IEC 61557-7:2019
(Main)Electrical safety in low voltage distribution systems up to 1 000 V AC and 1 500 V DC - Equipment for testing, measuring or monitoring of protective measures - Part 7: Phase sequence
Electrical safety in low voltage distribution systems up to 1 000 V AC and 1 500 V DC - Equipment for testing, measuring or monitoring of protective measures - Part 7: Phase sequence
IEC 61557-7:2019 is available as IEC 61557-7:2019 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 61557-7:2019 specifies the requirements applicable to measuring equipment for testing the phase sequence in three-phase distribution systems. Indication of the phase sequence can be mechanical, visual and/or audible. This document does not apply to additional measurements for other quantities. It does not apply to monitoring relays. IEC 61557-7:2019 cancels and replaces the second edition published in 2007. This edition constitutes a technical revision. This edition includes the following changes with respect to the previous edition:
a) alignment of the structure with that of the whole IEC 61557 series;
b) updated requirements in 4.3 in accordance with new editions of IEC 61010-1 and IEC 61010-031;
c) the information on markings was extended;
d) the information on the operating instructions was extended;
e) complement to the information on the testing of leads;
f) test leads for insulated conductors were introduced;
g) Annex B was added with information on phase sequence tests and indications.
Sécurité électrique dans les réseaux de distribution basse tension au plus égale à 1 000 V c.a. et 1 500 V c.c. - Dispositifs de contrôle, de mesure ou de surveillance de mesures de protection - Partie 7: Ordre de phases
IEC 61557-7:2019 est disponible sous forme de IEC 61557-7:2019 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.L'IEC 61557-7:2019 spécifie les exigences applicables aux appareils de mesure destinés à soumettre à essai l'ordre des phases dans les réseaux de distribution triphasés. L'indication de l'ordre des phases peut être mécanique, visuelle et/ou audible. Le présent document ne s'applique pas aux mesures supplémentaires destinées à d'autres grandeurs. Elle ne s'applique pas aux relais de surveillance. L'IEC 61557-7:2019 annule et remplace la deuxième édition parue en 2007. Cette édition constitue une révision technique. Cette édition inclut les modifications majeures suivantes par rapport à l'édition précédente:
a) alignement de la structure sur l'ensemble de la série IEC 61557;
b) mise à jour des exigences définies au 4.3 par rapport aux nouvelles éditions de l'IEC 61010-1 et de l'IEC 61010-031;
c) développement des informations concernant le marquage;
d) développement des informations concernant les instructions de fonctionnement;
e) développement des informations concernant les essais des câbles;
f) les câbles d'essai pour conducteurs isolés ont été introduits;
g) l'Annexe B a été ajouté avec information sur l'essai d'ordre de phases et indication d'ordre de phases.
General Information
Relations
Buy Standard
Standards Content (Sample)
IEC 61557-7
®
Edition 3.1 2023-08
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electrical safety in low voltage distribution systems up to 1 000 V AC and
1 500 V DC – Equipment for testing, measuring or monitoring of protective
measures –
Part 7: Phase sequence
Sécurité électrique dans les réseaux de distribution basse tension au plus égale
à 1 000 V en courant alternatif et 1 500 V en courant continu – Dispositifs de
contrôle, de mesure ou de surveillance de mesures de protection –
Partie 7: Ordre de phases
IEC 61557-7:2019-07+AMD1:2023-08 CSV(en-fr)
---------------------- Page: 1 ----------------------
THIS PUBLICATION IS COPYRIGHT PROTECTED
Copyright © 2023 IEC, Geneva, Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.
Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite ni
utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et
les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.
IEC Secretariat Tel.: +41 22 919 02 11
3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.
About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.
IEC publications search - webstore.iec.ch/advsearchform IEC Products & Services Portal - products.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews. With a subscription you will always have
committee, …). It also gives information on projects, replaced access to up to date content tailored to your needs.
and withdrawn publications.
Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
The world's leading online dictionary on electrotechnology,
Stay up to date on all new IEC publications. Just Published
containing more than 22 300 terminological entries in English
details all new publications released. Available online and once
and French, with equivalent terms in 19 additional languages.
a month by email.
Also known as the International Electrotechnical Vocabulary
(IEV) online.
IEC Customer Service Centre - webstore.iec.ch/csc
If you wish to give us your feedback on this publication or need
further assistance, please contact the Customer Service
Centre: sales@iec.ch.
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.
A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.
