Electromagnetic compatibility (EMC) - Part 3-5: Limits - Limitation of voltage fluctuations and flicker in low-voltage power supply systems for equipment with rated current greater than 75 A

IEC/TS 61000-3-5:2009 deals with emission of disturbances due to voltage fluctuations and flicker. The recommendations in this Technical Specification are applicable to electrical and electronic equipment that has a rated input current exceeding 75 A per phase and is intended to be connected to a public low-voltage a.c. distribution system. Recommendations that specify information enabling a supply authority, manufacturer, or consumer to assess equipment are given in Annex A. This second edition cancels and replaces IEC 61000-3-5, published as Technical Report type 2 in 1994 and constitutes a technical revision. It includes the following significant technical changes with respect to the previous edition: the whole document and the title have been modified to eliminate any conflict with the published IEC 61000-3-11. The contents of the corrigenda of September 2009 and May 2010 have been included in this copy.

Compatibilité électromagnétique (CEM) - Partie 3-5: Limites - Limitation des fluctuations de tension et du flicker dans les réseaux basse tension pour les équipements ayant un courant appelé supérieur à 75 A

La CEI/TS 61000-3-5:2009 porte sur l'émission de perturbations de type fluctuations de tension et papillotement. Les recommandations figurant dans cette Spécification Technique sont applicables aux appareils électriques et électroniques dont le courant assigné d'entrée est supérieur à 75 A par phase et qui sont destinés à être raccordés à un réseau public de distribution basse tension. Les recommandations qui précisent les informations nécessaires pour permettre à une compagnie d'électricité, un constructeur ou un consommateur d'évaluer un matériel sont données dans l'Annexe A. Cette deuxième édition annule et remplace la CEI 61000-3-5, publiée comme Rapport Technique de type 2 en 1994 et constitue une révision technique. Elle inclut les modifications techniques majeures suivantes par rapport à l'édition précédente: le document dans son ensemble et le titre ont été modifiés pour éliminer tout conflit avec la CEI 61000-3-11 publiée. Le contenu des corrigenda de septembre 2009 et mai 2010 a été pris en considération dans cet exemplaire.

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Publication Date
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IEC TS 61000-3-5:2009 - Electromagnetic compatibility (EMC) - Part 3-5: Limits - Limitation of voltage fluctuations and flicker in low-voltage power supply systems for equipment with rated current greater than 75 A
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IEC/TS 61000-3-5
Edition 2.0 2009-07
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
Electromagnetic compatibility (EMC) –
Part 3-5: Limits – Limitation of voltage fluctuations and flicker in low-voltage
power supply systems for equipment with rated current greater than 75 A
Compatibilité électromagnétique (CEM) –

Partie 3-5: Limites – Limitation des fluctuations de tension et du flicker dans les

réseaux basse tension pour les équipements ayant un courant appelé supérieur
à 75 A
IEC/TS 61000-3-5:2009
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC/TS 61000-3-5
Edition 2.0 2009-07
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
Electromagnetic compatibility (EMC) –
Part 3-5: Limits – Limitation of voltage fluctuations and flicker in low-voltage
power supply systems for equipment with rated current greater than 75 A
Compatibilité électromagnétique (CEM) –

Partie 3-5: Limites – Limitation des fluctuations de tension et du flicker dans les

réseaux basse tension pour les équipements ayant un courant appelé supérieur
à 75 A
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX
ICS 33.100.10 ISBN 978-2-88910-371-3
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – TS 61000-3-5 © IEC:2009
CONTENTS

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

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

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

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

3 Terms and definitions .......................................................................................................6

4 Equipment assessment.....................................................................................................6

4.1 General ...................................................................................................................6

4.2 Information from a consumer...................................................................................7

4.3 Evaluation of equipment with a rated input current exceeding 75 A per phase .........7

5 Recommended voltage change and flicker limits...............................................................7

5.1 Recommended voltage change limits.......................................................................7

5.2 Recommended flicker limits.....................................................................................8

Annex A (informative) Questionnaire to facilitate an accurate evaluation of flicker

emissions ...............................................................................................................................9

Annex B (informative) Explanation of 5.2 .............................................................................11

---------------------- Page: 4 ----------------------
TS 61000-3-5 © IEC:2009 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTROMAGNETIC COMPATIBILITY (EMC) –
Part 3-5: Limits –
Limitation of voltage fluctuations and
flicker in low-voltage power supply systems for
equipment with rated current greater than 75 A
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

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• the subject is still under technical development or where, for any other reason, there is the

future but no immediate possibility of an agreement on an International Standard.

