IEC 63093-8:2018

Ferrite cores - Guidelines on dimensions and the limits of surface irregularities - Part 8: E-cores

IEC 63093-8:2018 specifies the dimensions that are of importance for mechanical interchangeability for a preferred range of E-cores made of ferrite and the essential dimensions of coil formers to be used with them, as well the effective parameter values to be used in calculations involving them. It also gives guidelines on allowable limits of surface irregularities applicable to E-cores.
The specifications contained in this document are useful in negotiations between ferrite core manufacturers and customers about surface irregularities. The use of derived standards, which give more detailed specifications of component parts while still permitting compliance with this standard, is discussed in Annex A.
This edition includes the following significant technical changes with respect to IEC 62317-­8:2006 and IEC 60424-3:2015:
a. This document integrates IEC 62317-8:2006 and IEC 60424-3:2015;
b. Table 4 – Allowable areas of chips for E-cores, of IEC 60424-3:2015, has been moved to Annex C (informative) of this document.

Noyaux ferrites – Lignes directrices relatives aux dimensions et aux limites des irrégularités de surface – Partie 8: Noyaux E

L'IEC 63093-8:2018 spécifie les dimensions qui jouent un rôle majeur dans l'interchangeabilité mécanique d'une gamme préférentielle de noyaux E constitués de ferrites et les dimensions essentielles des carcasses à utiliser avec ces noyaux, ainsi que les valeurs des paramètres effectifs à utiliser dans les calculs qui les impliquent. Elle donne également les lignes directrices relatives aux limites admissibles des irrégularités de surface applicables aux noyaux E.
Les spécifications du présent document sont utiles aux négociations entre les fabricants de noyaux en ferrite et leurs clients concernant les irrégularités de surface.
Cette première édition annule et remplace la première édition de l'IEC 62317-8 parue en 2006 et la deuxième édition de l'IEC 60424-3 parue en 2015. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'IEC 62317­8:2006 et l'IEC 60424-3:2015:
a) le présent document intègre l'IEC 62317-8:2006 et l'IEC 60424­3:2015;
b) le Tableau 4 – Surfaces admissibles des éclats pour les noyaux E, de l'IEC 60424-3:2015, a été déplacé à l'Annexe C (informative) du présent document.

General Information

• Status: Published
• Publication Date: 26-Jun-2018
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.100.10 - Magnetic components
• Technical Committee: TC 51 - Magnetic components, ferrite and magnetic powder materials
• Drafting Committee: WG 1 - TC 51/WG 1
• Current Stage: PPUB - Publication issued
• Start Date: 27-Jun-2018
• Completion Date: 25-Jul-2018

Relations

• Replaces: IEC 62317-8:2006 - Ferrite cores - Dimensions - Part 8: E-cores
• Effective Date: 05-Sep-2023
• Replaces: IEC 60424-3:2015 - Ferrite cores - Guidelines on the limits of surface irregularities - Part 3: ETD-cores, EER-cores, EC-cores and E-cores
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 63093-8 ®
Edition 1.0 2018-06
INTERNATIONAL
STANDARD
Ferrite cores – Guidelines on dimensions and the limits of surface
irregularities –
Part 8: E-cores
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.

IEC Central Office Tel.: [phone]
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Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
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IEC 63093-8 ®
Edition 1.0 2018-06
INTERNATIONAL
STANDARD
Ferrite cores – Guidelines on dimensions and the limits of surface

irregularities –
Part 8: E-cores
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.100.10 ISBN 978-2-8322-5835-4

– 2 – IEC 63093-8:2018 © IEC 2018
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Primary dimensions . 6
4.1 General . 6
4.2 Dimensions of E-cores . 7
4.2.1 Main dimensions . 7
4.2.2 Effective parameter and A values . 9
min
4.3 Dimensional limits for coil formers . 11
5 Limits of surface irregularities . 15
5.1 General . 15
5.2 Examples of surface irregularities . 15
5.3 Chips and ragged edges . 15
5.3.1 General . 15
5.3.2 Chips and ragged edges on the mating surfaces . 15
5.3.3 Chips and ragged edges on the other surfaces . 15
5.4 Cracks . 18
5.5 Flash . 18
5.6 Pull-outs . 18
5.7 Crystallites . 19
5.8 Pores . 19
Annex A (normative) Derived standards . 21
Annex B (normative) Example of dimensions for gauges to check the dimensions of
E-cores complying with this document . 22
B.1 General . 22
B.2 Procedure and requirements . 24
Annex C (informative) Reference of allowable areas of chips . 25
Bibliography . 26

Figure 1 – Dimensions of E-cores with rectangular cross-section . 7
Figure 2 – Main dimensions of coil formers . 12
Figure 3 – Examples of surface irregularities . 15
Figure 4 – Chip location for E-cores . 16
Figure 5 – Crack and pull-out locations for E-cores . 18
Figure 6 – Crystallite location for E-cores . 19
Figure 7 – Pore location for E-cores . 20
Figure B.1 – Gauge dimensions . 22

Table 1 – Dimensions of E-cores with rectangular cross-section . 8
Table 2 – Effective parameter and A values . 10
min
Table 3 – Dimensional limits for coil formers . 13
Table 4 – Area and length reference for visual inspection . 17
Table 5 – Limits for cracks . 19

Table B.1 – Gauge dimensions . 23
Table C.1 – Allowable areas of chips for E-cores . 25

– 4 – IEC 63093-8:2018 © IEC 2018
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FERRITE CORES – GUIDELINES ON DIMENSIONS
AND THE LIMITS OF SURFACE IRREGULARITIES –

Part 8: E-cores
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 63093-8 has been prepared by IEC technical committee 51:
Magnetic components, ferrite and magnetic powder materials.
This first edition cancels and replaces the first edition of IEC 62317-8 published in 2006 and
the second edition of IEC 60424-3 published in 2015. This edition constitutes a technical
revision.
This edition includes the following significant technical changes with respect to
IEC 62317-8:2006 and IEC 60424-3:2015:
a) This document integrates IEC 62317-8:2006 and IEC 60424-3:2015;
b) Table 4 – Allowable areas of chips for E-cores, of IEC 60424-3:2015, has been moved to
Annex C (informative) of this document.