Recherche de publications IEC - Découvrez notre puissant moteur de recherche et consultez
webstore.iec.ch/advsearchform gratuitement tous les aperçus des publications. Avec un
La recherche avancée permet de trouver des publications IEC abonnement, vous aurez toujours accès à un contenu à jour
en utilisant différents critères (numéro de référence, texte, adapté à vos besoins.
comité d’études, …). Elle donne aussi des informations sur les
projets et les publications remplacées ou retirées. Electropedia - www.electropedia.org
Le premier dictionnaire d'électrotechnologie en ligne au monde,
IEC Just Published - webstore.iec.ch/justpublished
avec plus de 22 300 articles terminologiques en anglais et en
Restez informé sur les nouvelles publications IEC. Just
français, ainsi que les termes équivalents dans 19 langues
Published détaille les nouvelles publications parues.
additionnelles. Egalement appelé Vocabulaire
Disponible en ligne et une fois par mois par email.
Electrotechnique International (IEV) en ligne.
Service Clients - webstore.iec.ch/csc
Si vous désirez nous donner des commentaires sur cette
publication ou si vous avez des questions contactez-nous:
sales@iec.ch.
IEC Products & Services Portal - products.iec.ch
---------------------- Page: 2 ----------------------
IEC 61557-7
®
Edition 3.1 2023-08
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electrical safety in low voltage distribution systems up to 1 000 V AC and
1 500 V DC – Equipment for testing, measuring or monitoring of protective
measures –
Part 7: Phase sequence
Sécurité électrique dans les réseaux de distribution basse tension au plus égale
à 1 000 V en courant alternatif et 1 500 V en courant continu – Dispositifs de
contrôle, de mesure ou de surveillance de mesures de protection –
Partie 7: Ordre de phases
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.220.20, 29.080.01, 29.240.01 ISBN 978-2-8322-7453-8
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: 3 ----------------------
IEC 61557-7
®
Edition 3.1 2023-08
CONSOLIDATED VERSION
REDLINE VERSION
VERSION REDLINE
colour
inside
Electrical safety in low voltage distribution systems up to 1 000 V AC and
1 500 V DC – Equipment for testing, measuring or monitoring of protective
measures –
Part 7: Phase sequence
Sécurité électrique dans les réseaux de distribution basse tension au plus égale
à 1 000 V en courant alternatif et 1 500 V en courant continu – Dispositifs de
contrôle, de mesure ou de surveillance de mesures de protection –
Partie 7: Ordre de phases
IEC 61557-7:2019-07+AMD1:2023-08 CSV(en-fr)
---------------------- Page: 4 ----------------------
– 2 – IEC 61557-7:2019+AMD1:2023 CSV
© IEC 2023
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Requirements . 6
4.1 General . 6
4.2 Indication . 6
4.3 Measuring equipment . 7
4.3.1 General . 7
4.3.2 Portable phase sequence indicator . 7
4.3.3 Test leads for direct contact with live parts and accessories . 7
4.3.4 Test clips for non-contact phase detection . 8
5 Marking and operating instructions . 8
5.1 Marking . 8
5.2 Operating instructions . 8
6 Tests . 8
6.1 General . 8
6.1.1 Tests – General . 8
6.1.2 Visual display . 8
6.1.3 Audible indication (if applicable) . 8
6.2 Leakage current . 9
6.3 Test of mechanical requirements (type tests) . 9
6.3.1 Mechanical shock test . 9
6.3.2 Test of leads for direct contact with live parts . 10
6.3.3 Test of clips for non-contact phase detection . 10
6.4 Overvoltage . 10
6.5 Test of markings . 10
Annex A (normative) Illustrations for mechanical tests . 11
Annex B (informative) Phase sequence test . 13
B.1 Phase sequence test – Tripolar connection . 13
B.2 Phase sequence test – Sequential bipolar connection . 13
Bibliography . 15
Figure 1 – Test set-up for measurement of perceptibility of the audible indication . 9
Figure A.1 – Mechanical shock test . 11
Figure A.2 – Drop test . 12
Figure B.1 – Tripolar connection . 13
Figure B.2 – Sequential bipolar connection . 14
---------------------- Page: 5 ----------------------
IEC 61557-7:2019+AMD1:2023 CSV – 3 –
© IEC 2023
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL SAFETY IN LOW VOLTAGE DISTRIBUTION SYSTEMS
UP TO 1 000 V AC AND 1 500 V DC –
EQUIPMENT FOR TESTING, MEASURING OR MONITORING
OF PROTECTIVE MEASURES –
Part 7: Phase sequence
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.
This consolidated version of the official IEC Standard and its amendment has been
prepared for user convenience.
IEC 61557-7 edition 3.1 contains the third edition (201-07) [documents 85/683/FDIS and
85/698/RVD] and its amendment 1 (2023-08) [documents 85/872/FDIS and 85/882/RVD].
In this Redline version, a vertical line in the margin shows where the technical content
is modified by amendment 1. Additions are in green text, deletions are in strikethrough
red text. A separate Final version with all changes accepted is available in this
publication.