Technical specifications are subject to review within three years of publication to decide

whether they can be transformed into International Standards.

IEC/TS 61000-3-5, which is a technical specification, has been prepared by subcommittee

77A: Low frequency phenomena of IEC technical committee 77: Electromagnetic compatibility.

---------------------- Page: 5 ----------------------
– 4 – TS 61000-3-5 © IEC:2009

This second edition cancels and replaces IEC 61000-3-5, published as Technical Report

type 2 in 1994 and constitutes a technical revision.

It includes the following significant technical changes with respect to the previous edition: the

whole document and the title have been modified to eliminate any conflict with the published

IEC 61000-3-11.
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
77A/681/DTS 77A/693/RVC

Full information on the voting for the approval of this technical specification 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.

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

the maintenance result 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

• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

The contents of the corrigenda of September 2009 and May 2010 have been included in this

copy.
---------------------- Page: 6 ----------------------
TS 61000-3-5 © IEC:2009 – 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 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: 61000-6-1).
IEC/TS 61000-3-5

This Technical Specification is presented as an informative document as it is already a

requirement, in most countries, for equipment having a rated input current exceeding 75 A per

phase to be subject to assessment and connection by the public supply network operator.

Therefore, it is not intended, at the time of publication, to be converted into an International

Standard.
---------------------- Page: 7 ----------------------
– 6 – TS 61000-3-5 © IEC:2009
ELECTROMAGNETIC COMPATIBILITY (EMC) –
Part 3-5: Limits –
Limitation of voltage fluctuations and
flicker in low-voltage power supply systems for
equipment with rated current greater than 75 A
1 Scope

This part of IEC 61000 deals with emission of disturbances due to voltage fluctuations and

flicker.

The recommendations in this Technical Specification are applicable to electrical and

electronic equipment that has a rated input current exceeding 75 A per phase and is intended

to be connected to a public low-voltage a.c. distribution system.

Recommendations that specify information enabling a supply authority, manufacturer, or

consumer to assess equipment are given in Annex A.
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 60050(161), International Electrotechnical Vocabulary – Chapter 161: Electromagnetic

compatibility

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

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

IEC 61000-3-3, Electromagnetic compatibility (EMC) – Part 3-3: Limits – Limitation of voltage

changes, voltage fluctuations and flicker in public low-voltage supply systems, for equipment

with rated current ≤16 A per phase and not subject to conditional connection

IEC 61000-3-11:2000, Electromagnetic compatibility (EMC) – Part 3-11: Limits – Limitation of

voltage changes, voltage fluctuations and flicker in public low-voltage supply systems -

Equipment with rated current ≤75 A and subject to conditional connection
3 Terms and definitions

For the purposes of this document the terms and definitions of IEC 61000-3-2, IEC 61000-3-3,

IEC 61000-3-11 and IEC 60050(161) apply.
4 Equipment assessment
4.1 General

Methods of flicker assessment for different types of voltage fluctuations are described in

IEC 61000-3-3 and IEC 61000-3-11.
---------------------- Page: 8 ----------------------
TS 61000-3-5 © IEC:2009 – 7 –

It is recommended that the disturbance levels present in the electricity supply are measured

before and after the connection of a new load which is critical in any respect. The assessment

method and data used should be verified.

An item of equipment having a rated input-current exceeding 75 A per phase, should comply

with the limits for all relevant phase-to-neutral voltages given in Clause 5.
4.2 Information from a consumer

When a consumer enquires about connection of a major load to a low voltage public supply

network he should, on request, provide information to enable assessment of the possible

disturbances caused by the load, otherwise connection may be refused.

