SIST EN IEC 60404-3:2023
(Main)Magnetic materials - Part 3: Methods of measurement of the magnetic properties of electrical steel strip and sheet by means of a single sheet tester (IEC 60404-3:2022)
Magnetic materials - Part 3: Methods of measurement of the magnetic properties of electrical steel strip and sheet by means of a single sheet tester (IEC 60404-3:2022)
IEC 60404-3:2022 is available as IEC 60404-3:2022 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 60404-3:2022 is applicable to grain-oriented and non-oriented electrical steel strip and sheet for measurement of AC magnetic properties at power frequencies. The object of this document is to define the general principles and the technical details of the measurement of the magnetic properties of electrical steel strip and sheet by means of a single sheet tester (SST). This edition includes the following significant technical changes with respect to the previous edition:
- Annex A was revised. The method of determining the yokes’ lamination resistance was added to Annex A;
- Annex B of the consolidated version of 2010 referred to calibration of the SST using the Epstein method. It was cancelled;
- Annex B (new), Annex C and Annex D were revised, they are for information only;
- Annex C was modified taking account of the new situation regarding P and R grades;
- Annex D was amended by addition of Clause D.4 on the numerical air flux compensation.
Magnetische Werkstoffe - Teil 3: Verfahren zur Bestimmung der magnetischen Eigenschaften von Elektroband und -blech mit Hilfe eines Tafelmessgerätes (IEC 60404-3:2022)
Matériaux magnétiques - Partie 3: Méthodes de mesure des caractéristiques magnétiques des bandes et tôles magnétiques en acier à l'aide de l'essai sur tôle unique (IEC 60404-3:2022)
IEC 60404-3:2022 est disponible sous forme de IEC 60404-3:2022 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.
L'IEC 60404-3:2022 s'applique aux bandes et tôles magnétiques en acier à grains orientés et à grains non orientés pour le mesurage des caractéristiques magnétiques en courant alternatif aux fréquences industrielles. Le présent document a pour objet de définir les principes généraux et les détails techniques pour le mesurage des caractéristiques magnétiques des bandes et tôles magnétiques en acier à l'aide de l'essai sur tôle unique (SST, Single Sheet Tester). Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- l'Annexe A a été révisée. La méthode de détermination de la résistance des bandes des culasses a été ajoutée à l'Annexe A;
- l'Annexe B de l'édition consolidée de 2010 faisait référence à l'étalonnage du SST à l'aide de la méthode Epstein. Elle a été annulée;
- l'Annexe B (nouvelle), l'Annexe C et l'Annexe D ont été révisées et sont seulement informatives;
- l'Annexe C a été modifiée compte tenu de la nouvelle situation concernant les qualités P et R;
- l'Annexe D a été amendée par ajout de l'Article D.4 relatif à la compensation numérique du flux d'air.
Magnetni materiali - 3. del: Metode merjenja magnetnih lastnosti električnih jeklenih trakov in pločevine z uporabo enolistnega preskuševalnika (IEC 60404-3:2022)
Standard IEC 60404-3:2022 je na voljo kot IEC 60404-3:2022 RLV, ki vsebuje mednarodni standard in njegovo različico z revizijami, ki prikazujejo vse spremembe tehnične vsebine v primerjavi s prejšnjo izdajo. Standard IEC 60404-3:2022 se uporablja za zrnato orientirano in neorientirano elektropločevino ter trakove za merjenje magnetnih lastnosti pri izmeničnem toku in omrežnih frekvencah. Namen tega dokumenta je opredeliti splošna načela in tehnične podrobnosti za merjenje magnetnih lastnosti električnih jeklenih trakov in pločevine z uporabo enolistnega preskuševalnika (SST). Ta izdaja v primerjavi s prejšnjo vključuje naslednje pomembne tehnične spremembe:
– Dodatek A je bil prenovljen. Dodana je bila metoda za določitev odpornosti tuljav pri laminiranju.
– Dodatek B prečiščene različice iz leta 2010, ki se navezuje na kalibriranje enolistnega preskuševalnika z Epsteinovo metodo, je bil razveljavljen.
– Dodatek B (nov), dodatek C in dodatek D so bili revidirani; namenjeni so zgolj za informativne namene.
– Dodatek C je bil spremenjen ob upoštevanju nove situacije v zvezi z razredoma P in R.
