IEC 63093-13:2019

IEC 63093-13 ®
Edition 1.0 2019-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Ferrite cores – Guidelines on dimensions and the limits of surface irregularities –
Part 13: PQ-cores
Noyaux ferrites – Lignes directrices relatives aux dimensions et aux limites des
irrégularités de surface –
Partie 13: Noyaux PQ
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IEC 63093-13 ®
Edition 1.0 2019-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Ferrite cores – Guidelines on dimensions and the limits of surface irregularities –

Part 13: PQ-cores
Noyaux ferrites – Lignes directrices relatives aux dimensions et aux limites des

irrégularités de surface –
Partie 13: Noyaux PQ
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.100.10 ISBN 978-2-8322-6506-2

– 2 – IEC 63093-13:2019 © IEC 2019
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Primary dimensions . 7
4.1 General . 7
4.2 Dimensions of PQ-cores . 7
4.2.1 Principal dimensions . 7
4.2.2 Effective parameter and A values . 7
min
4.3 Dimensional limits for coil formers. 7
4.4 Pin locations and base outlines . 7
4.5 Pin diameter . 7
5 Mounting . 12
6 Definitions and limits of surface irregularities . 13
6.1 General . 13
6.2 Examples of surface irregularities . 13
6.3 Chips and ragged edges . 13
6.3.1 General . 13
6.3.2 Chips and ragged edges located on the mating surface . 13
6.3.3 Chips and ragged edges located on the other surfaces . 14
6.4 Cracks . 16
6.5 Pull-out . 17
6.6 Crystallites . 17
6.7 Flash . 17
6.8 Pores . 18
Annex A (informative) PQ-cores design . 19
Annex B (informative) Examples of allowable areas of chips . 20
Annex C (normative) Example of a gauge to check the dimensions of PQ-cores
meeting the primary dimensions . 21
C.1 General . 21
C.2 Procedure and requirements . 22

Figure 1 – Dimensions of PQ-cores . 7
Figure 2 – Dimensions of low-profile PQI-cores . 9
Figure 3 – Main dimensions of coil formers for PQ-cores . 11
Figure 4 – Pin locations and base outlines viewed from the upper side of the board . 12
Figure 5 – Examples of surface irregularities . 13
Figure 6 – Chips and ragged edges locations. 14
Figure 7 – Cracks locations. 16
Figure 8 – Pull-out location . 17
Figure 9 – Crystallite location. 17
Figure 10 – Flash location . 18
Figure 11 – Pore location . 18
Figure C.1 – Gauge dimensions . 21

Table 1 – Dimensions of PQ-cores . 8
Table 2 – Dimensions of low-profile PQI-cores . 9
Table 3 – Effective parameter and A values for PQ-cores . 10
min
Table 4 – Effective parameter and A values for low-profile PQI-cores . 10
min
Table 5 – Dimensional limits for coil formers for PQ-cores . 11
Table 6 – Area and length reference of irregularities for visual inspection . 15
Table 7 – Limits for cracks . 16
Table B.1 – Allowable areas of chips in mm . 20
Table C.1 – Gauge dimensions . 21

– 4 – IEC 63093-13:2019 © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FERRITE CORES – GUIDELINES ON DIMENSIONS
AND THE LIMITS OF SURFACE IRREGULARITIES –

Part 13: PQ-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
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6) All users should ensure that they have the latest edition of this publication.
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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 63093-13 has been prepared by IEC technical committee 51:
Magnetic components, ferrite and magnetic powder materials.
This first edition cancels and replaces the second edition of IEC 62317-13 published in 2015
and the first edition of IEC 60424-8 published in 2015. This edition constitutes a technical
revision.
This edition includes the following significant technical changes with respect to the previous
editions of
IEC 62317-13 and IEC 60424-8:
a) IEC 63093-13 integrates IEC 62317-13 and IEC 60424-8;
b) IEC 60424-8:2015, Table 1, has been included in Annex B as Table B.1.