The text of this International Standard is based on the following documents:
CDV Report on voting
51/1213/CDV 51/1235/RVC
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.
A list of all parts in the IEC 63093 series, published under the general title Ferrite cores –
Guidelines on dimensions and the limits of surface irregularities, 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.
A bilingual version of this publication may be issued at a later date.

– 6 – IEC 63093-8:2018 © IEC 2018
FERRITE CORES – GUIDELINES ON DIMENSIONS
AND THE LIMITS OF SURFACE IRREGULARITIES –

Part 8: E-cores
1 Scope
This part of IEC 63093 specifies the dimensions that are of importance for mechanical
interchangeability for a preferred range of E-cores made of ferrite and the essential
dimensions of coil formers to be used with them, as well the effective parameter values to be
used in calculations involving them. It also gives guidelines on allowable limits of surface
irregularities applicable to E-cores.
The specifications contained in this document are useful in negotiations between ferrite core
manufacturers and customers about surface irregularities.
The use of derived standards, which give more detailed specifications of component parts
while still permitting compliance with this standard, is discussed in Annex A.
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 60205, Calculation of the effective parameters of magnetic piece parts
IEC 60401-1, Terms and nomenclature for cores made of magnetically soft ferrites – Part 1:
Terms used for physical irregularities
IEC 60424-1, Ferrite cores – Guidelines on the limits of surface irregularities – Part 1:
General specification
3 Terms and definitions
For the purpose of this document, the terms and definitions given in IEC 60401-1 and
IEC 60424-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 Primary dimensions
4.1 General
Compliance with the following requirements ensures mechanical interchangeability of
complete assemblies and coil formers.

4.2 Dimensions of E-cores
4.2.1 Main dimensions
The main dimensions of E-cores with rectangular cross-section shall be those given in Table 1.
The dimensions of the cores can be checked by means of gauges, an example of which is
given in Annex B. In order to facilitate production it can be necessary to use gauges with
dimensions differing from those given in Annex B, although no relaxation of the requirements
for the dimensions of the cores given in Table 1 is thereby permitted. The dimensions
specified in Table 1 are illustrated in Figure 1.
B
D C
IEC
Figure 1 – Dimensions of E-cores with rectangular cross-section

F
E
A
– 8 – IEC 63093-8:2018 © IEC 2018

Table 1 – Dimensions of E-cores with rectangular cross-section
A B C D E F
a
IEC 61246 Industrial
Size mm mm mm mm mm mm
references references
Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max.
E5,3/2 5,15 5,35 2,57 2,73 1,90 2,00 1,92 2,08 3,80 4,00 1,30 1,40 E5,3/2 FEE5,25; EE5
E6,3/2 6,05 6,30 2,80 2,90 1,90 2,00 1,85 2,05 3,60 3,80 1,30 1,40 E6,3/2 FEE6,18
E8/2 7,85 8,15 3,95 4,05 2,30 2,40 2,85 2,95 5,60 5,80 2,30 2,40 E8/2 FEE8
E8,3/4 8,10 8,60 3,90 4,10 3,40 3,80 2,90 3,10 6,10 6,50 1,60 2,00 FEE8,3; EE8
E8,8/2 8,60 9,40 3,85 4,15 1,78 2,02 2,03 2,40 5,07 5,33 1,78 2,02 E8,8/2 FEE9
E10/3 9,80 10,2 4,88 5,00 2,88 3,00 3,50 3,62 7,00 7,30 2,88 3,00 E10/3 FEE10
E10,2/5 10,0 10,5 5,35 5,65 4,50 4,90 4,05 4,35 7,60 8,00 2,20 2,60 FEE10,2; EE10/11
E13/4 12,2 13,1 6,30 6,50 3,40 3,70 4,50 4,80 8,90 9,50 3,40 3,70 E13/4 FEE12,7A; EF12,6
E13/6 12,8 13,2 5,85 6,15 6,00 6,30 4,50 4,70 10,0 10,4 2,60 2,90 EE13
E16/4,8 15,7 16,3 7,00 7,30 4,60 5,00 5,00 5,40 11,7 12,3 3,80 4,20 FEE16A; EE16
E16/5 15,5 16,7 7,90 8,20 4,30 4,70 5,70 6,10 11,3 11,9 4,40 4,70 E16/5 FEE16,1; EF16
E19/5 18,6 19,4 7,80 8,20 4,80 5,20 5,40 5,80 14,2 14,8 4,30 4,70 FEE19A; EE19
E19,3/4,8 18,97 19,61 7,92 8,28 4,63 4,88 5,59 5,84 14,05 14,7 4,67 4,83 EE-187; EE19/16
E20/6 19,4 20,8 9,80 10,2 5,40 5,90 7,00 7,40 14,1 14,7 5,50 5,90 E20/6 FEE20,1; EF20
E25/7 24,3 25,8 12,3 12,8 6,90 7,50 8,70 9,20 17,5 18,3 7,00 7,50 E25/7 FEE25,1; EF25
E25,4/6 24,9 25,9 9,30 9,70 6,05 6,65 6,20 6,60 18,6 19,4 6,05 6,65 FEE25,4A
E25,4/6,3 24,9 25,9 9,27 9,65 6,10 6,48 6,22 6,60 18,55 19,81 6,10 6,60 EE24/25; EE25/19
E30/11 29,5 30,6 12,9 13,5 10,4 11,0 7,90 8,50 19,5 20,5 10,4 11,0 FEE30A; EE30
E32/9 31,3 32,9 15,8 16,4 8,80 9,50 11,2 11,8 22,7 23,7 8,90 9,50 E32/9 FEE32,1; EF32
E33/13 32,5 33,9 13,5 14,1 12,4 13,0 9,00 9,60 23,1 24,1 9,40 10,0 FEE33A; EE33
E34,6/9 33,9 35,3 13,9 14,64 8,90 9,72 9,51 10,05 25,0 26,2 9,10 9,70 EE375; EE35/28B
E35/10 34,5 35,7 15,2 15,8 9,70 10,3 9,20 9,80 24,5 25,5 9,70 10,3 FEE
...