– Dodatek D je bil dopolnjen s točko D.4 o numerični kompenzaciji pretoka zraka.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN IEC 60404-3:2023
01-februar-2023
Magnetni materiali - 3. del: Metode merjenja magnetnih lastnosti električnih
jeklenih trakov in pločevine z uporabo enolistnega preskuševalnika (IEC 60404-
3:2022)
Magnetic materials - Part 3: Methods of measurement of the magnetic properties of
electrical steel strip and sheet by means of a single sheet tester (IEC 60404-3:2022)
Magnetische Werkstoffe - Teil 3: Verfahren zur Bestimmung der magnetischenEigenschaften von Elektroband und -blech mit Hilfe eines Tafelmessgerätes (IEC 60404-
3:2022)Matériaux magnétiques - Partie 3: Méthodes de mesure des caractéristiques
magnétiques des bandes et tôles magnétiques en acier à l'aide de l'essai sur tôle unique
(IEC 60404-3:2022)Ta slovenski standard je istoveten z: EN IEC 60404-3:2022
ICS:
17.220.20 Merjenje električnih in Measurement of electrical
magnetnih veličin and magnetic quantities
29.030 Magnetni materiali Magnetic materials
SIST EN IEC 60404-3:2023 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN IEC 60404-3:2023
EUROPEAN STANDARD EN IEC 60404-3
NORME EUROPÉENNE
EUROPÄISCHE NORM December 2022
ICS 29.030; 17.220.20
English Version
Magnetic materials - Part 3: Methods of measurement of the
magnetic properties of electrical steel strip and sheet by means
of a single sheet tester
(IEC 60404-3:2022)
Matériaux magnétiques - Partie 3: Méthodes de mesure des Magnetische Werkstoffe - Teil 3: Verfahren zur Bestimmung
caractéristiques magnétiques des bandes et tôles der magnetischen Eigenschaften von Elektroband und -
magnétiques en acier à l'aide de l'essai sur tôle unique blech mit Hilfe eines Tafelmessgerätes
(IEC 60404-3:2022) (IEC 60404-3:2022)This European Standard was approved by CENELEC on 2022-12-13. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60404-3:2022 E---------------------- Page: 3 ----------------------
SIST EN IEC 60404-3:2023
EN IEC 60404-3:2022 (E)
European foreword
The text of document 68/699/CDV, future edition 3 of IEC 60404-3, prepared by IEC/TC 68 "Magnetic
alloys and steels" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
EN IEC 60404-3:2022.The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2023-09-13
level by publication of an identical national standard or by endorsement• latest date by which the national standards conflicting with the (dow) 2025-12-13
document have to be withdrawnAttention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.Endorsement notice
The text of the International Standard IEC 60404-3:2022 was approved by CENELEC as a European
Standard without any modification.In the official version, for Bibliography, the following note has to be added for the standard indicated:
IEC 60404-8-7:2020 NOTE Harmonized as EN 10107:2022 (modified)---------------------- Page: 4 ----------------------
SIST EN IEC 60404-3:2023
EN IEC 60404-3:2022 (E)
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cenelec.eu.Publication Year Title EN/HD Year
IEC 60050-121 - International Electrotechnical Vocabulary - - -
Part 121: Electromagnetism
IEC 60050-221 - International Electrotechnical Vocabulary. - -
Chapter 221: Magnetic materials and
components
IEC 60404-13 - Magnetic materials - Part 13: Methods of EN IEC 60404-13 -
measurement of resistivity, density and
stacking factor of electrical steel strip and
sheet
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SIST EN IEC 60404-3:2023
IEC 60404-3
Edition 3.0 2022-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Magnetic materials –
Part 3: Methods of measurement of the magnetic properties of electrical steel
strip and sheet by means of a single sheet tester
Matériaux magnétiques –
Partie 3: Méthodes de mesure des caractéristiques magnétiques des bandes et
tôles magnétiques en acier à l'aide de l'essai sur tôle unique
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.220.20; 29.030 ISBN 978-2-8322-5961-0
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 CommissionMarque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 7 ----------------------
SIST EN IEC 60404-3:2023
– 2 – IEC 60404-3:2022 © IEC 2022
CONTENTS
FOREWORD ........................................................................................................................... 4
1 Scope .............................................................................................................................. 6
2 Normative references ...................................................................................................... 6
3 Terms and definitions ...................................................................................................... 6
4 General principles of AC measurements .......................................................................... 7
4.1 General ................................................................................................................... 7
4.2 Principle of the single sheet tester method .............................................................. 7
4.3 Test apparatus ........................................................................................................ 7
4.3.1 Yokes .............................................................................................................. 7
4.3.2 Windings ......................................................................................................... 9
4.4 Air flux compensation ............................................................................................ 10
4.5 Test specimen ...................................................................................................... 10
4.6 Power supply ........................................................................................................ 11
5 Determination of the specific total loss .......................................................................... 11
5.1 Principle of measurement...................................................................................... 11
5.2 Apparatus ............................................................................................................. 11
5.2.1 Voltage measurement .................................................................................... 11
5.2.2 Frequency measurement ............................................................................... 12
5.2.3 Power measurement ...................................................................................... 12
5.3 Measurement procedure of the specific total loss .................................................. 12
5.3.1 Preparation of measurement .......................................................................... 12
5.3.2 Adjustment of power supply ........................................................................... 12
5.3.3 Measurements ............................................................................................... 13
5.3.4 Reproducibility of the measurement of the specific total loss ......................... 14
6 Determination of magnetic field strength, primary current and specific apparent
power ............................................................................................................................ 14
6.1 General ................................................................................................................. 14
6.2 Principle of measurement...................................................................................... 14
6.2.1 Peak value of the magnetic polarization ......................................................... 14
6.2.2 RMS value of the primary current................................................................... 14
6.2.3 Peak value of the magnetic field strength ...................................................... 15