The text of this International Standard is based on the following documents:
FDIS Report on voting
51/1262/FDIS 51/1270/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.
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 63093-13:2019 © IEC 2019
FERRITE CORES – GUIDELINES ON DIMENSIONS
AND THE LIMITS OF SURFACE IRREGULARITIES –

Part 13: PQ-cores
1 Scope
This part of IEC 63093 specifies the dimensions that are of importance for mechanical
interchangeability for a preferred range of PQ-cores and low-profile PQI-cores made of ferrite,
and the locations of their terminal pins on a 2,54 mm printed wiring grid in relation to the base
outlines of the cores. It also gives guidance on allowable limits of surface irregularities
applicable to PQ-cores in accordance with the relevant generic specification.
The selection of core sizes for this document is based on the philosophy of including those
sizes which are industrial standards, either by inclusion in a national standard, or by
broad-based use in industry.
This document is a specification useful in the negotiations between ferrite core manufacturers
and customers about surface irregularities.
The general considerations that the design of this range of cores is based upon are given 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 purposes 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 wound coil formers.
4.2 Dimensions of PQ-cores
4.2.1 Principal dimensions
The principal dimensions of PQ-cores shall be as given in Table 1 and those of the low-profile
PQI-cores shall be as given in Table 2. See also Figure 1 and Figure 2. 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 C, although no relaxation of the requirements for the dimensions of
the cores given in Table 1 and in Table 2 is permitted.
4.2.2 Effective parameter and A values
min
The effective parameter values for cores having the dimensions given in 4.2 are as shown in
Table 3 and Table 4.
The definitions of effective parameters and their calculations shall be as given in IEC 60205.
4.3 Dimensional limits for coil formers
The main dimensions of coil formers suitable for use with a pair of PQ-cores shall be as given
in Table 5. See also Figure 3.
4.4 Pin locations and base outlines
These shall be as shown in Figure 4.
4.5 Pin diameter
Coil former terminations (pins) shall be accepted by a gauge having 1,2 mm holes on a true
position.
Figure 1 – Dimensions of PQ-cores

– 8 – IEC 63093-13:2019 © IEC 2019
Table 1 – Dimensions of PQ-cores
A B C D E F G J L
Size
mm mm mm mm mm mm mm mm mm
Min. 16,10 5,70 10,90 3,20 14,10 6,80 8,80
PQ 16/11,6 Nom.    3,1 8,5
Max. 16,70 5,90 11,50 3,50 14,70 7,20 10,40
Min. 20,10 8,00 13,60 5,00 17,60 8,60 12,00
PQ 20/16 Nom.    4,80 10,50
Max. 20,90 8,20 14,40 5,30 18,40 9,00 13,00
Min. 20,10 10,00 13,60 7,00 17,60 8,60 12,00
PQ 20/20 Nom.    4,80 10,50
Max. 20,90 10,20 14,40 7,30 18,40 9,00 13,00
Min. 26,05 9,95 18,55 5,60 22,05 11,80 15,50
PQ 26/20 Nom.    7,30 13,90
Max. 26,95 10,20 19,45 5,90 22,95 12,20 16,50
Min. 26,05 12,25 18,55 7,90 22,05 11,80 15,50
PQ 26/25 Nom    7,30 13,90
Max 26,95 12,50 19,45 8,20 22,95 12,20 16,50
Min. 31,50 10,15 21,50 5,60 27,00 13,20 19,00
PQ 32/20 Nom.    6,20 15,10
Max. 32,50 10,40 22,50 5,90 28,00 13,70 20,00
Min. 31,50 15,05 21,50 10,50 27,00 13,20 19,00
PQ 32/30 Nom.    6,20 15,10
Max. 32,50 15,30 22,50 10,80 28,00 13,70 20,00
Min. 34,50 17,25 25,50 12,35 31,50 14,10 23,50
PQ 35/35 Nom.    7,30 16,40
Max. 35,70 17,50 26,50 12,65 32,50 14,60 24,50
Min. 39,70 19,75 27,40 14,60 36,40 14,60 28,00
PQ 40/40 Nom.    7,75 16,80
Max. 41,30 20,00 28,60 14,90 37,60 15,20 29,00
Min. 49,00 24,85 31,50 17,90 43,30 19,65 31,50
PQ 50/50 Nom.    10,00 22,00
Max. 51,00 25,10 32,50 18,20 44,70 20,35 32,50
Min. 63,70 26,80 39,20 17,75 52,00 25,55 39,20
PQ 65/54 Nom.    12,00 27,50
Max. 66,30 27,20 40,80 18,25 54,00 26,45 40,80
Min. 77,00 19,45 41,20 12,60 69,10 25,00 60,10
PQ 78/39 Nom.    13,60 27,60
Max. 80,00 19,95 42,80 13,20 71,90 26,00 62,50
Min. 105,00 43,10 68,50 27,50 93,70 40,20 72,50
PQ 107/87 Nom.    22,80 43,70
Max. 109,00 43,90 71,50 28,50 97,30 41,80 75,30