IEC 63093-8 ®
Edition 1.0 2018-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Ferrite cores – Guidelines on dimensions and the limits of surface
irregularities –
Part 8: E-cores
Noyaux ferrites – Lignes directrices relatives aux dimensions et aux limites
des irrégularités de surface –
Partie 8: Noyaux E
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IEC 63093-8 ®
Edition 1.0 2018-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Ferrite cores – Guidelines on dimensions and the limits of surface

irregularities –
Part 8: E-cores
Noyaux ferrites – Lignes directrices relatives aux dimensions et aux limites

des irrégularités de surface –

Partie 8: Noyaux E
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.100.10 ISBN 978-2-8322-1088-6

– 2 – IEC 63093-8:2018 © IEC 2018
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Primary dimensions . 6
4.1 General . 6
4.2 Dimensions of E-cores . 7
4.2.1 Main dimensions . 7
4.2.2 Effective parameter and A values . 9
min
4.3 Dimensional limits for coil formers . 11
5 Limits of surface irregularities . 15
5.1 General . 15
5.2 Examples of surface irregularities . 15
5.3 Chips and ragged edges . 15
5.3.1 General . 15
5.3.2 Chips and ragged edges on the mating surfaces . 15
5.3.3 Chips and ragged edges on the other surfaces . 15
5.4 Cracks . 18
5.5 Flash . 18
5.6 Pull-outs . 18
5.7 Crystallites . 19
5.8 Pores . 19
Annex A (normative) Derived standards . 21
Annex B (normative) Example of dimensions for gauges to check the dimensions of
E-cores complying with this document . 22
B.1 General . 22
B.2 Procedure and requirements . 24
Annex C (informative) Reference of allowable areas of chips . 25
Bibliography . 26

Figure 1 – Dimensions of E-cores with rectangular cross-section . 7
Figure 2 – Main dimensions of coil formers . 12
Figure 3 – Examples of surface irregularities . 15
Figure 4 – Chip location for E-cores . 16
Figure 5 – Crack and pull-out locations for E-cores . 18
Figure 6 – Crystallite location for E-cores . 19
Figure 7 – Pore location for E-cores . 20
Figure B.1 – Gauge dimensions . 22

Table 1 – Dimensions of E-cores with rectangular cross-section . 8
Table 2 – Effective parameter and A values . 10
min
Table 3 – Dimensional limits for coil formers . 13
Table 4 – Area and length reference for visual inspection . 17
Table 5 – Limits for cracks . 19

Table B.1 – Gauge dimensions . 23
Table C.1 – Allowable areas of chips for E-cores . 25

– 4 – IEC 63093-8:2018 © IEC 2018
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FERRITE CORES – GUIDELINES ON DIMENSIONS
AND THE LIMITS OF SURFACE IRREGULARITIES –

Part 8: E-cores
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 63093-8 has been prepared by IEC technical committee 51:
Magnetic components, ferrite and magnetic powder materials.
This first edition cancels and replaces the first edition of IEC 62317-8 published in 2006 and
the second edition of IEC 60424-3 published in 2015. This edition constitutes a technical
revision.
This edition includes the following significant technical changes with respect to
IEC 62317-8:2006 and IEC 60424-3:2015:
a) This document integrates IEC 62317-8:2006 and IEC 60424-3:2015;
b) Table 4 – Allowable areas of chips for E-cores, of IEC 60424-3:2015, has been moved to
Annex C (informative) of this document.

The text of this International Standard is based on the following documents:
CDV Report on voting
51/1213/CDV 51/1235/RVC
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.
A list of all parts in the IEC 63093 series, published under the general title Ferrite cores –
Guidelines on dimensions and the limits of surface irregularities, 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.
– 6 – IEC 63093-8:2018 © IEC 2018
FERRITE CORES – GUIDELINES ON DIMENSIONS
AND THE LIMITS OF SURFACE IRREGULARITIES –

Part 8: E-cores
1 Scope
This part of IEC 63093 specifies the dimensions that are of importance for mechanical
interchangeability for a preferred range of E-cores made of ferrite and the essential
dimensions of coil formers to be used with them, as well the effective parameter values to be
used in calculations involving them. It also gives guidelines on allowable limits of surface
irregularities applicable to E-cores.
The specifications contained in this document are useful in negotiations between ferrite core
manufacturers and customers about surface irregularities.
The use of derived standards, which give more detailed specifications of component parts
while still permitting compliance with this standard, is discussed in Annex A.
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 60205, Calculation of the effective parameters of magnetic piece parts
IEC 60401-1, Terms and nomenclature for cores made of magnetically soft ferrites – Part 1:
Terms used for physical irregularities
IEC 60424-1, Ferrite cores – Guidelines on the limits of surface irregularities – Part 1:
General specification
3 Terms and definitions
For the purpose of this document, the terms and definitions given in IEC 60401-1 and
IEC 60424-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 Primary dimensions
4.1 General
Compliance with the following requirements ensures mechanical interchangeability of
complete assemblies and coil formers.

