels;
- suppression des anciennes Annexes B (Formules d'interpolation approximatives) and D (Informations sur le facteur PWHD).

General Information

Status
Published
Publication Date
11-May-2011
Current Stage
PPUB - Publication issued
Start Date
12-May-2011
Completion Date
12-May-2011
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IEC 61000-3-12:2011 - Electromagnetic compatibility (EMC) - Part 3-12: Limits - Limits for harmonic currents produced by equipment connected to public low-voltage systems with input current >16 A and ≤ 75 A per phase
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IEC 61000-3-12
Edition 2.0 2011-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electromagnetic compatibility (EMC) –
Part 3-12: Limits – Limits for harmonic currents produced by equipment
connected to public low-voltage systems with input current >16 A and ≤75 A per
phase
Compatibilité électromagnétique (CEM) –
Partie 3-12: Limites – Limites pour les courants harmoniques produits par les
appareils connectés aux réseaux publics basse tension ayant un courant
appelé >16 A et ≤75 A par phase
IEC 61000-3-12:2011
---------------------- Page: 1 ----------------------
THIS PUBLICATION IS COPYRIGHT PROTECTED
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---------------------- Page: 2 ----------------------
IEC 61000-3-12
Edition 2.0 2011-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electromagnetic compatibility (EMC) –
Part 3-12: Limits – Limits for harmonic currents produced by equipment
connected to public low-voltage systems with input current >16 A and ≤75 A per
phase
Compatibilité électromagnétique (CEM) –
Partie 3-12: Limites – Limites pour les courants harmoniques produits par les
appareils connectés aux réseaux publics basse tension ayant un courant
appelé >16 A et ≤75 A par phase
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX U
ICS 33.100.10 ISBN 978-2-88912-486-2
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
SC 77A/Publication IEC 61000-3-12 (2011), Second edition/I-SH 01
ELECTROMAGNETIC COMPATIBILITY (EMC) –
Part 3-12: Limits –
Limits for harmonic currents produced by equipment connected to public
low-voltage systems with input current >16 A and ≤75 A per phase
INTERPRETATION SHEET
This interpretation sheet has been prepared by subcommittee 77A: Low frequency
phenomena, of IEC technical committee 77: Electromagnetic compatibility.
The text of this interpretation sheet is based on the following documents:
ISH Report on voting
77A/792/ISH 77A/800/RVD

Full information on the voting for the approval of this interpretation sheet can be found in the

report on voting indicated in the above table.
___________

Interpretation of requirements for equipment with unforeseen low input currents during

tests according to IEC 61000-3-12:2011: Electromagnetic compatibility (EMC) – Part 3-

12: Limits – Limits for harmonic currents produced by equipment connected to public

low-voltage systems with input current >16 A and ≤75 A per phase.

When equipment that has a rated current above 16 A draws a reference current that is less

than 16 A under the specified test conditions, the manufacturer may proceed in one of the

following ways:
1) Comply with the proportional limits as calculated, choosing the required R ;
sce

2) Comply with the absolute limits given in IEC 61000-3-2:2011, Table 1, using the

measurement procedure defined in 4.2.2 in IEC 61000-3-12:2011;

In that case, the manufacturer shall state in the instruction manual “Equipment complying

with IEC 61000-3-12”, without having to declare a minimum short circuit power S .

3) Change the test conditions to a representative 2,5 min period, as defined in IEC 61000-3-

12:2011, Table 1 for long cyclic equipment, and comply with the proportional limits as

calculated, choosing the required R .
sce

The manufacturer is strongly advised to state in the test report which of these ways was used,

so that subsequent tests are carried out with the same procedure.
September 2012 ICS 33.100.10 French text overleaf
---------------------- Page: 4 ----------------------
– 2 – 61000-3-12  IEC:2011
CONTENTS

FOREWORD ........................................................................................................................... 3

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

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

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

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

4 Measurement conditions ................................................................................................. 11

4.1 Determination of the reference current ................................................................... 11

4.2 Harmonic current measurement ............................................................................. 11

4.2.1 General ..................................................................................................... 11

4.2.2 Measurement procedure ............................................................................ 11

4.2.3 Repeatability .............................................................................................. 11

4.2.4 Starting and stopping ................................................................................. 12

4.2.5 Application of limits .................................................................................... 12

4.2.6 Test report ................................................................................................. 12

4.2.7 Test observation period.............................................................................. 12

4.3 Equipment consisting of several self-contained items ............................................. 12

5 Requirements and limits for equipment ........................................................................... 13

5.1 Control methods .................................................................................................... 13