---------------------- Page: 6 ----------------------
– 4 – IEC 61557-7:2019+AMD1:2023 CSV
© IEC 2023
International Standard IEC 61557-7 has been prepared by IEC technical committee 85:
Measuring equipment for electrical and electromagnetic quantities.
This third edition constitutes a technical revision.
This edition includes the following changes with respect to the previous edition:
a) alignment of the structure with that of the whole IEC 61557 series;
b) updated requirements in 4.3 in accordance with new editions of IEC 61010-1
and IEC 61010-031;
c) the information on markings was extended;
d) the information on the operating instructions was extended;
e) complement to the information on the testing of leads;
f) test leads for insulated conductors were introduced;
g) Annex B was added with information on phase sequence tests and indications.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
This International Standard is to be used in conjunction with IEC 61557-1:2019.
A list of all parts of the IEC 61557 series, published under the general title Electrical safety in
low voltage distribution systems up to 1 000 V AC and 1 500 V DC – Equipment for testing,
measuring or monitoring of protective measures, can be found on the IEC website
The committee has decided that the contents of this document and its amendment will remain
unchanged until the stability date indicated on the IEC website under webstore.iec.ch in the
data related to the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
---------------------- Page: 7 ----------------------
IEC 61557-7:2019+AMD1:2023 CSV – 5 –
© IEC 2023
ELECTRICAL SAFETY IN LOW VOLTAGE DISTRIBUTION SYSTEMS
UP TO 1 000 V AC AND 1 500 V DC –
EQUIPMENT FOR TESTING, MEASURING OR MONITORING
OF PROTECTIVE MEASURES –
Part 7: Phase sequence
1 Scope
This part of IEC 61557 specifies the requirements applicable to measuring equipment for
testing the phase sequence in three-phase distribution systems. Indication of the phase
sequence can be mechanical, visual and/or audible.
This document does not apply to additional measurements for other quantities. It does not
apply to monitoring relays.
NOTE Common worldwide three-phase distribution systems are depicted in IEC 61010-1:2010, Annex I and
IEC 61010-1:2010/AMD1:2016, Annex I.
2 Normative references
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.
IEC 61010-1:2010, Safety requirements for electrical equipment for measurement, control,
and laboratory use – Part 1: General requirements
1
IEC 61010-1:2010/AMD1:2016
IEC 61010-2-030:2017, Safety requirements for electrical equipment for measurement, control,
and laboratory use – Part 2-030: Particular requirements for equipment having testing or
measuring circuits
IEC 61010-031, Safety requirements for electrical equipment for measurement, control and
laboratory use – Part 031: Safety requirements for hand-held and hand-manipulated
assemblies for electrical test and measurement
IEC 61557-1:2019 Electrical safety in low voltage distribution systems up to 1 000 V AC and
1 500 V DC – Equipment for testing, measuring or monitoring of protective measures – Part 1:
General requirements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61557-1 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
——————
1
A consolidated version of this publication exists, comprising IEC 61010-1:2010 and
IEC 61010-1:2010/AMD1:2016.
---------------------- Page: 8 ----------------------
– 6 – IEC 61557-7:2019+AMD1:2023 CSV
© IEC 2023
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
phase sequence indicator
instrument intended to indicate, in a polyphase system, the sequence in which the
instantaneous voltages of the phase conductors reach their maximum values
[SOURCE: IEC 60050-313:2001, 313-01-21]
3.2
phase sequence indication
information displayed by a phase sequence indicator
3.3
phase sequence test
test taken to determine that the phase sequence of a polyphase winding is correct
[SOURCE: IEC 60050-411:1996, 411-53-45]
4 Requirements
4.1 General
In addition to the requirements of IEC 61557-1:2019, Clause 4, the requirements of Clause 4
of this document shall apply.
4.2 Indication
All indications shall be unambiguously displayed on the phase sequence indicator when the
input to the phase indicator is between 85 % and 110 % of the nominal system voltage and
between 95 % and 105 % of the nominal system frequency.
Indications shall also be unambiguously detectable in the presence of visual or audible
interference.
The phase sequence indicator shall display a valid phase sequence indication, positive or
negative, if the values of the voltage to earth of the three phases are within the voltage range
specified above and the phase delay between two consecutive phases is 120°.
The phase sequence indicator shall not display a valid phase sequence indication, positive or
negative, if the three-phase distribution system is heavily unbalanced.
NOTE An unbalanced system could be due to unbalanced loads on the three phases or due to cabling errors.
In particular the measuring equipment shall not display a valid phase sequence indication in
the following cases:
1) one or more of the phase conductors are open-circuit;
2) one or more of the phase conductors are connected to neutral or protective earth;
3) two conductors are connected to the same phase.
The specific indications displayed in the above error cases shall be mentioned in the
operating instructions of the phase sequence indicator.
The limits of unbalance in amplitude and in phase delay that the phase sequence indicator
can handle reliably shall also be mentioned in the operating instructions.