Figure 2 – Dimensions of low-profile PQI-cores
Table 2 – Dimensions of low-profile PQI-cores
A B B C D E F G J L
1 2
Size
mm mm mm mm mm mm mm mm mm mm
Min. 16,10 5,30 2,25 10,90 2,90 14,10 6,80 9,60
PQI 16/7,8    No  m  .         3,90 8,40
Max. 16,70 5,50 2,45 11,50 3,20 14,70 7,20 10,40
Min. 20,10 5,90 2,85 13,60 2,90 17,60 8,60 12,00
PQI 20/9 Nom.     4,80 10,50
Max. 20,90 6,10 3,05 14,40 3,20 18,40 9,00 12,50
Min. 26,05 7,20 4,10 18,55 2,95 22,05 11,80 15,50
PQI 26/12 Nom.     7,30 13,90
Max. 26,95 7,40 4,30 19,45 3,25 22,95 12,20 16,50

– 10 – IEC 63093-13:2019 © IEC 2019
Table 3 – Effective parameter and A values for PQ-cores
min
a
C C A l V A
1 2 e e e min
Size
－1 －3 －3 2 3 2
mm × 10 mm mm mm mm mm
PQ16/11,6 0,633 82 14,958 42,4 26,9 1 140 38,5
PQ 20/16 0,580 53 9,034 6 64,3 37,3 2 400 59,3
PQ 20/20 0,709 95 11,129 63,8 45,3 2 890 59,3
PQ 26/20 0,361 41 2,932 5 123 44,5 5 490 113
PQ 26/25 0,437 83 3,569 9 123 53,7 6 590 113
PQ 32/20 0,313 14 2,001 2 156 49,0 7 670 142
PQ 32/30 0,440 40 2,833 3 155 68,5 10 600 142
PQ 35/35 0,465 38 2,718 8 171 79,7 13 600 161
PQ 40/40 0,491 97 2,602 7 189 93,0 17 600 174
PQ 50/50 0,342 34 1,032 6 332 113 37 600 314
PQ 65/54 0,209 36 0,355 40 589 123 72 700 531
PQ 78/39 0,256 49 0,577 90 444 114 50 500 386
PQ 107/87 0,14135 0,098 530 1 430 203 291 000 1 320
a
See IEC 60205.
Table 4 – Effective parameter and A values for low-profile PQI-cores
min
a
C C A l V A
1 2 e e e min
Size
－1 －3 －3 2 3 2
mm X 10 mm mm mm mm mm
PQI 16/7,8 0,466 78 11,185 41,7 19,5 814 37,4
PQI 20/9 0,345 95 5,238 7 66,0 22,8 1 510 59,3
PQI 26/12 0,224 03 1,814 3 123 27,7 3 420 110
a
See IEC 60205.
Figure 3 – Main dimensions of coil formers for PQ-cores
Table 5 – Dimensional limits for coil formers for PQ-cores
d d d h h a b h
1 2 3 1 2 3
Size mm mm mm mm mm mm mm mm
Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Max. Max. Min.
PQ16/11,6 13,55 13,95 8,87 9,07 7,07 7,27 6,00 6,35 4,95 5,60 19,15 20,45 6,1
PQ 20/16 17,05 17,45 10,85 11,05 9,05 9,25 9,60 9,95 8,55 9,20 23,35 23,35 6,1
PQ 20/20 17,05 17,45 10,85 11,05 9,05 9,25 13,60 13,95 12,55 13,20 23,35 23,35 6,1
PQ 26/20 21,35 21,85 14,15 14,45 12,25 12,55 10,80 11,15 9,75 10,40 26,95 29,65 6,1
PQ 26/25 21,35 21,85 14,15 14,45 12,25 12,55 15,40 15,75 14,35 15,00 26,95 29,65 6,1
PQ 32/20 26,35 26,85 15,85 16,15 13,85 14,15 10,80 11,15 9,65 10,30 32,35 34,35 6,6
PQ 32/30 26,35 26,85 15,85 16,15 13,85 14,15 20,35 20,95 19,20 20,10 32,35 34,35 6,6
PQ 35/35 30,85 31,35 16,65 17,05 14,75 15,05 24,05 24,60 22,90 23,95 35,55 39,45 7,1
PQ 40/40 35,75 36,25 17,35 17,65 15,45 15,75 28,55 29,05 27,40 28,20 41,30 42,45 6,1
PQ 50/50 42,65 43,15 22,95 23,45 20,55 21,05 34,75 35,25 33,50 34,30 51,00 51,25 9,6
PQ 65/54 51,35 51,85 29,05 29,55 26,65 27,15 34,45 34,95 33,20 34,00
PQ 78/39 68,45 68,95 28,60 29,10 26,20 26,70 24,15 24,65 22,90 23,70
PQ107/87 93,05 93,55 44,40 44,90 42,00 42,50 53,95 54,45 52,70 53,50

