IEC 60133:2000

INTERNATIONAL IEC
STANDARD
Fourth edition
2000-12
Dimensions of pot-cores made
of magnetic oxides and associated parts
Dimensions des circuits magnétiques en pots
en oxydes magnétiques et pièces associées

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INTERNATIONAL IEC
STANDARD
Fourth edition
2000-12
Dimensions of pot-cores made
of magnetic oxides and associated parts
Dimensions des circuits magnétiques en pots
en oxydes magnétiques et pièces associées

 IEC 2000  Copyright - all rights reserved
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International Electrotechnical Commission
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– 2 – 60133  IEC:2000(E)
CONTENTS
Page
FOREWORD . 3

Clause
1 Scope . 4

2 Normative reference. 4

3 Primary standards . 4

3.1 Dimensions of pot-cores. 4
3.1.1 Principal dimensions . 4
3.1.2 Grooves . 6
3.1.3 Effective parameter values . 7
3.2 Main dimensions for coil formers . 8
Annex A (informative) Pot-core design . 9
Annex B (informative) Derived standards. 10
Annex C (informative) Example of a standard for gauges to check the dimensions of pot-cores
meeting the IEC primary standard. 11
Figure 1 – Principal dimensions of pot-cores without slots. 4
Figure 2 – Principal dimensions of pot-cores with slots. 5
Figure 3 – Main dimensions for coil formers . 8
Figure C.1 – Dimensions of gauge A. 11
Figure C.2 – Dimensions of gauges B and C . 12
Table 1 – Principal dimensions of pot-cores . 5
Table 2 – Limits for C and G . 6
Table 3 – Minimum groove depth . 6

Table 4 – Effective parameter values pot-cores with a centre hole. 7
Table 5 – Effective parameter values pot-cores without a centre hole . 7
Table 6 – Main dimensions for coil formers . 8
Table A.1 – Ratio of diameter to height . 9
Table C.1 – Dimensions of gauge A . 11
Table C.2 – Dimensions of gauges B and C . 12

60133 © IEC:2000(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

___________
DIMENSIONS OF POT-CORES MADE OF MAGNETIC OXIDES

AND ASSOCIATED PARTS
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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. The 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 the 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 National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60133 has been prepared by technical committee 51: Magnetic
components and ferrite materials.
This edition cancels and replaces the third edition published in 1985, of which it constitutes a
technical revision.
The text of this standard is based on the following documents:
FDIS Report on voting
51/570/FDIS 51/580/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 3.
The committee has decided that the contents of this publication will remain unchanged until
2004. At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
A bilingual version of this standard may be issued at a later date.

– 4 – 60133  IEC:2000(E)
DIMENSIONS OF POT-CORES MADE OF MAGNETIC OXIDES

AND ASSOCIATED PARTS
1 Scope
This standard specifies the dimensions that are of importance for mechanical interchangeability

for a preferred range of pot-cores made of magnetic oxides, and the dimensional limits for coil

formers to be used with them. The general considerations upon which the design of this range
of cores is based are given in annex A.
2 Normative reference
The following normative documents contain provisions which, through reference in this text,
constitute provisions of this International Standard. For dated references, subsequent
amendments to, or revisions of, any of these publications do not apply. However, parties to
agreements based on this International Standard are encouraged to investigate the possibility
of applying the most recent editions of the normative documents indicated below. For undated
references, the latest edition of the normative document referred to applies. Members of IEC
and ISO maintain registers of currently valid International Standards.
IEC 60205, Calculation of effective parameters of magnetic piece parts
3 Primary standards
Compliance with the following requirements ensures mechanical interchangeability of complete
assemblies and coil formers.
3.1 Dimensions of pot-cores
3.1.1 Principal dimensions
The principal dimensions of pot-cores shall be as given in table 1.
2B
X
2D
r
X
Section X- X
IEC  2587/2000
Figure 1 – Principal dimensions of pot-cores without slots
G
H
F
E
A
60133 © IEC:2000(E) – 5 –
2B
X
C 2D
r1
X
Section X- X
IEC  2588/2000
Figure 2 – Principal dimensions of pot-cores with slots
Table 1 – Principal dimensions of pot-cores
Dimensions in millimetres
1)
Size AE F H 2B 2D r Figures
Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Max.
P3,3/2,6 3,18 3,30 2,50 2,60 1,30 1,40 – – 2,50 2,60 1,70 1,90 0,20  1
P4,6/3,1 4,40 4,60 3,50 3,65 1,90 2,00 – – 3,00 3,10 2,10 2,30 0,20  1
P5,8/3,3 5,65 5,80 4,50 4,60 2,40 2,50 0,95 1,05 3,20 3,30 2,20 2,40 0,20  1
P7,4/4,0 7,15 7,35 5,80 5,95 2,90 3,00 1,05 1,15 4,10 4,20 2,80 3,00 0,20  1
P9/5 9 9,3 7,5 7,75 3,7 3,9 2 2,2 5,1 5,4 3,6 3,9 0,25  2
P11/7 10,9 11,3 9 9,4 4,5 4,7 2 2,2 6,3 6,6 4,4 4,7 0,25  2
P14/8 13,8 14,3 11,6 12 5,8 6 3 3,2 8,2 8,5 5,6 6 0,25  2
P18/11 17,6 18,4 14,9 15,4 7,3 7,6 3 3,2 10,4 10,7 7,2 7,6 0,25  2
P22/13 21,2 22 17,9 18,5 9,1 9,4 4,4 4,7 13,2 13,6 9,2 9,6 0,35  2
P26/16 25 26 21,2 22 11,1 11,5 5,4 5,7 15,9 16,3 11 11,4 0,35  2
13,4 0,35  2
P30/19 29,5 30,5 25 25,8 13,1 13,5 5,4 5,7 18,6 19 13
P36/22 35 36,2 29,9 30,9 15,6 16,2 5,4 5,7 21,4 22 14,6 15 0,35  2
NOTE 1 P3,3/2,6 and P4,6/3,1 cores are without the centre hole shown in figure 1.