The basic information to facilitate the assessment of equipment is recommended in the

questionnaire contained in Annex A. This questionnaire should be completed by the user, or

his authorized installation engineer, when connections of electrical loads to low-voltage public

power supply networks require special authorization.

The completed questionnaire should be given to the electricity supplier well in advance of

purchase and installation of the equipment to be connected.
4.3 Evaluation of equipment with a rated input current exceeding 75 A per phase

For equipment with a rated input current exceeding 75 A, a detailed system study is

recommended in order to facilitate conditional connection.

The equipment should be evaluated against the actual system impedance. It is recommended

that IEC 61000-3-3 and IEC 61000-3-11 voltage change limits for d and d , given in

max c
Clause 5, are applied.
5 Recommended voltage change and flicker limits
5.1 Recommended voltage change limits

The following limits are recommended to be applicable to equipment having ratings greater

than 75 A per phase:
• the relative steady state voltage change, d , should not exceed 3,3 %;
• the maximum relative voltage change, d , should not exceed
max
a) 4 % without additional conditions;

b) 6 % for equipment with automatic switching more than twice per day and that has a

delayed restart (the order of magnitude of the delay being of a few minutes) or that has

manual restart after power supply interruption;

NOTE The cycling frequency is further limited by the P and P limit. For example: a d of 6 % with

max
st lt

rectangular voltage change characteristic twice per hour gives a P of about 0,65.

c) 7 % for equipment which is attended whilst in use, or is switched on automatically, or

is intended to be switched on manually no more than twice per day and has a delayed

restart (the delay being not less than a few tens of seconds) or manual restart after a

power supply interruption.

In the case of equipment incorporating multiple loads, limits b) and c) should only apply if

there is delayed or manual restart after a power supply interruption. For all equipment with

automatic switching, that is energised immediately on restoration of supply after a power

supply interruption, a) should apply. For all equipment with manual switching, limits b) or c)

should apply, depending on the rate of switching.
---------------------- Page: 9 ----------------------
– 8 – TS 61000-3-5 © IEC:2009

P and P requirements should not be applicable to voltage changes caused by manual

st lt
switching.

The limits should not be applicable to emergency switching or emergency interruptions.

5.2 Recommended flicker limits

The recommended limit of P for a particular item of equipment is calculated by application of

Equation (1):
1/ 3
P =()S /S Equation (1)
st_LIMIT L TR
within the range 0,6 < P < 1.

NOTE 1 All P values that are calculated by application of Equation (1), and are less than 0,6, should be

st_LIMIT
set to 0,6.
where
S is the rated apparent power of the load to be connected, and
S is the rated apparent power of the feeding MV/LV transformer.
NOTE 2 P and P are defined in IEC 61000-3-3.
st lt

The recommended limit of P for a particular item of equipment is determined by Equation (2):

1/ 3
P = 0,65 S /S Equation (2)
lt_LIMIT L TR
i.e. P = 0,65 P
lt_LIMIT st_LIMIT

NOTE 3 The calculated flicker limits are recommended values, as the existing flicker level in the associated MV

network, the compatibility level of the low-voltage network and any existing utility regulations should be taken into

account.
---------------------- Page: 10 ----------------------
TS 61000-3-5 © IEC:2009 – 9 –
Annex A
(informative)
Questionnaire to facilitate an accurate
evaluation of flicker emissions
A.1 Main purpose of the equipment
Concise description of the equipment:
Type of equipment, with estimated mechanical and thermal ratings, as applicable.
A.2 Electrical characteristics of the equipment
A.2.1 Rating
Voltage .. . …
Number of phases .........................................
Apparent power rating…………………………
Power factor ... ………...
Starting current ..............................................
Power factor during start………………………
Rating of the largest motor …………………...
Largest switched thermal load ……………....
Capacitive load ………..... ……………………
Maximum permissible system impedance
to give compliance with the limits in Clause 5.…………….

The largest production of harmonics should be specified in amperes for each harmonic in an

appendix. For linear loads, this information is not necessary.
A.2.2 Effect on supply quality

Does the proposed load have any other characteristics, which could affect the supply quality?