---------------------- Page: 9 ----------------------
IEC 61557-7:2019+AMD1:2023 CSV – 7 –
© IEC 2023
4.3 Measuring equipment
4.3.1 General
The measuring equipment for the phase sequence test is intended for temporary operation,
but shall withstand continuous operation.
Equipment intended to be used on the distribution system shall be rated at least for
measurement category III according to IEC 61010-2-030.
Equipment intended to be used on socket outlets only can be rated for measurement category
II according to IEC 61010-2-030.
The measuring equipment shall not be damaged nor shall the user be exposed to danger
when the measuring equipment is connected to 120 % of the rated system voltage or to 120 %
of the maximum voltage of its rated voltage range.
The phase sequence test (see Annex B) can be realised with test probes for direct contact
with live parts, conductors or terminals, or with capacitive test clamps clips for inductive non-
contact phase detection on insulated or uninsulated conductors.
4.3.2 Portable phase sequence indicator
Portable phase sequence indicators shall be housed in an enclosure of insulating material and
comply with the requirements for double insulation or reinforced insulation (protection class II).
Portable phase sequence indicators shall be designed in such a manner that when either one
or two measuring leads are connected to earth and the remaining measuring leads are
connected to their corresponding phase conductors, the resulting total current to earth should
not exceed 3,5 mA RMS. The phase conductors shall be at 110 % of the maximum rated
voltage for which the equipment is designed.
4.3.3 Test leads for direct contact with live parts and accessories
Phase sequence indicators designed for direct contact to live parts shall be provided with
permanently connected test leads or with terminals for removable test leads complying with
IEC 61010-031.
The following applies to leads.
Test probes, test leads, clips and other accessories used with phase sequence indicators
shall be in accordance with the requirements of IEC 61010-031.
A test lead cable that has a wear indicator shall, at the minimum, provide double insulation or
reinforced insulation when new and, at the minimum, basic insulation when the wear indicator
is reached (see IEC 61010-031).
Portable measuring equipment, together with its test leads, shall comply with the
requirements for mechanical strength according to in accordance with IEC 61010-1 and in
addition shall be tested in accordance with 6.4 6.3.1.
These requirements do not apply when the phase sequence indicator forms part of a
multi-purpose instrument with provisions for carrying.
---------------------- Page: 10 ----------------------
– 8 – IEC 61557-7:2019+AMD1:2023 CSV
© IEC 2023
4.3.4 Test clips for non-contact phase detection
Phase sequence indicators designed for operation without direct contact to live parts shall be
provided with leads and capacitive test clips for phase detection on insulated or uninsulated
conductors complying with the requirements for spring-loaded clips of IEC 61010-031.
5 Marking and operating instructions
5.1 Marking
In addition to IEC 61557-1:2019, 5.1 and 5.2, the following information shall be provided on
the measuring equipment:
– symbol for double insulation in accordance with IEC 61010-1:2010, Table 1, symbol 11;
– designation of leads L1, L2 and L3 on the equipment and on the leads;
– the measurement category shall be printed on the equipment close to the test lead
connection.
5.2 Operating instructions
IEC 61557-1:2019, 5.3 applies.
In addition to IEC 61557-1:2019, 5.3, the following information shall be provided in the
operating instructions:
– specific indications for the error cases of 4.2,
– limits of unbalance in amplitude and phase delay handled reliably by the phase sequence
indicator.
6 Tests
6.1 General
6.1.1 Tests – General
In addition to the tests of IEC 61557-1:2019, Clause 6, the following tests shall be performed.
6.1.2 Visual display
Tests of the visual display are performed under the following conditions.
The display shall be unambiguously discernible by a person an observer with 6/6 vision
average sight from a distance of 500 mm 0,5 m at ambient lighting levels from 30 lx to
1 000 lx. During the measurement, the measuring equipment shall be placed on a matt grey
surface (type test).
A visual comparison under reference conditions with equipment that has successfully passed
the type test is adequate for a routine test with respect to the visual display. The display on
the item under test shall produce a similar or better readability (routine tests).
6.1.3 Audible indication (if applicable)
The test for the audible indication is performed at a sound level of L = 75 dB (white noise).
AF
The indication shall generate a sound between 1 kHz and 4 kHz and be unambiguously
discernible by a person with a hearing loss of less than 15 dB HL under these conditions
(routine test).
---------------------- Page: 11 ----------------------
IEC 61557-7:2019+AMD1:2023 CSV – 9 –
© IEC 2023
The audible indication shall generate a sound level equal to or greater than 58,5 dB if
continuous or 55,5 dB if intermittent in the frequency range between 1 kHz and 4 kHz.
The test shall be performed in accordance with Figure 1.