5.2 Limits for emission ................................................................................................. 13

6 Product documentation ................................................................................................... 17

7 Test and simulation conditions ........................................................................................ 17

7.1 General ................................................................................................................. 17

7.2 Requirements for direct measurement ................................................................... 17

7.3 Requirements for simulation .................................................................................. 18

7.4 General conditions for test and simulation .............................................................. 19

Annex A (normative) Type test conditions ............................................................................. 21

Annex B (informative) Illustration of limits for harmonic currents ........................................... 23

Annex C (informative) Equipment not complying with the requirements and limits of this

standard ............................................................................................................................... 24

Bibliography .......................................................................................................................... 25

Figure 1 – Definition of the 5 harmonic current phase angle (I leads U , α > 0) .............. 10

5 p1 5

Figure 2 – Definition of the 5 harmonic current phase angle (I lags U , α < 0) ................ 10

5 p1 5

Figure 3 – Flowchart of the application procedure .................................................................. 16

Figure B.1 – Limits of the 5 harmonic current as functions of R ....................................... 23

sce

Table 1 – Values of the observation period ............................................................................ 12

Table 2 – Current emission limits for equipment other than balanced three-phase

equipment ............................................................................................................................. 15

Table 3 – Current emission limits for balanced three-phase equipment .................................. 15

Table 4 – Current emission limits for balanced three-phase equipment under specified

conditions (a, b, c) ................................................................................................................ 15

Table 5 – Current emission limits for balanced three-phase equipment under specified

conditions (d, e, f) ................................................................................................................. 16

---------------------- Page: 5 ----------------------
61000-3-12  IEC:2011 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTROMAGNETIC COMPATIBILITY (EMC) –
Part 3-12: Limits –
Limits for harmonic currents produced
by equipment connected to public low-voltage systems
with input current >16 A and ≤75 A per phase
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 liaising with the IEC also participate in this preparation. IEC collaborates closely

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

agreement between the two organizations.

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

consensus of opinion on the relevant subjects since each technical committee has representation from all

interested IEC National Committees.

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

Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

misinterpretation by any end user.

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

transparently to the maximum extent possible in their national and regional publications. Any divergence

between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in

the latter.

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

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

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

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

members of its technical committees and IEC National Committees for any personal injury, property damage or

other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

Publications.

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

indispensable for the correct application of this publication.

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

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

International Standard IEC 61000-3-12 has been prepared by subcommittee 77A: Low

frequency phenomena, of IEC technical committee 77: Electromagnetic compatibility.

This second edition cancels and replaces the first edition published in 2004 and constitutes a

technical revision.

The significant technical changes with respect to the previous edition are listed below:

– the reference fundamental current I is replaced by the reference current I for the

1 ref
calculation of emission limits;
– a new table of current emission limits (Table 5) is added;

– a new annex (Annex A) is added to define test conditions for some types of equipment;

---------------------- Page: 6 ----------------------
– 4 – 61000-3-12 © IEC:2011

• former Annexes B (Approximate interpolation formulas) and D (Information on the PWHD

factor) are deleted.
The text of this standard is based on the following documents:
FDIS Report on voting
77A/740/FDIS 77A/747/RVD

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

voting indicated in the above table.

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

A list of all parts of the IEC 61000 series, published under the general title Electromagnetic

compatibility (EMC), can be found on the IEC website.

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

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

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

The contents of the interpretation sheet 1 of September 2012 have been included in this copy.

---------------------- Page: 7 ----------------------
61000-3-12  IEC:2011 – 5 –
INTRODUCTION
IEC 61000 is published in separate parts according to the following structure:
Part 1: General
General considerations (introduction, fundamental principles)
Definitions, terminology
Part 2: Environment
Description of the environment
Classification of the environment
Compatibility levels
Part 3: Limits
Emission limits
Immunity limits

(in so far as they do not fall under the responsibility of the product committees)

Part 4: Testing and measurement techniques
Measurement techniques
Testing techniques
Part 5: Installation and mitigation guidelines
Installation guidelines
Mitigation methods and devices
Part 6: Generic standards
Part 9: Miscellaneous