6.3 Apparatus ............................................................................................................. 15
6.3.1 Average type voltmeter .................................................................................. 15
6.3.2 RMS current measurement ............................................................................ 16
6.3.3 Peak current measurement ............................................................................ 16
6.3.4 Power supply ................................................................................................. 16
6.3.5 Resistor R ..................................................................................................... 16
6.4 Measuring procedure ............................................................................................ 16
6.4.1 Preparation for measurement ........................................................................ 16
6.4.2 Measurement ................................................................................................. 16
6.4.3 Non-oriented material .................................................................................... 17
6.5 Determination of characteristics ............................................................................ 17
6.5.1 Determination of Ĵ ......................................................................................... 17
6.5.2 Determination of H ....................................................................................... 17
6.5.3 Determination of ....................................................................................... 18
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IEC 60404-3:2022 © IEC 2022 – 3 –
6.5.4 Determination of S ........................................................................................ 18
6.5.5 Reproducibility of the measurement of the specific apparent power ............... 19
7 Test report ..................................................................................................................... 19
Annex A (normative) Requirements concerning the manufacture of yokes ............................ 20
Annex B (informative) Check and verification of reliable performance of the SST set-
up by the use of reference samples and impact of the loss dissipated in the yokes ............... 22
Annex C (informative) Epstein to SST relationship for grain-oriented steel sheet ................. 25
Annex D (informative) Digital sampling methods for the determination of the magnetic
properties and numerical air flux compensation .................................................................... 28
D.1 General ................................................................................................................. 28
D.2 Technical details and requirements ....................................................................... 28
D.3 Calibration aspects ............................................................................................... 30
D.4 Numerical air flux compensation ........................................................................... 30
Bibliography .......................................................................................................................... 32
Figure 1 – Schematic diagrammes of the test apparatus ......................................................... 8
Figure 2 – Yoke dimensions .................................................................................................... 9
Figure 3 – Diagram of the connections of the five coils of the primary winding ........................ 9
Figure 4 – Circuit for the determination of the specific total loss............................................ 10
Figure 5 – Circuit for measuring the RMS value of the primary current .................................. 15
Figure 6 – Circuit for measuring the peak value of the magnetic field strength ...................... 15
Figure B.1 – Specific total loss vs. peak flux density (after J.Sievert [3] and1.85
G. Bertotti [4]); straight line: P ∝ B approximation (after C.Ragusa). ........................... 23
Figure C.1 – SST-Epstein relative difference δP for conventional grain-orientedmaterial versus magnetic polarization Ĵ ................................................................................. 27
Figure C.2 – SST-Epstein relative difference δHS for conventional grain-oriented
material versus magnetic polarization Ĵ ................................................................................. 27
Table B.1 – Loss dissipated by the yokes of a standard SST, determined from the loss
curves measured on 3 yoke pairs as shown in Figure B.1, and relevant quantitiesincluding the relative yokes' contribution, p ; exemplified using 5 standard grades ............... 24
Table C.1 – SST-Epstein relative differences δP and δHS and the conversion factor F
for conventional grain-oriented material in the polarization range 1,0 T to 1,8 T .................... 26
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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MAGNETIC MATERIALS –
Part 3: Methods of measurement of the magnetic properties of
electrical steel strip and sheet by means of a single sheet tester
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.
IEC 60404-3 has been prepared by IEC technical committee 68: Magnetic alloys and steels. It
is an International Standard.This third edition cancels and replaces the second edition published in 1992, Amendment
1:2002 and Amendment 2:2009. This edition constitutes a technical revision.This edition includes the following significant technical changes with respect to the previous
edition:a) Annex A was revised. The method of determining the yokes’ lamination resistance was
added to Annex A;b) Annex B of the consolidated version of 2010 referred to calibration of the SST using the
Epstein method. It was cancelled;c) Annex B (new), Annex C and Annex D were revised, they are for information only;
d) Annex C was modified taking account of the new situation regarding P and R grades;
e) Annex D was amended by addition of Clause D.4 on the numerical air flux compensation.
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IEC 60404-3:2022 © IEC 2022 – 5 –
The text of this International Standard is based on the following documents:
Draft Report on voting
68/699/CDV 68/710/RVC
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.A list of all parts in the IEC 60404 series, published under the general title Magnetic materials,
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 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 document 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: 11 ----------------------
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MAGNETIC MATERIALS –
Part 3: Methods of measurement of the magnetic properties of
electrical steel strip and sheet by means of a single sheet tester
1 Scope
This part of IEC 60404 is applicable to grain-oriented and non-oriented electrical steel strip and
sheet for measurement of AC magnetic properties at power frequencies.The object of this document is to define the general principles and the technical details of the
measurement of the magnetic properties of electrical steel strip and sheet by means of a single
sheet tester (SST).The single sheet tester is applicable to test specimens obtained from electrical steel strips and
sheets of any grade. The AC magnetic characteristics are determined for sinusoidal induced
voltages, for specified peak values of the magnetic polarization, for specific peak values of the
magnetic field strength and for a specified frequency.The measurements are made at an ambient temperature of (23±5)°C on test specimens which
have first been demagnetized.NOTE Throughout this document, the quantity "magnetic polarization" is used as defined in IEC 60050-221. In some
standards of the IEC 60404 series, the quantity "magnetic flux density" was used.
