IEC 62317-6:2015

IEC 62317-6 ®
Edition 1.0 2015-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Ferrite cores – Dimensions –
Part 6: ETD-cores for use in power supplies

Noyaux ferrites – Dimensions –
Partie 6: Noyaux ETD destinés à être utilisés dans des alimentations

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IEC 62317-6 ®
Edition 1.0 2015-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Ferrite cores – Dimensions –
Part 6: ETD-cores for use in power supplies

Noyaux ferrites – Dimensions –

Partie 6: Noyaux ETD destinés à être utilisés dans des alimentations

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.100.10 ISBN 978-2-8322-3030-5

– 2 – IEC 62317-6:2015 © IEC 2015

CONTENTS
FOREWORD . 3

1 Scope . 5

2 Normative references . 5

3 Primary standards . 5

3.1 General . 5

3.2 Dimensions of ETD-cores . 5

3.2.1 Principal dimensions . 5

3.2.2 Effective parameter and A values . 6
min
3.3 Dimensional limits for coil formers. 7
3.4 Pin locations and base outlines . 8
3.5 Pin diameter . 11
4 Marking . 11
5 Mounting . 11
Annex A (normative) Derived standards . 12
Annex B (normative) Example of a standard for gauges to check the dimensions of
ETD-cores meeting this primary standard . 14
B.1 General . 14
B.2 Procedure and requirements . 14
Bibliography . 15

Figure 1 – Dimensions of ETD-cores . 6
Figure 2 – Essential dimensions of coil formers . 7
Figure 3 – Pin locations and base outlines viewed from the upper-side of the board
(see 3.4) (1 of 2) . 9
Figure A.1 – Main dimensions of coil formers . 13
Figure B.1 – Gauge dimensions . 14

Table 1 – Dimensions of ETD-cores . 6
Table 2 – Effective parameter and A values . 7
min
Table 3 – Essential dimensions of coil formers. 8
Table A.1 – Main dimensions of coil formers . 13
Table B.1 – Gauge dimensions . 14

INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
FERRITE CORES – DIMENSIONS –
Part 6: ETD-cores for use in power supplies

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62317-6 has been prepared by IEC technical committee 51:

Magnetic components and ferrite materials.
This first edition cancels and replaces the second edition of IEC 61185 published in 2005.
This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Changed dimension A of ETD 54 core.

– 4 – IEC 62317-6:2015 © IEC 2015

The text of this standard is based on the following documents:

FDIS Report on voting
51/1105/FDIS 51/1120/RVD
Full information on the voting for the approval of this standard can be found in the report on

voting indicated in the above table.

This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all parts in the IEC 62317 series, published under the general title Ferrite cores –
Dimensions, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
FERRITE CORES – DIMENSIONS –
Part 6: ETD-cores for use in power supplies

1 Scope
This part of IEC 62317 specifies the dimensions that are of importance for mechanical

interchangeability for ETD-cores made of ferrite, the essential dimensions of coil formers to
be used with them, and the effective parameter values to be used in calculations involving
them.
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, which also
contains an example of a derived standard for coil formers.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
Void.
3 Primary standards
3.1 General
Compliance with the following requirements ensures the mechanical interchangeability of
complete assemblies and coil formers.
3.2 Dimensions of ETD-cores
3.2.1 Principal dimensions
The principal dimensions of ETD-cores shall be as given in Figure 1 and Table 1.

The dimensions of the cores may be checked by means of gauges. By way of example, a
possible standard for these gauges is given in Annex B. In order to facilitate production it may
be necessary to use gauges having 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
permitted.
– 6 – IEC 62317-6:2015 © IEC 2015

C
B
D
IEC
Figure 1 – Dimensions of ETD-cores
Table 1 – Dimensions of ETD-cores
A B C D E F
Size mm mm mm mm mm mm
Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max.
ETD 19 19,1 20,1 13,5 13,8 7,2 7,6 9,2 9,6 14,4 15,4 7,2 7,6
ETD 24 23,8 25,0 14,3 14,6 8,2 8,8 9,9 10,3 18,0 19,2 8,2 8,8
ETD 29 29,0 30,6 15,6 16,0 9,2 9,8 10,7 11,3 22,0 23,4 9,2 9,8
ETD 34 33,4 35,0 17,1 17,5 10,5 11,1 11,8 12,4 25,6 27,0 10,5 11,1
ETD 39 38,2 40,0 19,6 20,0 12,2 12,8 14,2 15,0 29,3 30,9 12,2 12,8
ETD 44 43,0 45,0 22,1 22,5 14,4 15,2 16,1 16,9 32,5 34,1 14,4 15,2
ETD 49 47,6 49,8 24,5 24,9 15,9 16,7 17,7 18,5 36,1 37,9 15,9 16,7
ETD 54 53,2 55,8 27,4 27,8 18,5 19,3 19,8 20,6 40,1 42,3 18,5 19,3
ETD 59 58,4 61,2 30,8 31,2 21,2 22,1 22,0 22,9 43,6 45,8 21,2 22,1