4.2 Dimensions of E-cores
4.2.1 Main dimensions
The main dimensions of E-cores with rectangular cross-section shall be those given in Table 1.
The dimensions of the cores can be checked by means of gauges, an example of which is
given in Annex B. In order to facilitate production it can be necessary to use gauges with
dimensions differing from those given in Annex B, although no relaxation of the requirements
for the dimensions of the cores given in Table 1 is thereby permitted. The dimensions
specified in Table 1 are illustrated in Figure 1.
B
D C
IEC
Figure 1 – Dimensions of E-cores with rectangular cross-section

F
E
A
– 8 – IEC 63093-8:2018 © IEC 2018

Table 1 – Dimensions of E-cores with rectangular cross-section
A B C D E F
a
IEC 61246 Industrial
Size mm mm mm mm mm mm
references references
Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max.
E5,3/2 5,15 5,35 2,57 2,73 1,90 2,00 1,92 2,08 3,80 4,00 1,30 1,40 E5,3/2 FEE5,25; EE5
E6,3/2 6,05 6,30 2,80 2,90 1,90 2,00 1,85 2,05 3,60 3,80 1,30 1,40 E6,3/2 FEE6,18
E8/2 7,85 8,15 3,95 4,05 2,30 2,40 2,85 2,95 5,60 5,80 2,30 2,40 E8/2 FEE8
E8,3/4 8,10 8,60 3,90 4,10 3,40 3,80 2,90 3,10 6,10 6,50 1,60 2,00 FEE8,3; EE8
E8,8/2 8,60 9,40 3,85 4,15 1,78 2,02 2,03 2,40 5,07 5,33 1,78 2,02 E8,8/2 FEE9
E10/3 9,80 10,2 4,88 5,00 2,88 3,00 3,50 3,62 7,00 7,30 2,88 3,00 E10/3 FEE10
E10,2/5 10,0 10,5 5,35 5,65 4,50 4,90 4,05 4,35 7,60 8,00 2,20 2,60 FEE10,2; EE10/11
E13/4 12,2 13,1 6,30 6,50 3,40 3,70 4,50 4,80 8,90 9,50 3,40 3,70 E13/4 FEE12,7A; EF12,6
E13/6 12,8 13,2 5,85 6,15 6,00 6,30 4,50 4,70 10,0 10,4 2,60 2,90 EE13
E16/4,8 15,7 16,3 7,00 7,30 4,60 5,00 5,00 5,40 11,7 12,3 3,80 4,20 FEE16A; EE16
E16/5 15,5 16,7 7,90 8,20 4,30 4,70 5,70 6,10 11,3 11,9 4,40 4,70 E16/5 FEE16,1; EF16
E19/5 18,6 19,4 7,80 8,20 4,80 5,20 5,40 5,80 14,2 14,8 4,30 4,70 FEE19A; EE19
E19,3/4,8 18,97 19,61 7,92 8,28 4,63 4,88 5,59 5,84 14,05 14,7 4,67 4,83 EE-187; EE19/16
E20/6 19,4 20,8 9,80 10,2 5,40 5,90 7,00 7,40 14,1 14,7 5,50 5,90 E20/6 FEE20,1; EF20
E25/7 24,3 25,8 12,3 12,8 6,90 7,50 8,70 9,20 17,5 18,3 7,00 7,50 E25/7 FEE25,1; EF25
E25,4/6 24,9 25,9 9,30 9,70 6,05 6,65 6,20 6,60 18,6 19,4 6,05 6,65 FEE25,4A
E25,4/6,3 24,9 25,9 9,27 9,65 6,10 6,48 6,22 6,60 18,55 19,81 6,10 6,60 EE24/25; EE25/19
E30/11 29,5 30,6 12,9 13,5 10,4 11,0 7,90 8,50 19,5 20,5 10,4 11,0 FEE30A; EE30
E32/9 31,3 32,9 15,8 16,4 8,80 9,50 11,2 11,8 22,7 23,7 8,90 9,50 E32/9 FEE32,1; EF32
E33/13 32,5 33,9 13,5 14,1 12,4 13,0 9,00 9,60 23,1 24,1 9,40 10,0 FEE33A; EE33
E34,6/9 33,9 35,3 13,9 14,64 8,90 9,72 9,51 10,05 25,0 26,2 9,10 9,70 EE375; EE35/28B
E35/10 34,5 35,7 15,2 15,8 9,70 10,3 9,20 9,80 24,5 25,5 9,70 10,3 FEE35A; EE35
E40/11 39,5 40,7 16,7 17,3 10,4 11,0 10,0 10,6 27,5 28,5 9,70 11,0 FEE40A; EE40
E41/13 40,27 41,87 16,38 17,18 12,19 12,95 10,08 10,68 28,55 29,59 12,19 13,1 EE21; EE41/33C

A B C D E F
a
IEC 61246 Industrial
Size mm mm mm mm mm mm
references references
Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max.
E42/15 41,3 43,0 20,8 21,2 14,7 15,2 14,8 15,5 29,5 30,7 11,7 12,2 E42/15 FEE42A
E42/20 41,3 43,0 20,8 21,2 19,2 20,0 14,8 15,5 29,5 30,7 11,7 12,2 E42/20 FEE42B
E47/16 46,1 47,88 19,4 19,83 15,35 15,87 12,07 12,5 31,72 32,56 15,35 15,87 EE625; EE47/39
E50/15 49,3 51,0 21,0 21,6 14,2 15,0 12,5 13,1 34,3 35,7 14,2 15,0 EE50A; EE50
E55/21 54,1 56,2 27,2 27,8 20,4 21,0 18,5 19,3 37,5 38,7 16,7 17,2 E55/21 FEE55,2A
E55/25 54,1 56,2 27,2 27,8 24,2 25,0 18,5 19,3 37,5 38,7 16,7 17,2 E55/25 FEE55,2B
E60/16 59,2 61,1 22,0 22,6 15,2 16,0 13,7 14,0 43,7 45,3 15,2 16,0 FEE60A; EE60
E65/27 63,8 66,5 32,2 32,8 26,6 27,4 22,2 23,0 44,2 45,7 19,3 20,0 E65/27 FEE65,2
a
Withdrawn publication.
4.2.2 Effective parameter and A values
min
The effective parameter values of a pair of cores whose dimensions comply with 4.2.1 shall be as given in Table 2. For the definitions of these
parameters and their calculations, reference shall be made to IEC 60205.