Each part is further subdivided into several parts, published either as International Standards

or as technical specifications or technical reports, some of which have already been published

as sections. Others will be published with the part number followed by a dash and a second

number identifying the subdivision (example: IEC 61000-6-1).
This International Standard is a Product Family Standard.
---------------------- Page: 8 ----------------------
– 6 – 61000-3-12  IEC:2011
ELECTROMAGNETIC COMPATIBILITY (EMC) –
Part 3-12: Limits –
Limits for harmonic currents produced
by equipment connected to public low-voltage systems
with input current >16 A and ≤75 A per phase
1 Scope

This part of IEC 61000 deals with the limitation of harmonic currents injected into the public

supply system. The limits given in this International Standard are applicable to electrical and

electronic equipment with a rated input current exceeding 16 A and up to and including 75 A

per phase, intended to be connected to public low-voltage a.c. distribution systems of the

following types:
• nominal voltage up to 240 V, single-phase, two or three wires;
• nominal voltage up to 690 V, three-phase, three or four wires;
• nominal frequency 50 Hz or 60 Hz.

Other distribution systems are excluded. The limits given in this edition apply to equipment

when connected to 230/400 V, 50 Hz systems. See also Clause 5.

NOTE 1 The limits for the other systems will be added in a future edition of this standard.

NOTE 2 Equipment with a rated input current exceeding 75 A per phase should be considered in the harmonic

current requirements for installations. See IEC/TR 61000-3-6 and future IEC/TR 61000-3-14.

This standard applies to equipment intended to be connected to low-voltage systems

interfacing with the public supply at the low-voltage level. It does not apply to equipment

intended to be connected only to private low-voltage systems interfacing with the public supply

only at the medium- or high-voltage level.

NOTE 3 The scope of this standard is limited to equipment connected to public low voltage systems because

emissions from equipment installed in private low voltage systems can be controlled in aggregate at the MV point of

common coupling using procedures defined in IEC/TR 61000-3-6 and/or by means of contractual agreements

between the distribution network operator and the customer. It is expected that operators of private systems will

manage the EMC environment in a manner that ensures compliance with the provisions given in IEC/TR 61000-3-6

and/or the contractual agreements.

NOTE 4 If the equipment is intended to be connected only to private systems, the manufacturer should make this

very clear in the product documentation.

NOTE 5 Professional equipment with input current ≤16 A per phase and that does not comply with the

requirements and limits of standard IEC 61000-3-2 may be permitted to be connected to certain types of low voltage

supplies, in the same way as equipment with input current >16 A per phase and that does not comply with the

requirements and limits of the present standard (see Annex C).

NOTE 6 The limits in this standard are not applicable to stand-alone harmonic filters.

This standard defines:
a) requirements and emission limits for equipment;
b) methods for type tests and simulations.

Tests according to this International Standard are type tests of complete pieces of equipment.

Conformity with this standard can also be determined by validated simulations.
---------------------- Page: 9 ----------------------
61000-3-12  IEC:2011 – 7 –
2 Normative references

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.
IEC 60038, IEC standard voltages

IEC 60050(161):1990, International Electrotechnical Vocabulary – Chapter 161: Electro-

magnetic compatibility
Amendment 1 (1997)
Amendment 2 (1998)

IEC 61000-2-2, Electromagnetic compatibility (EMC) – Part 2-2: Environment – Compatibility

levels for low-frequency conducted disturbances and signalling in public low-voltage power

supply systems

IEC 61000-2-4, Electromagnetic compatibility (EMC) – Part 2-4: Environment – Compatibility

levels in industrial plants for low-frequency conducted disturbances

IEC 61000-3-2, Electromagnetic compatibility (EMC) – Part 3-2: Limits – Limits for harmonic

current emissions (equipment input current ≤16 A per phase)

IEC 61000-4-7, Electromagnetic compatibility (EMC) – Part 4-7: Testing and measurement

techniques – General guide on harmonics and interharmonics measurements and
instrumentation, for power supply systems and equipment connected thereto
3 Terms and definitions

For the purposes of this document, the definitions given in IEC 60050(161) and the following

definitions apply.
3.1
total harmonic current
THC
total r.m.s. value of the harmonic current components of orders 2 to 40
THC= I
h=2
3.2
partial weighted harmonic current
PWHC

total r.m.s. value of a selected group of higher order harmonic current components (in this

International Standard from order 14 to order 40), weighted with the harmonic order h

PWHC= h⋅ I
∑ h
h=14

NOTE The partial weighted harmonic current is employed in order to ensure that the effects of the higher order

harmonic currents on the results are reduced sufficiently and individual limits need not be specified.