In order to support the long-term reliability of the performance of this set up and to understand
better the relationship between the Epstein method and the SST method, the informative
Annexes B and C, respectively, have been included.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 60050-121, International Electrotechnical Vocabulary – Part 121: Electromagnetism
IEC 60050-221, International Electrotechnical Vocabulary – Part 221: Magnetic materials and
componentsIEC 60404-13, Magnetic materials – Part 13: Methods of measurement of resistivity, density
and stacking factor of electrical steel strip and sheet3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-121 and
IEC 60050-221 apply.ISO and IEC maintain terminological databases for use in standardization at the following
addresses:• IEC Electropedia: available at https://www.electropedia.org/
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IEC 60404-3:2022 © IEC 2022 – 7 –
• ISO Online browsing platform: available at https://www.iso.org/obp
4 General principles of AC measurements
4.1 General
Clause 4 specifies the general conditions for the determination of AC magnetic properties of
electrical steel strip and sheet at power frequencies by means of a single sheet tester.
4.2 Principle of the single sheet tester methodThe test specimen comprises a sample of electrical steel sheet and is placed in the center of
two concentric windings:– an exterior primary winding (magnetizing winding);
– an interior secondary winding (voltage winding).
The flux closure is made by a magnetic circuit consisting of two identical yokes, the cross-
section of which is very large compared with that of the test specimen (see Figure 1).
The temperature changes of the specimen shall be kept below a level likely to produce stress
in the test specimen due to thermal expansion or contraction.4.3 Test apparatus
4.3.1 Yokes
Each yoke is in the form of a U made up of insulated sheets of grain-oriented electrical steel. It
shall have a low reluctance and a low specific total loss in the low magnetic polarization region
below 0,2 T (see Annex A). It shall be manufactured in accordance with the requirements of
Annex A.In order to reduce the effect of eddy currents and give a more homogeneous distribution of the
flux over the inside of the yokes, the yokes shall be made of a pair of wound cut C-cores or a
glued stack of laminations in which case the corners shall have staggered butt joints (see
Figure 1).The yoke shall have pole faces having a width of 25 mm ± 1 mm.
The two pole faces of each yoke shall be coplanar to within 0,5 mm and the gap between the
opposite pole faces of the yokes shall not exceed 0,005 mm at any point. Also, the yokes shall
be rigid in order to avoid creating mechanical stresses such as twisting, tensioning and
compression in the test specimen.The height of each yoke shall be between 90 mm and 150 mm. Each yoke shall have a width
of 500 mm and an inside length of 450 mm ± 1 mm (see Figure 2).There shall be a non-conducting, non-magnetic support on which the test specimen is placed,
between the vertical limbs of the bottom yokes. This support shall be centered and located in
the same plane as the bottom yoke pole faces so that the test specimen is in direct contact with
the pole faces without any gap. Care shall be taken that in no case the upper surface of the
support is positioned higher than the plane of the pole faces of the bottom yoke.
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a) Cross-section of the SST
b) Schematic view of the corner of a yoke with stacked lamination
Figure 1 – Schematic diagrammes of the test apparatus
The upper yoke shall be movable upwards to permit insertion of the test specimen. After
insertion of the test specimen, the upper yoke shall be lowered to close the magnetic circuit
and, simultaneously, the pole faces of the bottom and upper yokes shall be aligned accurately.
To minimize the effects of pressure on the test specimen, the upper yoke shall be provided with
a means of suspension. The suspension of the upper yoke shall allow part of its weight to be
counterbalanced so as to give a force on the test specimen of between 100 N and 200 N.
NOTE The square configuration of the yoke has been chosen in order to have only one test specimen for non-
oriented material. By rotating the test specimen through 90°, it is possible to determine the characteristics in the
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IEC 60404-3:2022 © IEC 2022 – 9 –
Dimensions in millimetres
Figure 2 – Yoke dimensions
4.3.2 Windings
The coil system inside the yokes shall have two windings:
– a primary winding, on the outside (magnetizing winding);
– a secondary winding, on the inside (voltage winding);
The primary (outer) and secondary (inner) windings shall be at least 440 mm in length and shall
be wound uniformly on a non-conducting, non-magnetic and rectangular former. Thedimensions of the former shall be as follows:
– length: 445 mm ± 2 mm;
– internal width: 510 mm ± 1 mm;
– internal height: 5 mm;
– height: ≤ 15 mm.
The primary winding can be made up of:
– either five or more coils having identical dimensions and the same number of turns
connected in parallel and taking up the whole length (see Figure 3). For example, with five
coils, each coil can be made up of 400 turns of copper wire 1 mm in diameter, wound in five
layers;– or a single continuous and uniform winding taking up the whole length. For example, this
winding can be made up of 400 turns of copper wire 1 mm in diameter, wound in one layer.