NOTE 2 P9/5 and P11/7 cores are without the centre hole shown in figure 2.
NOTE 3 Sharp inner corners of pot-cores are preferable but in practice some rounding may occur, provided that radius r is
1)
not exceeded .
NOTE 4 The dimensions of the cores may be checked by means of gauges. An example of a possible standard for these
gauges is given in annex C.
NOTE 5 In order to facilitate production, it may be necessary to use gauges having dimensions differing from those given in
annex C, although no relaxation of the requirements for the dimensions of the cores given in 3.1 is thereby permitted.
G
H
F
E
A
– 6 – 60133  IEC:2000(E)
Table 2 – Limits for C and G
Dimensions in millimetres
Size Cores with two slots
CG
Min. Max. Min. Max.
P3,3/2,6 – – 0,8 1,3
P4,6/3,1 – – 1,1 1,7
P5,8/3,3 – – 1,4 2,0
P7,4/4,0 – – 1,6 2,2
P9/5 6,0 7,5 1,6 2,4
P11/7 6,5 8,0 1,8 2,6
P14/8 8,7 10,0 2,3 4,1
P18/11 11,3 14,0 2,7 4,4
P22/13 13,3 16,5 3,0 4,4
P26/16 17,0 20,0 3,0 4,4
P30/19 20,0 23,0 3,5 5,3
P36/22 24,0 27,2 4,0 5,6
NOTE 1 The shape of the slots is not defined, but the width G is indicated in the table.
NOTE 2 It is recommended that any tightening of the tolerance on dimension C should be towards
the minimum value and on dimension G towards the maximum value.
3.1.2 Grooves
When grooves are provided corresponding to the slots, their minimum depth shall be as given
in table 3.
Table 3 – Minimum groove depth
Dimensions in millimetres
Size Minimum groove depth
P14/8 0,2
P18/11 0,3
P22/13 0,4
P26/16 0,5
P30/19 0,6
P36/22 0,6
60133 © IEC:2000(E) – 7 –
3.1.3 Effective parameter values

The effective parameter values for pot-cores whose dimensions comply with 3.1.1 shall be as

given in tables 4 and 5 (for the definitions of these parameters, and their calculation, see

IEC 60205).
Table 4 – Effective parameter values pot-cores with a centre hole

C C A l V A
Size 1 2 e e e min
–1 –3 –3 2 3 2
mm 10 mm mm mm mm mm
P5,8/3,3 1,6326 345,47 4,73 7,72 36,5 3,66
P7,4/4,0 1,3588 186,79 7,27 9,88 71,9 5,79
P9/5 1,2032 118,12 10,2 12,3 125 7,88
P11/7 0,933 53 56,727 16,5 15,4 253 13,2
P14/8 0,757 42 29,521 25,7 19,4 499 19,8
P18/11 0,573 83 12,863 44,6 25,6 1 140 36,0
P22/13 0,480 78 7,4185 64,8 31,2 2 020 50,9
P26/16 0,389 23 4,0605 95,9 37,3 3 580 76,1
P30/19 0,323 43 2,3321 139 44,9 6 220 1
...