– 10 – IEC 63093-8:2018 © IEC 2018

Table 2 – Effective parameter and A values
min
b
C C l A V A c
1 2 e e e min IEC 61246
a
Size Industrial references
−1 −3 2 3 2 references
mm mm mm mm mm mm
E5,3/2 4,850 4 1,863 0 12,6 2,60 32,9 2,54 B
E6,3/2 3,764 6 1,148 7 12,3 3,28 40,4 2,63 C E6,3/2 FEE6,18
E8/2 3,439 7 0,639 76 18,5 5,38 99,4 5,17 B E8/2 FEE8
E8,3/4 2,800 3 0,401 68 19,5 6,97 136 6,48 C FEE8,3; EE8
E8,8/2 3,154 0 0,635 22 15,7 4,97 77,8 3,61 C E8,8/2 FEE9
E10/3 2,726 6 0,324 93 22,9 8,40 192 8,11 B E10/3 FEE10
E10,2/5 2,250 3 0,193 83 26,1 11,6 303 11,3 C FEE10,2; EE10/11
E13/4 2,394 6 0,192 77 29,7 12,4 369 12,2 L E13/4 FEE12,7A; EF12,6
E13/6 1,766 3 0,103 21 30,2 17,1 517 16,9 C EE13
−2
FEE16A; EE16
E16/4,8 1,837 9 9,651 2 × 10 35,0 19,0 667 18,7 B
−2
E16/5 1,872 4 9,333 3 × 10 37,6 20,1 754 19,4 B E16/5 FEE16,1; EF16
−2
E19/5 1,726 4 7,512 0 × 10 39,7 23,0 912 22,5 C FEE19A; EE19
−2
EE-187; EE19/16
E19,3/4,8 1,751 0 7,661 8 × 10 40,0 22,9 914 22,6 C
−2
E20/6 1,447 3 4,516 8 × 10 46,4 32,0 1 490 31,6 B E20/6 FEE20,1; EF20
−2
E25/7 1,114 2 2,149 5 × 10 57,8 51,8 2 990 51,5 L E25/7 FEE25,1; EF25
−2
E25,4/6 1,198 6 48,1 40,2 1 930 39,4 B FEE25,4A
2,984 8 × 10
−2
EE24/25; EE25/19
E25,4/6,3 1,232 8 3,153 8 × 10 74,2 39,1 1 880 38,4 B
−3
E30/11 0,529 47 4,828 8 × 10 58,1 110 6 370 107 B FEE30A; EE30
−3
E32/9 0,893 64 74,3 83,2 6 180 81,4 L E32/9 FEE32,1; EF32
10,746 × 10
−3
FEE33A; EE33
E33/13 0,548 84 4,585 3 × 10 65,7 120 7 860 114 B
−3
E34,6/9 0,819 44 9,651 6 × 10 69,5 84,9 5 910 83,6 B EE375; EE35/28B
−3
E35/10 0,660 20 70,0 106 7 420 100 C FEE35A; EE35
6,229 0 × 10
−3
FEE40A; EE40
E40/11 0,606 50 4,749 4 × 10 77,5 128 9 890 114 C
−3
E41/13 0,495 37 3,161 1 × 10 77,6 157 12 200 151 L EE21; EE41/33C

b
C C l A V A c
1 2 e e e min IEC 61246
a
Size Industrial references
−1 −3 2 3 2 references
mm mm mm mm mm mm
−3
E42/15 0,546 63 3,069 3 × 10 97,4 178 17 300 175 B E42/15 FEE42A
−3
E42/20 0,416 95 1,785 7 × 10 97,4 233 22 700 229 B E42/20 FEE42B
−3
E47/16 0,379 69 89,1 235 20 900 229 B EE625; EE47/39
1,618 1 × 10
−3
EE50A; EE50
E50/15 0,425 62 1,880 2 × 10 96,3 226 21 800 213 C
−4
E55/21 0,350 12 9,917 4 × 10 124 353 43 600 350 C E55/21 FEE55,2A
−4
E55/25 0,294 62 124 420 51 900 417 C E55/25 FEE55,2B
7,022 1 × 10
−4
FEE60A; EE60
E60/16 0,441 67 17,708 × 10 110 249 27 300 243 C
−4
E65/27 0,273 57 5,095 4 × 10 147 537 78 900 530 C E65/27 FEE65,2
NOTE 1 Manufacturers can indicate more precise values in their catalogues than those given in Table 2.
NOTE 2 The above values have been calculated using the method given in IEC 60205.
a
The core size designation contains a combination of two numbers; the first one indicates the length A of the core and the second one its thickness C (see Table 1).
b
IEC 60205 shall be referred to for definition of A . The letters after the A values give the location of A : C is centre leg, L is outer leg, B is back wall.
min min min
c
Withdrawn publication.
4.3 Dimensional limits for coil formers
The dimensional limits for coil formers suitable for use with a pair of E-cores of size greater than E8/2 shall be as given in Table 3. See Figure 2 for
main dimensions of coil formers.