– 12 – IEC 63093-13:2019 © IEC 2019

Figure 4 – Pin locations and base outlines viewed from the upper side of the board
5 Mounting
Due to their sizes and respective weights, it is recommended that the cores above PQ 35/35
(including PQ 35/35) be fixed on the printed board with mounting assemblies at two opposite
sides of their coil formers.
Concerning low-profile PQI-cores, no mounting assemblies are defined. It is recommended
that the two cores be fixed by glue or adhesive tape.
6 Definitions and limits of surface irregularities
6.1 General
Surface irregularities are defined in IEC 60424-1.
6.2 Examples of surface irregularities
Figure 5 shows different examples of surface irregularities on a PQ-core.

Figure 5 – Examples of surface irregularities
6.3 Chips and ragged edges
6.3.1 General
The minimum chipping area is taken as 0,5 mm , to be distinguishable to the naked eye.
The maximum chipping area is taken as 50 mm , to be referenced to the design for the cores.
6.3.2 Chips and ragged edges located on the mating surface
The areas of the chips located on the mating surface (see C1 and C1’ irregularities in Figure 6)
shall not exceed the following limits:
– the cumulative area of the chips located on the mating surface shall be less than 4 % of
the total mating surface;
– the cumulative area of the chips located on the centre pole mating surface shall be less
than 2 % of the total mating surface;
– the cumulative area of the chips located on the mating surface of one outer leg shall be
less than 1 % of the total mating surface.
The total length of the ragged edges shall be less than 25 % of the perimeter of the relevant
mating surface.
– 14 – IEC 63093-13:2019 © IEC 2019
6.3.3 Chips and ragged edges located on the other surfaces
The areas of the chips located on the other surfaces (see C2, C2’, C3 and C3’ irregularities in
Figure 6) shall not exceed the following limits:
– the allowable chipping areas are doubled as compared to the limits for the whole mating
surfaces (see Table B.1);
– the rule for the ragged edges is the same as for the mating surfaces;
– chips and ragged edges are not acceptable on the inner edges of the wire slot area.