The alternative test consisting in comparing the perceptibility of the audible indication under
reference conditions with a phase sequence indicator that has successfully passed the type
test is adequate for the routine test. The sound on the item under test shall produce a similar
or better indication (routine test).
Dimensions in millimetres
Key
A hemisphere measurement distance
B microphone
C sound emitter
D phase sequence indicator
E sound absorbing material
F mounting surface
Figure 1 – Test set-up for measurement of perceptibility of the audible indication
6.2 Leakage current
The requirements under 4.3.2 shall be tested as follows.
The phase sequence indicator shall be connected in series with a current measuring
instrument that has one lead connected with earth, and with the other interconnected leads
connected with a phase conductor at a voltage of 110 % of its rated voltage or a voltage at
the upper limit of its rated voltage range. The magnitude of the current shall not exceed the
value specified under 4.3.2.
This test shall be executed on each conductor (routine test).
6.3 Test of mechanical requirements (type tests)
6.3.1 Mechanical shock test
For the purpose of a mechanical shock test, the item under test shall be suspended as shown
in Annex A, Figure A.1, using a pendulum length of 2 m. The item under test shall be dropped
---------------------- Page: 12 ----------------------
– 10 – IEC 61557-7:2019+AMD1:2023 CSV
© IEC 2023
in a pendulum movement with a deflection of 1 m in height to hit a hard wooden plate 50 mm
thick. The test shall be carried out so that each of the sides of the enclosure parallel to the
suspension hits the wood once.
6.3.2 Test of leads for direct contact with live parts
The strain relief of permanently attached leads shall be tested by a drop test in accordance
with Annex A, Figure A.2, in the following manner:
– the item under test shall be suspended so that it is caught with the extended lead after a
free drop of 2 m;
– the item under test shall be dropped three times from the suspension point for each of the
leads;
...
IEC 61557-7
®
Edition 3.0 2019-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electrical safety in low voltage distribution systems up to 1 000 V a.c. and
1 500 V d.c. – Equipment for testing, measuring or monitoring of protective
measures –
Part 7: Phase sequence
Sécurité électrique dans les réseaux de distribution basse tension au plus
égale à 1 000 V c.a. et 1 500 V c.c. – Dispositifs de contrôle, de mesure ou
de surveillance de mesures de protection –
Partie 7: Ordre de phases
IEC 61557-7:2019-07(en-fr)
---------------------- Page: 1 ----------------------
THIS PUBLICATION IS COPYRIGHT PROTECTED
Copyright © 2019 IEC, Geneva, Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.
Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie
et les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.
IEC Central Office Tel.: +41 22 919 02 11
3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.
About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.
IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
The advanced search enables to find IEC publications by a The world's leading online dictionary on electrotechnology,
variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary
(IEV) online.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Glossary - std.iec.ch/glossary
details all new publications released. Available online and 67 000 electrotechnical terminology entries in English and
once a month by email. French extracted from the Terms and Definitions clause of
IEC publications issued since 2002. Some entries have been
IEC Customer Service Centre - webstore.iec.ch/csc collected from earlier publications of IEC TC 37, 77, 86 and
If you wish to give us your feedback on this publication or CISPR.
need further assistance, please contact the Customer Service
Centre: sales@iec.ch.
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.
A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.
Recherche de publications IEC - Electropedia - www.electropedia.org
webstore.iec.ch/advsearchform Le premier dictionnaire d'électrotechnologie en ligne au
La recherche avancée permet de trouver des publications IEC monde, avec plus de 22 000 articles terminologiques en
en utilisant différents critères (numéro de référence, texte, anglais et en français, ainsi que les termes équivalents dans
comité d’études,…). Elle donne aussi des informations sur les 16 langues additionnelles. Egalement appelé Vocabulaire
projets et les publications remplacées ou retirées. Electrotechnique International (IEV) en ligne.
IEC Just Published - webstore.iec.ch/justpublished Glossaire IEC - std.iec.ch/glossary
Restez informé sur les nouvelles publications IEC. Just 67 000 entrées terminologiques électrotechniques, en anglais
Published détaille les nouvelles publications parues. et en français, extraites des articles Termes et Définitions des
Disponible en ligne et une fois par mois par email. publications IEC parues depuis 2002. Plus certaines entrées
antérieures extraites des publications des CE 37, 77, 86 et
Service Clients - webstore.iec.ch/csc CISPR de l'IEC.
Si vous désirez nous donner des commentaires sur cette
publication ou si vous avez des questions contactez-nous:
sales@iec.ch.