– 12 – IEC 63093-8:2018 © IEC 2018

l
e
s s
f
1 2
IEC
Figure 2 – Main dimensions of coil formers
k
c
Table 3 – Dimensional limits for coil formers
c e f k l s s
2 1 2
a
IEC 61246
Size mm mm mm mm mm mm mm Industrial references
references
Min. Max. Min. Min. Max. Min. Min.
E8/2 2,55 5,40 2,55 5,40 5,50 0,35 0,4 E8/2 FEE8
E8,3/4 3,95 5,90 2,15 5,90 5,60 0,35 0,4 FEE8,3; EE8
E8,8/2 2,17 4,87 2,17 4,87 3,86 0,35 0,4 E8,8/2 FEE9
E10/3 3,15 6,80 3,15 6,80 6,80 0,4 0,4 E10/3 FEE10
E10,2/5 5,05 7,40 2,75 7,40 7,90 0,4 0,5 FEE10,2; EE10/11
E13/4 3,90 8,70 3,90 8,70 8,80 0,5 0,5 E13/4 FEE12,7A; EF12,6
E13/6 6,45 9,80 3,05 9,80 8,80 0,4 0,5 EE13
E16/4,8 5,15 11,5 4,35 11,5 9,80 0,5 0,5 FEE16A; EE16
E16/5 4,90 11,1 4,90 11,1 11,2 0,5 0,5 E16/5 FEE16,1; EF16
E19/5 5,35 14,0 4,85 14,0 10,6 0,8 0,8 FEE19A; EE19
E19,3/4,8 5,98 13,85 5,98 13,85 11,0 0,8 0,8 EE-187; EE19/16
E20/6 6,10 13,9 6,10 13,9 13,8 0,5 0,6 E20/6 FEE20,1; EF20
E25/7 7,70 17,3 7,70 17,3 17,2 0,6 0,7 E25/7 FEE25,1; EF25
E25,4/6 6,80 18,4 6,80 18,4 12,2 0,8 0,8 FEE25,4A
E25,4/6,3 6,63 18,35 6,75 18,35 12,2 0,8 0,8 EE24/25; EE25/19
E30/11 11,2 19,3 11,2 19,3 15,6 0,8 0,8 FEE30A; EE30
E32/9 9,80 22,4 9,80 22,4 22,1 0,7 0,8 E32/9 FEE32,1; EF32
E33/13 13,2 22,9 10,2 22,9 17,7 0,8 0,8 FEE33A; EE33
E34,6/9 9,95 24,8 9,90 24,8 18,7 0,8 0,8 EE375; EE35/28B
E35/10 10,5 24,3 10,5 24,3 18,1 0,8 0,8 FEE35A; EE35
E40/11 11,3 27,3 11,3 27,3 19,7 0,8 0,8 FEE40A; EE40
E41/13 13,3 28,3 13,4 28,3 19,9 0,8 0,8 EE21; EE41/33C
E42/15 15,7 29,2 12,6 29,2 29,3 0,9 1,0 E42/15 FEE42A
E42/20 20,5 29,2 12,6 29,2 29,3 0,9 1,0 E42/20 FEE42B

– 14 – IEC 63093-8:2018 © IEC 2018

c e f k l s s
2 1 2
a
IEC 61246
Size mm mm mm mm mm mm mm Industrial references
references
Min. Max. Min. Min. Max. Min. Min.
E47/16 16,2 31,4 16,2 31,4 23,8 0,8 0,8 EE625; EE47/39
E50/15 15,3 34,0 15,3 34,0 24,7 0,8 0,8 EE50A; EE50
E55/21 21,7 37,1 17,6 37,1 36,7 1,0 1,0 E55/21 FEE55,2A
E55/25 25,7 37,1 17,6 37,1 36,7 1,0 1,0 E55/25 FEE55,2B
E60/16 16,3 43,3 16,3 43,3 27,1 0,8 0,8 FEE60A; EE60
E65/27 27,8 43,7 20,5 43,7 44,1 1,0 1,0 E65/27 FEE65,2
a
Withdrawn publication.
5 Limits of surface irregularities
5.1 General
Surface irregularities are defined in IEC 60424-1.
5.2 Examples of surface irregularities
Figure 3 shows different examples of surface irregularities of an E-core.
Chip
Cracks
Example of flash
Ragged edge
Pull-out
Pore
IEC
Crystallite
Figure 3 – Examples of surface irregularities
5.3 Chips and ragged edges
5.3.1 General
The minimum area is taken as 0,5 mm , to be distinguishable to the naked eye, and the
maximum allowable area is 30 mm .
Examples of allowable areas of chips are given in Annex C.
5.3.2 Chips and ragged edges on the mating surfaces
The areas of the chips located on the mating surfaces (chip 1 and chip 1' irregularities in
Figure 4) shall not exceed the following limits:
• the cumulative area of the chips shall be less than 6 % of the mating surface (whether
gapped or ungapped) of the centre leg;
• the total length of the ragged edges shall be less than 25 % of the perimeter of the
relevant surface.
5.3.3 Chips and ragged edges on the other surfaces
The allowable areas of chips on the other surfaces are doubled as compared to the limits for
the mating surface (see Figure 4).
The rule for ragged edges is the same as that for the mating surface.

– 16 – IEC 63093-8:2018 © IEC 2018
Mating surfaces
Chip 1'
Chip 2
Chip 1
Ragged
IEC
edges
Figure 4 – Chip location for E-cores
Area and length reference for visual inspection is given in Table 4.
Examples of allowable areas of chips are given in Annex C.

Table 4 – Area and length reference for visual inspection

– 18 – IEC 63093-8:2018 © IEC 2018
5.4 Cracks
The limits for cracks at various locations shown in Figure 5 are given in Table 5.
5.5 Flash
There shall be no flash extending from the core into the wire slot (see Figure 5).
5.6 Pull-outs
For E-cores the cumulative area of pull-outs of the core shall be less than 25 % of the total
area of a side surface (see Figure 5).
H
S3
S1''
S1
S1'
S7
S2''
S2
S3''
S2'
Example of flash
S5
Pull-out
S6'
S5'
S6
S3'
S5''
S4'''
S4''
W
S4
IEC
Figure 5 – Crack and pull-out locations for E-cores
T
Table 5 – Limits for cracks
Limits for Limits for
Type Location
single crack multiple cracks
Mating surface of centre
S1 and S1' < 25 % of dimension W < 50 % of dimension W
pole
S1" Corner of centre pole Not acceptable Not acceptable
S2 and S2' Mating surface of outer leg < 25 % of dimension H < 25 % of dimension H
S2" Side of outer leg < 25 % of dimension H < 25 % of dimension H
S3 and S3" Centre pole < 25 % of dimension W < 25 % of dimension W
S3' Bottom corner of centre < 25 % of dimension W < 25 % of dimension W
pole / back wall and outer
leg / back wall
S4 Bottom corner of outer leg / < 25 % of dimension T < 25 % of dimension T
back wall
S4" Back wall < 25 % of dimension T < 25 % of dimension T
S4''' Back wall < 50 % of dimension W < 100 % of dimension W
S5, S5' and S5" Outer leg < 50 % of dimension W < 100 % of dimension W
S6 Back surface < 50 % of dimension W < 100 % of dimension W
S6' Back surface < 25 % of dimension W < 25 % of dimension W
S7 Corner of outer leg Not acceptable Not acceptable

5.7 Crystallites
Figure 6 shows an example of crystallite location on E-cores:
• a single area of the crystallites located on any surface shall be less than 2 % of the
respective surface area;
• the cumulative area of the crystallites located on any surface shall be less than 4 % of the
respective surface area.
Crystallite
IEC
Figure 6 – Crystallite location for E-cores
5.8 Pores
Figure 7 shows an example of pore location on E-cores:
• the number of pores located on the same surface shall not exceed two; the total number of
pores located on all surfaces shall not exceed five;
• a hole with an area larger than 1 mm on any surface is not acceptable.