---------------------- Page: 10 ----------------------
– 8 – 61000-3-12  IEC:2011
3.3
point of common coupling
PCC

point in the public system which is closest to the customer concerned and to which other

customers are or may be connected
3.4
single-phase equipment
equipment connected between one line conductor and the neutral conductor

NOTE This includes equipment in which separate loads are connected from one or more line conductors to the

neutral conductor
3.5
interphase equipment
equipment connected between two line conductors (phases)

NOTE The neutral conductor is not used as a current-carrying conductor under normal operating conditions.

3.6
three-phase equipment
equipment connected to the three line conductors

NOTE 1 The neutral conductor is not used as a current-carrying conductor under normal operating conditions.

NOTE 2 Equipment intended to be connected to all three phases and to the neutral and where the neutral

conductor is used as a current-carrying conductor, is considered as three separate single-phase items.

3.7
balanced three-phase equipment

three-phase equipment connected to the three line conductors of a three-phase supply and in

which the three line or phase currents are designed to be identical in amplitude and wave-

shape, each being displaced from the other two by one-third of a fundamental period

3.8
unbalanced three-phase equipment

three-phase equipment connected to the three line conductors of a three-phase supply and in

which the three line or phase currents are not designed to be identical in amplitude or wave-

shape, or the displacement between any two is other than one-third of a fundamental period

3.9
hybrid equipment

combination of a balanced three-phase load and one or more loads connected between phase

and neutral or between phases
3.10
short-circuit power

value of the three-phase short-circuit power calculated from the nominal interphase system

voltage U and the line impedance Z of the system at the PCC:
nominal
S = U / Z
sc nominal
where Z is the system impedance at the power frequency
3.11
rated apparent power of the equipment
equ

value calculated from the rated current I of the piece of equipment stated by the

equ

manufacturer and the rated voltage U (single phase) or U (interphase) as follows:

p i
---------------------- Page: 11 ----------------------
61000-3-12  IEC:2011 – 9 –
a) S = U I for single-phase equipment and the single-phase part of hybrid
equ p equ
equipment;
b) S = U I for interphase equipment;
equ i equ
c) S = 3 U I for balanced three-phase equipment and the three-phase part of
equ i equ
hybrid equipment;
d) S = 3 U I for unbalanced three-phase equipment, where I is the
equ i equ max equ max
maximum of the r.m.s. currents flowing in any one of the three
phases

NOTE In the case of a voltage range, U or U is a nominal system voltage according to IEC 60038 (for example:

p i
120 V or 230 V for single-phase or 400 V line-to-line for three-phase).
3.12
reference current
ref

value of the r.m.s. input current of the equipment determined according to 4.1 and used to

establish emission limits
3.13
rated current of the equipment
equ

input current of the piece of equipment as declared by the manufacturer and marked as such

on the rating plate of the piece of equipment or stated in the product documents
3.14
short-circuit ratio
sce
characteristic value of a piece of equipment defined as follows:
a) R = S / (3 S ) for single-phase equipment and the single-phase part of hybrid
sce sc equ
equipment;
b) R = S / (2 S ) for interphase equipment;
sce sc equ
c) R = S / S for all three-phase equipment and the three-phase part of hybrid
sce sc equ
equipment

NOTE 1 R may be related directly to basic known quantities by means of the equations:

sce

R = U/(√3 × Z × I ) for single-phase equipment and the single phase part of hybrid equipment;

sce equ
R = U/(2 × Z × I ) for interphase equipment;
sce equ

R = U/(√3 × Z × I ) for balanced three-phase equipment and the three-phase part of hybrid equipment;

sce equ
R = U/(√3 × Z × I ) for unbalanced three-phase equipment
sce equ max
where U = U , and is assumed to be equal to U or √3 × U , whichever is relevant.
nominal i p
NOTE 2 R is not the same as R , as defined in IEC 61000-2-6.
sce sc

NOTE 3 For hybrid equipment, the method of calculating a single R value is given in 5.2.

sce
3.15
stand-by mode

non-operational, low power consumption mode (usually indicated in some way on the

equipment) that can persist for an indefinite time
NOTE This mode is sometimes termed sleep mode.
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– 10 – 61000-3-12  IEC:2011
3.16
phase angle of I related to the fundamental phase-to-neutral voltage U
5 p1
phase angle of the 5 harmonic current determined as described in Figures 1 and 2
3.17
professional equipment

equipment for use in trades, professions, or industries and which is not intended for sale to the

general publ
...

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