---------------------- Page: 2 ----------------------
IEC 61557-7
®
Edition 3.0 2019-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electrical safety in low voltage distribution systems up to 1 000 V a.c. and
1 500 V d.c. – Equipment for testing, measuring or monitoring of protective
measures –
Part 7: Phase sequence
Sécurité électrique dans les réseaux de distribution basse tension au plus
égale à 1 000 V c.a. et 1 500 V c.c. – Dispositifs de contrôle, de mesure ou
de surveillance de mesures de protection –
Partie 7: Ordre de phases
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.220.20; 29.080.01; 29.240.01 ISBN 978-2-8322-7161-2
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: 3 ----------------------
– 2 – IEC 61557-7:2019 © IEC 2019
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Requirements . 6
4.1 General . 6
4.2 Indication . 6
4.3 Measuring equipment . 7
4.3.1 General . 7
4.3.2 Portable phase sequence indicator . 7
4.3.3 Test leads for direct contact with live parts and accessories . 7
5 Marking and operating instructions . 8
5.1 Marking . 8
5.2 Operating instructions . 8
6 Tests . 8
6.1 General . 8
6.1.1 Tests – General . 8
6.1.2 Visual display . 8
6.1.3 Audible indication (if applicable) . 8
6.2 Leakage current . 8
6.3 Test of mechanical requirements (type tests) . 9
6.3.1 Mechanical shock test . 9
6.3.2 Test of leads for direct contact with live parts . 9
6.4 Overvoltage . 9
6.5 Test of markings . 9
Annex A (normative) Illustrations for mechanical tests . 10
Annex B (informative) Phase sequence test . 12
B.1 Phase sequence test – Tripolar connection . 12
B.2 Phase sequence test – Sequential bipolar connection . 12
Bibliography . 14
Figure A.1 – Mechanical shock test . 10
Figure A.2 – Drop test . 11
Figure B.1 – Tripolar connection . 12
Figure B.2 – Sequential bipolar connection . 13
---------------------- Page: 4 ----------------------
IEC 61557-7:2019 © IEC 2019 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL SAFETY IN LOW VOLTAGE DISTRIBUTION SYSTEMS
UP TO 1 000 V AC AND 1 500 V DC –
EQUIPMENT FOR TESTING, MEASURING OR MONITORING
OF PROTECTIVE MEASURES –
Part 7: Phase sequence
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 61557-7 has been prepared by IEC technical committee 85:
Measuring equipment for electrical and electromagnetic quantities.
This third edition cancels and replaces the second edition published in 2007. This edition
constitutes a technical revision.
This edition includes the following changes with respect to the previous edition:
a) alignment of the structure with that of the whole IEC 61557 series;
b) updated requirements in 4.3 in accordance with new editions of IEC 61010-1
and IEC 61010-031;
c) the information on markings was extended;
d) the information on the operating instructions was extended;
---------------------- Page: 5 ----------------------
– 4 – IEC 61557-7:2019 © IEC 2019
e) complement to the information on the testing of leads;
f) test leads for insulated conductors were introduced;
g) Annex B was added with information on phase sequence tests and indications.
The text of this International Standard is based on the following documents:
FDIS Report on voting
85/683/FDIS 85/698/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
This International Standard is to be used in conjunction with IEC 61557-1:2019.
A list of all parts of the IEC 61557 series, published under the general title Electrical safety in
low voltage distribution systems up to 1 000 V AC and 1 500 V DC – Equipment for testing,
measuring or monitoring of protective measures, can be found on the IEC website
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates that it
contains colours which are considered to be useful for the correct understanding of its
contents. Users should therefore print this document using a colour printer.
---------------------- Page: 6 ----------------------
IEC 61557-7:2019 © IEC 2019 – 5 –
ELECTRICAL SAFETY IN LOW VOLTAGE DISTRIBUTION SYSTEMS
UP TO 1 000 V AC AND 1 500 V DC –
EQUIPMENT FOR TESTING, MEASURING OR MONITORING
OF PROTECTIVE MEASURES –
Part 7: Phase sequence
1 Scope
This part of IEC 61557 specifies the requirements applicable to measuring equipment for
testing the phase sequence in three-phase distribution systems. Indication of the phase
sequence can be mechanical, visual and/or audible.
This document does not apply to additional measurements for other quantities. It does not
apply to monitoring relays.
NOTE Common worldwide three-phase distribution systems are depicted in IEC 61010-1.
2 Normative references
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.
IEC 61010-1:2010, Safety requirements for electrical equipment for measurement, control,
and laboratory use – Part 1: General requirements
1
IEC 61010-1:2010/AMD1:2016
IEC 61010-2-030:2017, Safety requirements for electrical equipment for measurement, control,
and laboratory use – Part 2-030: Particular requirements for equipment having testing or
measuring circuits
IEC 61010-031, Safety requirements for electrical equipment for measurement, control and
laboratory use – Part 031: Safety requirements for hand-held and hand-manipulated
assemblies for electrical test and measurement
IEC 61557-1:2019 Electrical safety in low voltage distribution systems up to 1 000 V AC and
1 500 V DC – Equipment for testing, measuring or monitoring of protective measures – Part 1:
General requirements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61557-1 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
——————
1
A consolidated version of this publication exists, comprising IEC 61010-1:2010 and
IEC 61010-1:2010/AMD1:2016.