– 20 – IEC 63093-8:2018 © IEC 2018
Pore
IEC
Figure 7 – Pore location for E-cores

Annex A
(normative)
Derived standards
This document establishes values for the main dimensions of E-cores and coil formers and
enables full interchangeability to be achieved for components complying with its provisions.
Parties interested in making or using E-cores may find it desirable to lay down local standards
for everyday use that show the dimensions and tolerances in greater detail than those in
Clause 4, and correspond to the state of the art in that area. These are known as derived
standards. When doing so, care should be taken not to exclude any other type of E-core
meeting the requirements in this document that would also satisfy the performance
specification valid for a specific case.
It should be noted that even if a component complies with a derived standard and with the
requirements of Clause 4 of this document, therefore permitting core assemblies and coil
formers to be freely interchanged, its constituent parts may not necessarily be
interchangeable.
When requirements lead to the establishment of a national standard, the relevant national
standardization body is strongly requested to insert a note in such a national standard stating
that:
a) the national standard is in accordance with the dimensional requirements of IEC 63093-8,
but that more details are given in order to promote the practical use of the standard;
b) other solutions are possible within the framework of IEC 63093-8, and should not be
excluded if the resulting cores and coil formers are functionally interchangeable with those
in accordance with the national standard.

– 22 – IEC 63093-8:2018 © IEC 2018
Annex B
(normative)
Example of dimensions for gauges to check
the dimensions of E-cores complying with this document
B.1 General
The gauges shall be in accordance with Figure B.1 and Table B.1.
b
q (≥ c)
d
r
r
IEC
a) Gauge to check the dimensions of limbs and the height
s (≥ a)
b
IEC
b) Gauge to check the dimensions of width
Figure B.1 – Gauge dimensions
c
f
e
a
Table B.1 – Gauge dimensions
a b c d e f r
a
IEC 61246 Industrial
Size mm mm mm mm mm mm mm
references references
Min. Max. Min. Min. Max. Min. Max. Min. Max. Min. Max. Min.
E8/2 8,155 8,165 5,0 2,405 2,415 2,85 2,86 5,585 5,595 2,405 2,415 0,5 E8/2 FEE8
E8,3/4 8,605 8,615 5,0 3,805 3,815 2,90 2,91 6,085 6,095 2,405 2,415 0,5 FEE8,3; EE8
E8,8/2 9,405 9,415 5,0 2,025 2,035 2,03 2,04 5,055 5,065 2,025 2,035 0,5 E8,8/2 FEE9
E10/3 10,205 10,215 6,0 3,005 3,015 3,50 3,51 6,985 6,995 3,005 3,015 0,5 E10/3 FEE10
E10,2/5 10,505 10,515 6,0 4,905 4,915 4,05 4,06 7,585 7,595 2,605 2,615 0,5 FEE10,2; EE10/11
E13/4 13,105 13,115 7,0 3,705 3,715 4,50 4,51 8,885 8,895 3,705 3,715 0,5 E13/4 FEE12,7A; EF12,6
E13/6 13,205 13,215 7,0 6,305 6,315 4,50 4,51 9,985 9,995 2,905 2,915 0,5 EE13
E16/4,8 16,305 16,315 8,0 5,005 5,015 5,00 5,01 11,685 11,695 4,205 4,215 0,5 FEE16A; EE16
E16/5 16,705 16,715 9,0 4,705 4,715 5,70 5,71 11,285 11,295 4,705 4,715 0,5 E16/5 FEE16,1; EF16
E19/5 19,405 19,415 9,0 5,205 5,215 5,40 5,41 14,185 14,195 4,705 4,715 0,5 FEE19A; EE19
E19,3/4,8 19,615 19,625 9,0 4,885 4,895 5,59 5,60 14,035 14,045 4,835 4,845 0,5 EE-187; EE19/16
E20/6 20,805 20,815 11,0 5,905 5,915 7,00 7,01 14,085 14,095 5,905 5,915 0,7 E20/6 FEE20,1; EF20
E25/7 25,805 25,815 13,0 7,505 7,515 8,70 8,71 17,485 17,495 7,505 7,515 0,8 E25/7 FEE25,1; EF25
E25,4/6 25,905 25,915 11,0 6,655 6,665 6,20 6,21 18,585 18,595 6,655 6,665 0,8 FEE25,4A
E25,4/6,3 25,905 25,915 11,0 6,485 6,495 6,22 6,23 18,535 18,545 6,605 6,615 0,8 EE24/25;EE25/19
E30/11 30,605 30,615 14,0 11,005 11,015 7,90 7,91 19,485 19,495 11,005 11,015 0,8 FEE30A; EE30
E32/9 32,905 32,915 17,0 9,505 9,515 11,20 11,21 22,685 22,695 9,505 9,515 1,0 E32/9 FEE32,1; EF32
E33/13 33,905 33,915 15,0 13,005 13,015 9,00 9,01 23,085 23,095 10,005 10,015 1,0 FEE33A; EE33
E34,6/9 35,305 35,315 15,0 9,725 9,735 9,51 9,52 24,985 24,995 9,705 9,715 1,0 EE375; EE35/28B
E35/10 35,705 35,715 17,0 10,305 10,315 9,20 9,21 24,485 24,495 10,305 10,315 1,0 FEE35A; EE35
E40/11 41,875 41,885 18,0 11,005 11,015 10,00 10,01 27,485 27,495 11,005 11,015 1,0 FEE40A; EE40
E41/13 41,875 41,885 18,0 12,955 12,965 10,08 10,09 28,535 28,545 13,105 13,115 1,0 EE21; EE41/33C
E42/15 43,005 43,015 22,0 15,205 15,215 14,80 14,81 29,485 29,495 12,205 12,215 1,0 E42/15 FEE42A
E42/20 43,005 43,015 22,0 20,005 20,015 14,80 14,81 29,485 29,495 12,205 12,215 1,0 E42/20 FEE42B