Figure 3 – Diagram of the connections of the five coils of the primary windingThe number of turns on the secondary winding will depend on the characteristics of the
measuring instruments. In any case, the determination of the number of turns of the primary
and secondary windings shall be made with gre...
SLOVENSKI STANDARD
oSIST prEN IEC 60404-3:2022
01-april-2022
Magnetni materiali - 3. del: Metode merjenja magnetnih lastnosti električnih
jeklenih trakov in pločevine z uporabo enolistnega preskuševalnika
Magnetic materials - Part 3: Methods of measurement of the magnetic properties of
electrical steel strip and sheet by means of a single sheet testerTa slovenski standard je istoveten z: prEN IEC 60404-3:2022
ICS:
17.220.20 Merjenje električnih in Measurement of electrical
magnetnih veličin and magnetic quantities
29.030 Magnetni materiali Magnetic materials
oSIST prEN IEC 60404-3:2022 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN IEC 60404-3:2022
68/699/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 60404-3 ED3
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2022-01-28 2022-04-22
SUPERSEDES DOCUMENTS:
68/687/CD, 68/696/CC
IEC TC 68 : MAGNETIC ALLOYS AND STEELS
SECRETARIAT: SECRETARY:
Germany Mr Richard Daniel Knobloch
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:
Other TC/SCs are requested to indicate their interest, if any,
in this CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel votingThe attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft for
Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.
This document is still under study and subject to change. It should not be used for reference purposes.
Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of which they
are aware and to provide supporting documentation.TITLE:
Magnetic materials - Part 3: Methods of measurement of the magnetic properties of electrical steel strip
and sheet by means of a single sheet testerPROPOSED STABILITY DATE: 2027
NOTE FROM TC/SC OFFICERS:
This Committee Draft for Vote was prepared by the responsible Project Leader and Team on the basis of the last
CD, 68/687CD, and the comments received from National Committees which are listed together with the
observations in 68/696/CC.National Committees are invited to send their comments and vote on this document.
Copyright © 2022 International Electrotechnical Commission, IEC. All rights reserved. It is permitted to download this
electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.
You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other purpose without
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1 CONTENTS
2 FOREWORD ........................................................................................................................... 4
3 1 Scope ............................................................................................................................... 6
4 2 Normative references ....................................................................................................... 6
5 3 Terms and definitions 6
6 4 General principles of AC measurements ........................................................................... 7
7 4.1 General ................................................................................................................... 7
8 4.2 Principle of the Single Sheet Tester method ............................................................ 7
9 4.3 Test apparatus ........................................................................................................ 7
10 4.3.1 Yokes .......................................................................................................... 7
11 4.3.2 Windings ..................................................................................................... 9
12 4.4 Air flux compensation ............................................................................................ 10
13 4.5 Test specimen ....................................................................................................... 10
14 4.6 Power supply ………………………………………………………………………………….1115 5 Determination of the specific total loss ........................................................................... 11
16 5.1 Principle of measurement ...................................................................................... 11
17 5.2 Apparatus ............................................................................................................. 11
18 5.2.1 Voltage measurement ................................................................................ 11
19 5.2.2 Frequency measurement ........................................................................... 12
20 5.2.3 Power measurement .................................................................................. 12
21 5.3 Measurement procedure of the specific total loss .................................................. 12
22 5.3.1 Preparation of measurement ..................................................................... 12
23 5.3.2 Adjustment of power supply ......................................................................... 12
24 5.3.3 Measurements ........................................................................................... 13
25 5.3.4 Reproducibility of the measurement of the specific totel loss ..................... 13
26 6 Determination of magnetic field strength, primary current and specific apparent power .. 14
27 6.1 General …………………………………………………………………………………………1428 6.2 Principle of measurement ………………………………………………………………….…….14
29 6.2.1 Peak value of magnetic polarization .......................................................... 14
30 R.M.S. value of the primary current ........................................................... 14
6.2.231 6.2.3 Peak value of the magnetic field strength .................................................. 14
32 6.3 Apparatus ............................................................................................................. 15
33 6.3.1 Average type voltmeter .............................................................................. 15
34 6.3.2 Current measurement ................................................................................ 15
35 6.3.3 Peak current measurement ........................................................................ 15
36 Power supply ............................................................................................. 15
6.3.437 6.3.5 Resistor R ............................................................................................... 15
38 6.4 Measuring procedure ............................................................................................ 15
39 6.4.1 Preparation for measurement .................................................................... 15
40 Measurement ............................................................................................ 16
6.4.241 6.4.3 Non-oriented material ................................................................................ 16
42 6.5 Determination of characteristics ............................................................................ 16
43 6.5.1 Determination of Ĵ ..................................................................................... 16
