IEC TR 63090:2017

IEC TR 63090 ®
Edition 1.0 2017-05
TECHNICAL
REPORT
colour
inside
Dimensional tolerances of ferrite cores
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IEC TR 63090 ®
Edition 1.0 2017-05
TECHNICAL
REPORT
colour
inside
Dimensional tolerances of ferrite cores

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.100.10 ISBN 978-2-8322-4349-7

－ 2 － IEC TR 63090:2017 © IEC 2017
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Summary of dimensional tolerances of ferrite cores . 7
4.1 General . 7
4.2 Dimensional tolerances of E-cores . 7
4.3 Dimensional tolerances of ring cores . 9
4.4 Dimensional tolerances of ETD/EER-cores . 11
4.5 Dimensional tolerances of planar ER-cores . 13
5 Conclusion . 15
Annex A (informative) Data of dimensional tolerances . 16
A.1 E-core . 16
A.2 Ring core . 34
A.3 ETD/EER-core . 43
A.4 Planar ER-core . 49
Bibliography . 55

Figure 1 – Cause-and-effect diagram of variations in dimension . 6
Figure 2 – E-core . 7
Figure 3 – Dimensional tolerances of each part of E-cores . 9
Figure 4 – Ring core . 10
Figure 5 – Dimensional tolerances of each part of ring cores . 11
Figure 6 – ETD/EER-core . 11
Figure 7 – Dimensional tolerances of each part of ETD/EER-cores . 13
Figure 8 – Planar ER-core . 14
Figure 9 – Dimensional tolerances of each part of planar ER-cores . 15

Table 1 – IEC standards of ferrite core dimensions . 5
Table 2 – Dimensional tolerances recommended for a new design of E-cores . 8
Table 3 – Dimensional tolerances recommended for a new design of ring cores . 10
Table 4 – Dimensional tolerances recommended for a new design of ETD/EER-cores . 12
Table 5 – Dimensional tolerances recommended for a new design of planar ER-cores . 14
Table A.1 – Dimensional tolerances of each part (E-core) . 16
Table A.2 – Dimensional tolerances of each part (Ring-core) . 34
Table A.3 – Dimensional tolerances of each part (ETD/EER-core) . 43
Table A.4 – Dimensional tolerances of each part (Planar ER-core) . 49

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DIMENSIONAL TOLERANCES OF FERRITE CORES

FOREWORD
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IEC TR 63090, which is a Technical Report, has been prepared by IEC technical committee
51: Magnetic components, ferrite and magnetic powder materials.
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
51/1166/DTR 51/1186/RVDTR
Full information on the voting for the approval of this technical report 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.

－ 4 － IEC TR 63090:2017 © IEC 2017
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INTRODUCTION
This document shows the dimensional tolerances of ferrite cores that are generally used by
ferrite core suppliers. As a reference, this is useful for ferrite core suppliers and users when
they design ferrite cores and/or the components which use the ferrite cores.
IEC has published international standards regarding ferrite core dimensions and their
tolerances, as listed in the Table 1, and core sizes in each core shape were chosen from
industrial standards from Europe, Japan and USA. However, there are some cases that lack
unity in the dimensional tolerances even if ferrite core dimensions are close.
Because many new sizes are still designed for the E, ETD/EER, planar ER and ring core, this
document gives information about the dimensional tolerances for reference dimensions of
each core shape.
Table 1 – IEC standards of ferrite core dimensions
IEC standard Current standard
IEC 62317-1, Ferrite cores – Dimensions – Part 1: General specification ///
IEC 62317-2, Ferrite cores – Dimensions – Part 2: Pot-cores for use in ///
telecommunications, power supply, and filter applications
IEC 62317-3, Ferrite cores – Dimensions – Part 3: Half-pot cores (future standard) IEC 62323
IEC 62317-4, Ferrite cores – Dimensions – Part 4: RM-cores and associated parts ///
IEC 62317-5, Ferrite cores – Dimensions – Part 5: EP-cores and associated parts for use ///
in inductors and transformers
IEC 62317-6, Ferrite cores – Dimensions – Part 6: ETD-cores for use in power supplies ///
IEC 62317-7, Ferrite cores – Dimensions – Part 7: EER-cores ///
IEC 62317-8, Ferrite cores – Dimensions – Part 8: E-cores ///
IEC 62317-9, Ferrite cores – Dimensions – Part 9: Planar cores ///
IEC 62317-10, Ferrite cores – Dimensions – Part 10: PM cores (future standard) IEC 61247
IEC 62317-11, Ferrite cores – Dimensions – Part 11: EC-cores for use in power supply ///
applications
IEC 62317-12, Ferrite cores – Dimensions – Part 12: Ring cores ///
IEC 62317-13, Ferrite cores – Dim
...