– 24 – IEC 63093-8:2018 © IEC 2018

a b c d e f r
a
IEC 61246 Industrial
Size mm mm mm mm mm mm mm
references references
Min. Max. Min. Min. Max. Min. Max. Min. Max. Min. Max. Min.
E47/16 47,885 47,895 20,0 15,875 15,885 12,07 12,08 31,705 31,715 15,875 15,885 1,0 EE625; EE47/39
E50/15 51,005 51,015 22,0 15,005 15,015 12,50 12,51 34,285 34,295 15,005 15,015 1,0 EE50A; EE50
E55/21 56,205 56,215 28,0 21,005 21,015 18,50 18,51 37,485 37,495 17,205 17,215 1,0 E55/21 FEE55,2A
E55/25 56,205 56,215 28,0 25,005 25,015 18,50 18,51 37,485 37,495 17,205 17,215 1,0 E55/25 FEE55,2B
E60/16 61,105 61,115 23,0 16,005 16,015 13,70 13,71 43,685 43,695 16,005 16,015 1,0 FEE60A; EE60
E65/27 66,505 66,515 33,0 27,405 27,415 22,20 22,21 44,185 44,195 20,005 20,015 1,5 E65/27 FEE65,2
NOTE Manufactures can use more precise gauges or gauges for more precise core tolerances.
a
Withdrawn publication.
B.2 Procedure and requirements
To check the winding space, the gauge shall be fully inserted into the core without forcing; when fully inserted, the gauge shall meet the pole faces
of the outer legs.
Annex C
(informative)
Reference of allowable areas of chips
The reference of allowable areas of chips for a given core is summarized in Table C.1.
NOTE Table C.1 is taken from IEC 60424-3:2015, Table 4, and is included in Annex C for ease of reference.
Table C.1 – Allowable areas of chips for E-cores
Core size Mating surfaces Other surfaces
2 2
mm mm
E5,3/2 < 0,5 < 0,5
E6,3/2 < 0,5 < 0,5
E8/2 < 0,5 < 1
E8,3/4 < 0,5 < 1
E8,8/2 < 0,5 < 1
E10/3 < 1 < 1,5
E10,2/5 < 1 < 1,5
E13/4 < 1 < 2
E13/6 < 1 < 2
E16/4,8 < 1,5 < 3
E16/5 < 1,5 < 3
E19/5 < 1,5 < 3
E19,3/4,8 < 1,5 < 3
E20/6 < 2 < 4
E25/7 < 4 < 7
E25,4/6 < 2,5 < 5
E25,4/6,3 < 2,5 < 5
E30/11 < 7 < 14
E32/9 < 5 < 10
E33/13 < 7 < 14
E34,6/9 < 6 < 10
E35/10 < 6 < 12,5
E40/11 < 6 < 12,5
E41/13 < 10 < 20
E42/15 < 12,5 < 25
E42/20 < 15 < 30
E47/16 < 15 < 30
E50/15 < 12,5 < 25
E55/21 < 20 < 40
E55/25 < 25 < 50
E60/16 < 15 < 30
E65/27 < 30 < 60
– 26 – IEC 63093-8:2018 © IEC 2018
Bibliography
IEC 60424-3:2015, Ferrite cores – Guidelines on the limits of surface irregularities – Part 3:
ETD-cores, EER-cores, EC-cores and E-cores
IEC 61246, Magnetic oxide cores (E-cores) of rectangular cross-section and associated parts
– Dimensions
IEC 62317-8:2006, Ferrite cores – Dimensions – Part 8: E-cores

___________
___________
Withdrawn publication.
Withdrawn publication.
Withdrawn publication.
– 28 – IEC 63093-8:2018 © IEC 2018
SOMMAIRE
AVANT-PROPOS . 30
1 Domaine d'application . 32
2 Références normatives . 32
3 Termes et définitions . 32
4 Dimensions essentielles . 32
4.1 Généralités . 32
4.2 Dimensions des noyaux E . 33
4.2.1 Dimensions principales . 33
4.2.2 Valeurs des paramètres effectifs et de A . 35
min
4.3 Limites dimensionnelles des carcasses . 37
5 Limites des irrégularités de surface . 41
5.1 Généralités . 41
5.2 Exemples d'irrégularités de surface . 41
5.3 Eclats et bords ébréchés. 41
5.3.1 Généralités . 41
5.3.2 Eclats et bords ébréchés sur les surfaces de contact . 41
5.3.3 Eclats et bords ébréchés sur les autres surfaces . 41
5.4 Fissures . 44
5.5 Bavure . 44
5.6 Collages . 44
5.7 Cristallites . 45
5.8 Pores . 46
Annexe A (normative) Normes dérivées . 47
Annexe B (normative) Exemple de dimensions pour les calibres destinés à vérifier les
dimensions des noyaux E conformes au présent document . 48
B.1 Généralités . 48
B.2 Procédure et exigences . 50
Annexe C (informative) Référence des surfaces admissibles des éclats . 51
Bibliographie . 52

Figure 1 – Dimensions des noyaux E de section rectangulaire . 33
Figure 2 – Dimensions principales des carcasses . 38
Figure 3 – Exemples d'irrégularités de surface . 41
Figure 4 – Emplacement des éclats pour les noyaux E . 42
Figure 5 – Emplacements des fissures et des collage
...