44 6.5.2 Determination of H ..................................................................................... 17
45 6.5.3 Determination of H ..................................................................................... 17
46 6.5.4 Determination of S ................................................................................... 17
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47 6.5.5 Reproducibility of the measurement of the apparent power S
s ……………….1848 7 Test Report .................................................................................................................... 18
49 Annex A (normative) Requirements concerning the manufacture of yokes ……………………..19
50 Annex B (informative) Check and verification of reliable performance of the SST- setup by the
51 use of reference samples and impact of the loss dissipated in the yokes ........................ 21
52 Annex C (informative) Epstein to SST relationship for grain-oriented sheet steel ................ 23
53 Annex D (informative) Digital sampling methods for the determination of the magnetic
54 properties and numerical air flux compensation .............................................................. 26
55 Bibliography........................................................................................................................ 30
56 Figure 1 – Schematic diagrammes of the test apparatus; Cross section of the SST (a) and
57 schematic view of the corner of a yoke with stacked lamination (b) ……………….….…………..8
58 Figure 2 – Yoke dimensions .................................................................................................... 9
59 Figure 3 – Diagram of the connections of the five coils of the primary winding ........................ 9
60 Figure 4 – Circuit for the determination of the specific total loss ........................................... 10
61 Figure 5 – Circuit for measuring the r.m.s. value of the primary current ................................ 14
62 Figure 6 – Circuit for measuring the peak value of the magnetic field strength ...................... 15
63 Figure B.1 - Specific loss vs. peak flux density (after J.Sievert [9] and F.Fiorillo [12]);
1.8564 straight line: P ∝ J approximation (after C.Ragusa)…………………………………………… 21
66 Figure C.1 – SST-Epstein relative difference δP for grain-oriented material versus magnetic
67 polarization J ……………………………………………………………………………………………. 2569 Figure C.2 – SST-Epstein rtelative difference δHS for grain-oriented material versus magnetic
70 polarization J……………………………………………………………………………………………….2572 Table B.1 Loss dissipated in the yokes of an standard SST determined from the loss curves
73 measured on 3 yoke pairs as shown in Figure B.1, and relevant quantities including the
74 relative yokes’ contribution, p ; exemplified using 5 standard grades………………………….. 22
76 Table C.1 – SST-Epstein relative differences δP and δHS and the conversion factor FC for
77 (conventional) grain-oriented material in the polarization range 1,0 T to 1,8 T ………………. 24
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79 INTERNATIONAL ELECTROTECHNICAL COMMISSION
80 ____________
82 MAGNETIC MATERIALS –
84 Part 3: Methods of measurement of the magnetic properties
85 of electrical steel strip and sheet by means
86 of a single sheet tester
90 FOREWORD
91 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national
92 electrotechnical committees (IEC National Committees). The object of IEC is to promote international co-operation on all
93 questions concerning standardization in the electrical and electronic fields. To this end and in addition to other activities,
94 IEC publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specifications
95 (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is entrusted to technical committees;
96 any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International,
97 governmental and non-governmental organizations liaising with the IEC also participate in this preparation. IEC
98 collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined
99 by agreement between the two organizations.100 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international consensus
101 of opinion on the relevant subjects since each technical committee has representation from all interested IEC National
102 Committees.103 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees
104 in that sense. While all reasonable efforts are made to ensure that the technical content of IEC Publications is accurate,
105 IEC cannot be held responsible for the way in which they are used or for any misinterpretation by any end user.
106 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently
107 to the maximum extent possible in their national and regional publications. Any divergence between any IEC Publication
108 and the corresponding national or regional publication shall be clearly indicated in the latter.
109 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity assessment
110 services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any services carried out by
111 independent certification bodies.112 6) All users should ensure that they have the latest edition of this publication.
113 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and members of
114 its technical committees and IEC National Committees for any personal injury, property damage or other damage of any
115 nature whatsoever, whether direct or indirect, or for costs (including legal fees) and expenses arising out of the publication,
116 use of, or reliance upon, this IEC Publication or any other IEC Publications.
117 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable
118 for the correct application of this publication.119 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights.
120 IEC shall not be held responsible for identifying any or all such patent rights.
121 International Standard IEC 60404-3 has been prepared by IEC technical committee 68: Magnetic alloys
122 and steels.123 This revised version of IEC 60404-3 was prepared on the basis of the consolidated edition 60404-3
124 Ed.2.2 which was modified introducing the following changes:125 The text of the main part was revised, leaving the substantial technical contents unchanged;
126 Annex A forms an integral part of this standard. The method of determining the yokes’ lamination
127 resistance was added to Annex A.128 Annex B of Ed.2.2 referred to calibration of the SST using the Epstein method. It was cancelled.
129 Annex B (new), C and D were revised, they are for information only.130 Annex C was modified taking account of the new situation regarding P and R grades.
131 Annex D was amended by addition of sub-clause D.4 on the numerical air flux compensation
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132 The committee has decided that the contents of the base publication and its amendments will remain
133 unchanged until the maintenance result date indicated on the IEC web site under
134 "http://webstore.iec.ch" in the data related to the specific publication. At this date, the publication will
135 be136 • reconfirmed,
137 • withdrawn,
138 • replaced by a revised edition, or
139 • amended.