---------------------- Page: 7 ----------------------
– 6 – IEC 61557-7:2019 © IEC 2019
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
phase sequence indicator
instrument intended to indicate, in a polyphase system, the sequence in which the
instantaneous voltages of the phase conductors reach their maximum values
[SOURCE: IEC 60050-313:2001, 313-01-21]
3.2
phase sequence indication
information displayed by a phase sequence indicator
3.3
phase sequence test
test taken to determine that the phase sequence of a polyphase winding is correct
[SOURCE: IEC 60050-411:1996, 411-53-45]
4 Requirements
4.1 General
In addition to the requirements of IEC 61557-1:2019, Clause 4, the requirements of Clause 4
of this document shall apply.
4.2 Indication
All indications shall be unambiguously displayed on the phase sequence indicator when the
input to the phase indicator is between 85 % and 110 % of the nominal system voltage and
between 95 % and 105 % of the nominal system frequency.
Indications shall also be unambiguously detectable in the presence of visual or audible
interference.
The phase sequence indicator shall display a valid phase sequence indication, positive or
negative, if the values of the voltage to earth of the three phases are within the voltage range
specified above and the phase delay between two consecutive phases is 120°.
The phase sequence indicator shall not display a valid phase sequence indication, positive or
negative, if the three-phase distribution system is heavily unbalanced.
NOTE An unbalanced system could be due to unbalanced loads on the three phases or due to cabling errors.
In particular the measuring equipment shall not display a valid phase sequence indication in
the following cases:
1) one or more of the phase conductors are open-circuit;
2) one or more of the phase conductors are connected to neutral or protective earth;
3) two conductors are connected to the same phase.
The specific indications displayed in the above error cases shall be mentioned in the
operating instructions of the phase sequence indicator.
The limits of unbalance in amplitude and in phase delay that the phase sequence indicator
can handle reliably shall also be mentioned in the operating instructions.
---------------------- Page: 8 ----------------------
IEC 61557-7:2019 © IEC 2019 – 7 –
4.3 Measuring equipment
4.3.1 General
The measuring equipment for the phase sequence test is intended for temporary operation,
but shall withstand continuous operation.
Equipment intended to be used on the distribution system shall be rated at least for
measurement category III according to IEC 61010-2-030.
Equipment intended to be used on socket outlets only can be rated for measurement category
II according to IEC 61010-2-030.
The measuring equipment shall not be damaged nor shall the user be exposed to danger
when the measuring equipment is connected to 120 % of the rated system voltage or to 120 %
of the maximum voltage of its rated voltage range.
The phase sequence test (see Annex B) can be realised with test probes for direct contact
with live parts, conductors or terminals, or with test clamps for inductive detection on
insulated conductors.
4.3.2 Portable phase sequence indicator
Portable phase sequence indicators shall be housed in an enclosure of insulating material and
comply with the requirements for double insulation or reinforced insulation (protection class II).
Portable phase sequence indicators shall be designed in such a manner that when either one
or two measuring leads are connected to earth and the remaining measuring leads are
connected to their corresponding phase conductors, the resulting total current to earth should
not exceed 3,5 mA RMS. The phase conductors shall be at 110 % of the maximum rated
voltage for which the equipment is designed.
4.3.3 Test leads for direct contact with live parts and accessories
Phase sequence indicators designed for direct contact to live parts shall be provided with
permanently connected test leads or with terminals for removable test leads complying with
IEC 61010-031.
The following applies to leads.
Test probes, test leads, clips and other accessories used with phase sequence indicators
shall be in accordance with the requirements of IEC 61010-031.
A test lead cable that has a wear indicator shall, at the minimum, provide double insulation or
reinforced insulation when new and, at the minimum, basic insulation when the wear indicator
is reached (see IEC 61010-031).
Portable measuring equipment, together with its test leads, shall comply with the
requirements for mechanical strength according to IEC 61010-1 and in addition shall be tested
in accordance with 6.4.
These requirements do not apply when the phase sequence indicator forms part of a
multi-purpose instrument with provisions for carrying.
---------------------- Page: 9 ----------------------
– 8 – IEC 61557-7:2019 © IEC 2019
5 Marking and operating instructions
5.1 Marking
In addition to IEC 61557-1:2019, 5.1 and 5.2, the following information shall be provided on
the measuring equipment:
– symbol for double insulation in accordance with IEC 61010-1:2010, Table 1, symbol 11;
– designation of leads L1, L2 and L3 on the equipment and on the leads;
– the measurement category shall be printed on the equipment close to the test lead
connection.
5.2 Operating instructions
IEC 61557-1:2019, 5.3 applies.