3.2.2 Effective parameter and A values
min
The effective parameter values of a pair of cores whose dimensions comply with 3.2.1 shall
be as given in Table 2.
A is specified in IEC 60205:2009, 2.2.
min
F
E
A
Table 2 – Effective parameter and A values
min
C C L A V A
1 2 e e e min
Size
–1 –3 2 3 2
mm mm mm mm mm mm
–3
ETD 19 1,253 9 55,3 44,1 2 440 39,5
28,412 × 10
–3
ETD 24 1,053 7 17,811 × 10 62,3 59,2 3 690 55,0

–3
ETD 29 0,927 07 70,8 76,4 5 410 70,9
12,139 × 10
–3
ETD 34 0,814 49 79,1 97,1 7 680 91,6
8,387 9 × 10
–3
ETD 39 0,742 00 5,940 1 × 10 92,7 125 11 600 123

–3
ETD 44 0,599 18 3,462 8 × 10 104 173 17 900 172
–3
ETD 49 0,542 45 115 211 24 200 209
2,569 2 × 10
–3
ETD 54 0,455 01 127 280 35 700 280
1,625 1 × 10
–3
ETD 59 0,382 24 1,038 9 × 10 141 368 51 700 366
NOTE 1 The manufacturers may indicate in their catalogues more precise values than those given in Table 2.
NOTE 2 The above values have been calculated using the method given in IEC 60205:2009, 3.5.

3.3 Dimensional limits for coil formers
The essential dimensions of coil formers suitable for use with a pair of ETD-cores shall be as
given in Figure 2 and Table 3.
d
d
IEC
Figure 2 – Essential dimensions of coil formers
f
f
e
– 8 – IEC 62317-6:2015 © IEC 2015

Table 3 – Essential dimensions of coil formers

e f f d d
1 2 1
Size mm mm mm mm mm
Max. Max. Min. Max. Min.
ETD 19 14,1 9,8 7,8 18,2 15,9

ETD 24 17,6 11,0 9,0 19,6 17,1

ETD 29 21,6 12,0 10,0 21,2 18,7

ETD 34 25,2 13,6 11,3 23,4 20,9

ETD 39 28,8 15,3 13,0 28,2 25,7
ETD 44 32,0 17,7 15,4 32,0 29,5
ETD 49 35,5 19,5 17,0 35,2 32,2
ETD 54 39,5 22,1 19,6 39,3 36,3
ETD 59 43,0 24,9 22,4 43,7 40,7

3.4 Pin locations and base outlines
These shall be as shown in Figure 3, in which the base is viewed in the mounting direction, i.e.
from the upper side of the printed wiring board.
NOTE The module, designated as m, as shown in the grid plan, may be 2,50 mm or 2,54 mm.

4 × (2m)
5 × (2m)
ETD 19
ETD 24
6 × (2m)
m
Earth
6 × (2m)
points
ETD 29 ETD 34
8 × (2m)
m
7 × (2m)
m
Earth Earth
points points
ETD 39 ETD 44
IEC
Figure 3 – Pin locations and base outlines
viewed from the upper-side of the board (see 3.4) (1 of 2)
6 × (2m)
7 × m
5 × (2m)
1,6
1,6
2m
1,6
5 × (2m)
9 × m
7 × (2m)
1,6
1,6
2m
1,6
2m
– 10 – IEC 62317-6:2015 © IEC 2015

9 × (2m)
m
Earth
points
ETD 49
11 × (2m)
ETD 54
12 × (2m)
ETD 59
IEC
Figure 3 (2 of 2)
9 × (2m)
10 × (2m)
8 × (2m)
1,6
2m
1,6
3,2
1,6
3,2
3.5 Pin diameter
Coil former terminations (pins) shall be accepted by a gauge having 1,2 mm holes on a true

position.
4 Marking
Where a coil former is fitted with termination pins conforming to a 2,50 mm module, it shall be

clearly and indelibly marked with the letter m, in such a position that it can readily be seen in

the completed component.
5 Mounting
According to their sizes and respective weights, it is recommended that two of the largest
cores (ETD 54 and ETD 59) be fixed on the printed board by means of screws located at two
opposite sides of their coil formers.
Concerning smaller sizes such as ETD 19 and ETD 24, no mounting assemblies are defined.
It is recommended that the two cores be fixed by glue or adhesive tape.

– 12 – IEC 62317-6:2015 © IEC 2015

Annex A
(normative)
Derived standards
Clauses 1 to 4 of this primary standard establish the values for the principal dimensions of

core assemblies and wound coil formers and enable full interchangeability for components
complying with this primary standard to be achieved.

Parties interested in making or using ETD-cores may find it desirable to lay down local
standards for everyday use, which show the dimensions and tolerances in greater detail than
Clause 3 and which correspond to the state of the art in that area. These specifications are
known as “derived standards”. When doing so, care should be taken not to exclude any other
type of ETD-core meeting this primary standard 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 3 of this primary standard, 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) it is in accordance with the dimensional requirement of this present primary standard but
that more details are given in order to promote its practical use;
b) other solutions are possible within the framework of this primary standard and should not
be excluded if the resulting core and formers are functionally interchangeable with those
of the national standard.
By way of example, a possible derived standard for coil formers is given in Figure A.1.
An example of a standard for the main dimensions of coil formers for ETD-cores meeting this
primary standard is given in Figure A.1 and Tab
...