140
141
142
143
144
145
146
147
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148 MAGNETIC MATERIALS –
149
150 Part 3: Methods of measurement of the magnetic properties
151 of electrical steel strip and sheet by means
152 of a single sheet tester
153
154
155
156 1 Scope
157 This part of IEC 60404 is applicable to grain-oriented and non-oriented electrical steel strip and sheet
158 for measurement of AC magnetic properties at power frequencies.159
160 The object of this document is to define the general principles and the technical details of the
161 measurement of the magnetic properties of electrical steel strip and sheet by means of a single sheet
162 tester (SST).163 The single sheet tester is applicable to test specimens obtained from electrical strips and sheets of
164 any grade. The AC magnetic characteristics are determined for sinusoidal induced voltages, for
165 specified peak values of the magnetic polarization, for specific peak values of the magnetic field
166 strength and for a specified frequency.167 The measurements are made at an ambient temperature of 23 °C ± 5 °C on test specimens which have
168 first been demagnetized.169 NOTE Throughout this part the quantity "magnetic polarization" is used as defined in IEC 60050-221. In some standards of
170 the IEC 60404 series, the quantity "magnetic flux density" was used.171
172 2 Normative references
173 The following documents are referred to in the text in such a way that some or all of their content
174 constitutes requirements of this document. For dated references, only the edition cited applies. For
175 undated references, the latest edition of the referenced document (including any amendments) applies.
176 IEC 60050-121, International Electrotechnical Vocabulary – Part 121: Electromagnetism
177 IEC 60050-221, International Electrotechnical Vocabulary – Part 221: Magnetic materials and
178 components179 IEC 60404-13, Magnetic materials – Part 13: Methods of measurement of resistivity, density and
180 stacking factor of electrical steel strip and sheet181 3 Terms and definitions
182 For the purposes of this document, the terms and definitions given in IEC 60050-121 and IEC 60050-
183 221 apply.184 ISO and IEC maintain terminological databases for use in standardization at the following addresses:
185 IEC Electropedia: available at http://www.electropedia.org/186 ISO Online browsing platform: available at http:www.iso.org/obp
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187 4 General principles of AC measurements
188 4.1 General
189 Clause 4 specifies the general conditions for the determination of AC magnetic properties of electrical
190 steel strip and sheet at power frequencies by means of a single sheet tester.
191 4.2 Principle of the single sheet tester method192 The test specimen comprises a sample of electrical steel sheet and is placed in the center of two
193 concentric windings:194 – an exterior primary winding (magnetizing winding);
195 – an interior secondary winding (voltage winding).
196 The flux closure is made by a magnetic circuit consisting of two identical yokes, the cross-section of
197 which is very large compared with that of the test specimen (see Figure 1).198 Care shall be taken to ensure that the temperature changes of the specimen are kept below a level
199 likely to produce stress in the test specimen due to thermal expansion or contraction.
200 4.3 Test apparatus201 4.3.1 Yokes
202 Each yoke is in the form of a U made up of insulated sheets of grain-oriented electrical steel. It shall
203 have a low reluctance and a low specific total loss in the low magnetic polarization region below 0,1 T.
204 (see Annex A). It shall be manufactured in accordance with the requirements of Annex A.
205 In order to reduce the effect of eddy currents and give a more homogeneous distribution of the flux
206 over the inside of the yokes, the latter shall be made of a pair of wound cut C-cores or a glued stack
207 of laminations in which case the corners shall have staggered butt joints (see Figure 1).
208 The yoke shall have pole faces having a width of 25 mm ± 1 mm.209 The two pole faces of each yoke shall be coplanar to within 0,5 mm and the gap between the opposite
210 pole faces of the yokes shall not exceed 0,005 mm at any point. Also, the yokes shall be rigid in order
211 to avoid creating mechanical stresses in the test specimen.212 The height of each yoke shall be between 90 mm and 150 mm. Each yoke shall have a width of 500
213 mm and an inside length of 450 mm ± 1 mm (see Figure 2).214 There shall be a non-conducting, non-magnetic support on which the test specimen is placed, between
215 the vertical limbs of the bottom yokes. This support shall be centered and located in the same plane
216 as the bottom yoke pole faces so that the test specimen is in direct contact with the pole faces without
217 any gap. Care shall be taken that in no case the upper surface of the support is positioned higher than
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219
220 (a)
221
222 (b)
223
224 Figure 1 – Schematic diagrammes of the test apparatus; Cross section of the SST (a) and
225 schematic view of the corner of a yoke with stacked lamination (b)226 The upper yoke shall be movable upwards to permit insertion of the test specimen. After insertion of
227 the test specimen the upper yoke shall be lowered to close the magnetic circuit and, simultaneously,
228 the pole faces of the bottom and upper yokes shall be aligned accurately. To minimize the effects of
229 pressure on the test specimen, the upper yoke shall be provided with a means of suspension. The
230 suspension of the upper yoke shall allow part of its weight to be counterbalanced so as to give a force
231 on the test specimen of between 100 N and 200 N.232 NOTE The square configuration of the yoke has been chosen in order to have only one test specimen for non-oriented
233 material. By rotating the test specimen through 90° it is possible to determine the characteristics in the rolling direction and
234 perpendicular to the rolling direction.235
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236
237 Figure 2 – Yoke dimensions
238
239 4.3.2 Windings
240 The coil system inside the yokes shall have two windings:
241 – a primary winding, on the outside (magnetizing winding);
242 – a secondary winding, on the inside (voltage winding);
243 The primary (outer) and secondary (inner) windings shall be at least 440 mm in length and shall
244 be wound uniformly on a non-conducting, non-magnetic and rectangular former. The dimensions of
245 the former shall be as follows:246 – length: 445 mm ± 2 mm;
247 – internal width: 510 mm ± 1 mm;
0
248 mm;
– internal height: 5
249 – height: ≤15 mm.
