IEC 60205:2016

IEC 60205 ®
Edition 4.0 2016-11
INTERNATIONAL
STANDARD
Calculation of the effective parameters of magnetic piece parts
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IEC 60205 ®
Edition 4.0 2016-11
INTERNATIONAL
STANDARD
Calculation of the effective parameters of magnetic piece parts

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.100.10 ISBN 978-2-8322-3775-5

– 2 – IEC 60205:2016 © IEC 2016
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions. 7
4 Basic rules applicable to this standard . 7
5 Formulae for the various types of cores . 8
5.1 Ring cores . 8
5.1.1 Ring cores in general . 8
5.1.2 For ring cores of rectangular cross-section with sharp corners . 9
5.1.3 For ring cores of rectangular cross-section with an appreciable average
rounding radius r . 9
5.1.4 For ring cores of rectangular cross-section with appreciable chamfer c . 9
5.1.5 For ring cores of trapezoidal cross-section with sharp corners . 9
5.1.6 For ring cores of trapezoidal cross-section with an appreciable average
rounding radius r . 9
5.1.7 For ring cores of cross-section with circular arc frontal sides . 9
5.2 Pair of U-cores of rectangular section . 10
5.3 Pair of U-cores of rounded section . 10
5.4 Pair of E-cores of rectangular section . 11
5.5 Pair of ETD/EER-cores . 12
5.6 Pair of pot-cores . 14
5.7 Pair of RM-cores . 16
5.8 Pair of EP-cores . 20
5.9 Pair of PM-cores . 21
5.10 Pair of EL-cores . 23
5.11 Pair of ER-cores (low profile) . 25
5.12 Pair of PQ-cores . 28
5.13 Pair of EFD-cores. 31
5.14 Pair of E planar-cores . 33
5.15 Pair of EC-cores . 34
Bibliography . 37

Figure 1 – Ring cores . 8
Figure 2 – Pair of U-cores of the rectangular section . 10
Figure 3 – Pair of U-cores of rounded section . 11
Figure 4 – Pair of E-cores of rectangular section . 12
Figure 5 – Pair of ETD/EER-cores . 13
Figure 6 – Pair of pot-cores . 14
Figure 7 – Pair of RM-cores . 18
Figure 8 – Pair of EP-cores . 20
Figure 9 – Pair of PM-cores . 22
Figure 10 – Pair of EL-cores . 23

Figure 11 – PLT(plate)-cores . 24
Figure 12 – Pair of ER-cores (low profile) . 26
Figure 13 – PLT(plate)-cores . 26
Figure 14 – Pair of PQ-cores . 28
Figure 15 – PQ-cores . 29
Figure 16 – PLT(plate)-cores . 29
Figure 17 – Pair of EFD-cores . 31
Figure 18 – Pair of E planar-cores . 33
Figure 19 – PLT(plate)-cores . 33
Figure 20 – Pair of EC-cores . 35

– 4 – IEC 60205:2016 © IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CALCULATION OF THE EFFECTIVE PARAMETERS
OF MAGNETIC PIECE PARTS
FOREWORD
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International Standard IEC 60205 has been prepared by IEC technical committee 51: Magnetic
components, ferrite and and magnetic powder materials.
This fourth edition cancels and replaces the third edition published in 2006 and
Amendment 1:2009. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) addition, in 5.1, of the drawing of a core of rectangular cross-section with chamfer;
b) addition, in 5.1.3, of the equation of a core of rectangular cross-section with chamfer;
c) equations in 5.1.4, 5.6, 5.7, 5.8, 5.9, 5.11, 5.12, 5.14 are amended or replaced;
d) drawings RM6-S and RM6-R in 5.7 are amended;
e) addition of EC-cores, see 5.15.

The text of this standard is based on the following documents:
FDIS Report on voting
51/1149/FDIS 51/1156/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
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,
...