In particular
a) Does it produce transients? YES NO
b) Does it produce voltage unbalance? YES NO
c) Does it produce a d.c. component in the supply? YES NO
d) Does it produce commutation notches, or extra zero crossings? YES NO
e) Does it produce harmonics, or other frequencies?
YES NO
---------------------- Page: 11 ----------------------
– 10 – TS 61000-3-5 © IEC:2009

f) Does it inject any frequencies into the supply system for signalling purposes? YES NO

g) Can the equipment generate back into the supply system?
YES NO
A.3 Work cycle

If the equipment has a varying load, the variation should be described generally (that is step

or sinusoidal) and in detailed terms (that is depth and rate of occurrence), together with any

information of value in the assessment of possible disturbance to the power supply.

Are the electric motors working with constant or varying torque?
If the torque is variable, state the variation frequency ...
Number of starts per day/per hour ...
Max. load ... . _... kVA
Min. load ... ... _.. kVA
Typical load variation frequency:

Time of the day at which switching, motor starts, or major variations of load are performed:

Type of power control:
A.4 limitation
Disturbance

Measures taken to limit disturbances caused by the equipment should be specified.

A.5 Compliance with standards and rules

The equipment manufacturer may specify any standards and rules for electrical disturbances

with which the equipment complies.
If requested, copies of test records should be submitted.
A.6 References

The consumer may give references to previous installations of the same type of equipment.

This information may be obtained from the equipment manufacturer.
---------------------- Page: 12 ----------------------
TS 61000-3-5 © IEC:2009 – 11 –
Annex B
(informative)
Explanation of 5.2

The established custom, on which the assessment method is based, was adopted so that the

emission of equipment having a rated power of S is allowed to increase as S approaches the

L L

rated power, S , of the supply transformer associated with the equipment. Where a piece of

equipment takes all the transformer power, it may be allowed to produce a flicker P = 1. This

approach, in conjunction with the superposition cube law, is expressed by the equation given

in 5.2.
The sum of the power of all loads should not exceed the transformer rating:
∑ (S / S ) ≤ 1
i L TR i
The superimposed flicker of all loads should not exceed the P limit:
3 1/3
[∑ (P ) ] ≤ P
st i st LIMIT
1/3
Both equations are satisfied if P is set to (S /S ) as in 5.2.
st.i L TR i

It can be seen from the equation in 5.2 that it is not necessary to limit flicker to less than 0,6.

The S /S ratio corresponding to the lowest flicker limit of 0,6 is given by
L TR
S /S = 0,6 = 0,216
L TR

For example, a load of 50 kVA associated with a 250 kVA transformer has a flicker

limit of 0,6.
___________
---------------------- Page: 13 ----------------------
– 12 – TS 61000-3-5 © CEI:2009
SOMMAIRE

AVANT-PROPOS..................................................................................................................13

INTRODUCTION...................................................................................................................15

1 Domaine d’application ....................................................................................................16

2 Références normatives...................................................................................................16

3 Termes et définitions ......................................................................................................16

4 Evaluation de l’appareil ..................................................................................................17

4.1 Généralités............................................................................................................17

4.2 Informations données par le consommateur ..........................................................17

4.3 Evaluation d’un matériel de courant assigné d’entrée supérieur à 75 A par

phase ....................................................................................................................17

5 Limites recommandées pour les variations de tension et le papillotement.......................17

5.1 Limites recommandées pour les variations de tension ...........................................17

5.2 Limites de papillotement recommandées ...............................................................18

Annexe A (informative) Questionnaire pour faciliter une évaluation précise des

émissions de papillotement...................................................................................................19

Annexe B (informative) Explications du 5.2 ..........................................................................21

---------------------- Page: 14 ----------------------
TS 61000-3-5 © CEI:2009 – 13 –
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
COMPATIBILITÉ ÉLECTROMAGNÉTIQUE (CEM) –
Partie 3-5: Limites –
Limitation des fluctuations de tension
et du flicker dans les réseaux basse tension pour
les équipements ayant un courant appelé supérieur à 75 A
AVANT-PROPOS

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domaines de l'électricité et de l'électronique. A cet effet, la CEI – entre autres activités – publie des Normes

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