250 The primary winding can be made up of:
251 – either five or more coils having identical dimensions and the same number of turns connected in
252 parallel and taking up the whole length (see Figure 3). For example, with five coils, each coil can
253 be made up of 400 turns of copper wire 1 mm in diameter, wound in five layers;
254 – or a single continuous and uniform winding taking up the whole length. For example this winding
255 can be made up of 400 turns of copper wire 1 mm in diameter, wound in one layer.
256257 Figure 3 – Diagram of the connections of the five coils of the primary winding
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259 The number of turns on the secondary winding will depend on the characteristics of the measuring
260 instruments. In any case, the determination of the number of turns of the primary and secondary
261 windings shall be made with greatest reliability because a mistake would mean a permanent error.
262 4.4 Air flux compensation263 Compensation shall be made for the effect of air flux. This can be achieved, for example, by a mutual
264 inductor M (see Figure 4). The primary winding of the mutual inductor is connected in series with the
265 primary winding of the test apparatus, while the secondary winding of the mutual inductor is connected
266 to the secondary winding of the test apparatus in series opposition.267
268 Key
269 V1 measures the average rectified voltage
270 V2 measures the r.m.s. voltage
271 A measures the r.m.s. value of the primary current
272 Hz measures the frequency
273 W measures the power
274 M is the mutual inductor
275 T is the test frame
276
277 Figure 4 – Circuit for the determination of the specific total loss
278
279 The adjustment of the value of the mutual inductance shall be made so that when passing an alternating
280 current through the primary windings in the absence of the test specimen in the test apparatus, the
281 voltage measured between the non-common terminals of the secondary windings shall be no more than
282 0,1 % of the voltage appearing across the secondary winding of the test apparatus alone. Thus the
283 average value of the rectified voltage induced in the combined secondary windings is proportional to
284 the peak value of the magnetic polarization in the test specimen.285 NOTE 1 Alternatively, the air flux compensation can be executed by the numerical method (for details see Annex D,
286 Clause D.4).287 NOTE 2 In the rest of this document the term “compensated secondary voltage” is used to mean “voltage induced in the
288 secondary winding compensated for the effect of air flux”.289
290 4.5 Test specimen
291 The length of the test specimen shall be not less than 500 mm. Although the part of the test specimen
292 situated outside the pole faces has no great influence on the measurement, this part shall not be longer
293 than is necessary to facilitate insertion and removal of the test specimen.294 The width of the test specimen shall be as large as possible and at its maximum equal to the width of
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296 For optimum accuracy, the minimum width shall be not less than 60 % of the width of the yokes.
297 NOTE 1 Specific restrictions of the dimensions of the test specimens can be defined for special material grades in the
298 respective product standards for magnetic materials.299
300 NOTE 2 Information about application of the SST to strip samples of 50 mm to 250 mm width: Grain-oriented electrical steel
301 used for distribution transformer (DT) cores is merchandized in the form of slit coils of 50 mm to 250 mm width cut from the
302 as produced steel strips (master coils) at the different positions across the original strips. The slit coils reflect the
303 considerable variation of the material properties corresponding to the position on the original strip, where they have been
304 cut from. These small strip specimens can be measured using this SST placing them side by side or with distributed gaps in
305 the SST. In order to attain a relevant measurement result a minimum of 60 % of the 500 mm wide sample space needs to be
306 filled with strips. The test strip samples may be taken successively from the start or the end of a slit coil. When preparing
307 them taking care would avoid any damage which could influence the test result. Due to the cutting of the sheet into the small
308 strips, the measured loss of narrow strips will be slightly increased compared to the original 500 mm.
309310 The test specimen shall be cut without the formation of excessive burrs or mechanical distortion. The
311 test specimen shall be plane. When a test specimen is cut, the edge of the parent strip is taken as
312 the reference direction. The angle between the direction of rolling and that of cutting shall not
313 exceed:314 ±1° for grain oriented steel sheet;
315 ±5° for non-oriented steel sheet.
316 For non-oriented steel sheet, two specimens shall be cut, one parallel to the direction of rolling and the
317 other perpendicular unless the test specimen is square, in which case one test specimen only is
318 necessary.319 4.6 Power supply
320 The power supply shall be of low internal impedance and shall be highly stable in terms of voltage and
321 frequency. During the measurement, the voltage and the frequency shall be maintained constant within
322 ±0,2 %.323 In addition, the waveform of the compensated secondary voltage shall be maintained as sinusoidal as
324 possible. The form factor of the compensated secondary voltage shall be maintained to within ±1 % of
325 1,111. This can be achieved by various means, for example by using an electronic feedback amplifier
326 or by a computational digital feedback system.327 5 Determinat
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