6 Tests
6.1 General
6.1.1 Tests – General
In addition to the tests of IEC 61557-1:2019, Clause 6, the following tests shall be performed.
6.1.2 Visual display
Tests of the visual display are performed under the following conditions.
The display shall be unambiguously discernible by a person with 6/6 vision from a distance of
500 mm at ambient lighting levels from 30 lx to 1 000 lx. During the measurement, the
measuring equipment shall be placed on a matt grey surface (type test).
A visual comparison under reference conditions with equipment that has successfully passed
the type test is adequate for a routine test with respect to the visual display. The display on
the item under test shall produce a similar or better readability (routine tests).
6.1.3 Audible indication (if applicable)
The test for the audible indication is performed at a sound level of L = 75 dB (white noise).
AF
The indication shall generate a sound between 1 kHz and 4 kHz and be unambiguously
discernible by a person with a hearing loss of less than 15 dB HL under these conditions
(routine test).
6.2 Leakage current
The requirements under 4.3.2 shall be tested as follows.
The phase sequence indicator shall be connected in series with a current measuring
instrument that has one lead connected with earth, and with the other interconnected leads
connected with a phase conductor at a voltage of 110 % of its rated voltage or a voltage at
the upper limit of its rated voltage range. The magnitude of the current shall not exceed the
value specified under 4.3.2.
This test shall be executed on each conductor (routine test).
---------------------- Page: 10 ----------------------
IEC 61557-7:2019 © IEC 2019 – 9 –
6.3 Test of mechanical requirements (type tests)
6.3.1 Mechanical shock test
For the purpose of a mechanical shock test, the item under test shall be suspended as shown
in Annex A, Figure A.1, using a pendulum length of 2 m. The item under test shall be dropped
in a pendulum movement with a deflection of 1 m in height to hit a hard wooden plate 50 mm
thick. The test shall be carried out so that each of the sides of the enclosure parallel to the
suspension hits the wood once.
6.3.2 Test of leads for direct contact with live parts
The strain relief of permanently attached leads shall be tested by a drop test in accordance
with Annex A, Figure A.2, in the following manner:
– the item under test shall be suspended so that it is caught with the extended lead after a
free drop of 2 m;
– the item under test shall be dropped three times from the suspension point for each of the
leads;
– the enclosure of the measuring equipment shall be free from damage;
– permanently attached leads shall not have become detached from the measuring
equipment;
– live parts of the leads connected by means of plugs shall remain inaccessible when they
have become unplugged from the measuring equipment;
– no parts inside the measuring equipment shall have become loose.
6.4 Overvoltage
The applicable requirement of 4.3.1 shall be tested as follows:
Compliance with the requirements given in 4.3.1 shall be tested by connecting, for a duration
of at least 10 min, the item under test to a three-phase system at 120 % of the rated system
voltage or, in the case of multi-range measuring equipment, at 120 % of all rated voltages
(type test).
The surface temperature of EUT shall be measured and checked according to IEC 61010-1.
Compliance with the requirements given in 4.3 shall be tested by operating the item under test
for a duration of at least 1 h at the rated voltage or, in the case of multi-range measuring
equipment, at all rated voltage values (type test).
6.5 Test of markings
The markings shall be checked in respect of legibility by a visual inspection (type test).
---------------------- Page: 11 ----------------------
– 10 – IEC 61557-7:2019 © IEC 2019
Annex A
(normative)
Illustrations for mechanical tests
Mechanical shock tests shall be performed according to Figure A.1.
Dimensions in metres
Figure A.1 – Mechanical shock test
---------------------- Page: 12 ----------------------
IEC 61557-7:2019 © IEC 2019 – 11 –
Drop tests shall be performed according to Figure A.2.
Dimensions in metres
Key
a original lead A initial position where the equipment is held
b joint B end position after the release of the equipment
c extension to 2 m
Figure A.2 – Drop test
---------------------- Page: 13 ----------------------
– 12 – IEC 61557-7:2019 © IEC 2019
Annex B
(informative)
Phase sequence test
B.1 Phase sequence test – Tripolar connection
The measuring equipment for the phase sequence test with tripolar connection is connected
to the three-phase distribution system using three separate test probes marked L1, L2 and L3
(see 5.1).
Each test probe is connected to the conductor or terminal foreseen to be at the corresponding
phase L1, L2 or L3 of the distribution system.
Figure B.1 – Tripolar connection
The phase sequence indication is positive, commonly called "clockwise" (CW) or "right" (R), if
the three phases are in the foreseen phase sequence.
The phase sequence indication is negative, commonly called "counter-clockwise" (CCW) or
"left" (L), if the three phases are in a sequence different than foreseen: two of the three phase
connections are crossed.
NOTE New phase sequence tests carried out after crossing tests probes L
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.