Figure 6 – Chips and ragged edges locations
The limits for allowable chipping areas of PQ-cores are given in Annex B.
The area and length reference of irregularities for visual inspection are given in Table 6.

Table 6 – Area and length reference of irregularities for visual inspection

– 16 – IEC 63093-13:2019 © IEC 2019
6.4 Cracks
Figure 7 shows examples of cracks locations on PQ-cores:
– a single crack which intersects the perimeter of the relevant surface at two points is not
acceptable (see S1 in Figure 7);
– the number of cracks located on the same surface shall not exceed three.
The limits of cracks at various locations shown in Figure 7 are given in Table 7.

NOTE S1 to S9: types of cracks (for limits for cracks, see Table 7).
Figure 7 – Cracks locations
Table 7 – Limits for cracks
Limits for multiple
a
Type Location Limits for single crack
cracks
S1 Any place Not acceptable Not acceptable
S2 Outer wall 20 % × W 40 % × W
S3 Mating surface of outer legs 20 % × W 40 % × W
S4 Mating surface of centre pole 20 % × F 40 % × F
S5 Bottom surface 25 % × T 50 % × T
S6 Back wall 25 % × T 50 % × T
S7 Centre pole wall 20 % × F 40 % × F
S8 Back surface 25 % × W 50 % × W
S9 Back surface 20 % × W 40 % × W
For, F, T, W, see Figure 7.
a
See Figure 7.
6.5 Pull-out
Figure 8 shows an example of a pull-out location on the PQ-core.
The cumulative area of the pull-out located on the bottom surface shall be less than 25 % of
the total respective surface area.

Figure 8 – Pull-out location
6.6 Crystallites
Figure 9 shows an example of crystallite location on the PQ-core:
– the single area of the crystallite 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.
Figure 9 – Crystallite location
6.7 Flash
Figure 10 shows an example of flash location on the PQ-core:
– with chamfering around the back surface, the flash height shall not exceed the back
surface of the core;
– without chamfering around the back surface, the flash is not acceptable.

– 18 – IEC 63093-13:2019 © IEC 2019

Figure 10 – Flash location
6.8 Pores
Figure 11 shows an example of pore location on the PQ-core:
– 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.

Figure 11 – Pore location
Annex A
(informative)
PQ-cores design
The design of PQ-cores standardized by the IEC is based on the following considerations:
a) Minimize design “q” (l /A × l /A ) with a uniform cross-section area of each magnetic
e e w w
path:
where
l is the average length of turns;
w
A is the available winding cross-section.
w
One useful way to consider ferrite core design is by evaluating the design factor “q”.
Minimize “q” results in the highest inductance and lowest copper losses in the transformer
or inductor. PQ-cores dimensions in this document are based on this type of design
philosophy.
b) Get more transmission power from the transformer assembly or real estate compared with
similar size cores.
c) Be able to take out the innermost wire without crossing other wires.
There are no base plates on the sides of the centre pole area. The innermost wire in the
coil can be taken out directly, making it easier to support the specified withstand voltage
of transformers.
d) The outside legs cover the coil former more than E-cores.
PQ-cores cover the coil former by more than 40 %, resulting in a good magnetic shielding
effect.
– 20 – IEC 63093-13:2019 © IEC 2019
Annex B
(informative)
Examples of allowable areas of chips
Information on allowable areas of chips for a given core is summarized in Table B.1.
NOTE Table B.1 is taken from IEC 60424-8:2015, Table 1, and is included in Annex B for ease of reference.
Table B.1 – Allowable areas of chips in mm
Chipping on Chipping on
Overall chipping Overall chipping
Core size mating surface of mating surface of
on mating surface on other surfaces
one outer leg centre pole
PQ16/11,6 < 1,0 < 2,0 < 3,5 < 6,5
PQ20/16 < 1,0 < 2,0 < 4,5 < 9,0
PQ20/20 < 1,0 < 2,0 < 4,5 < 9,0
PQ26/20 < 2,0 < 4,5 < 9,5 < 19,0
PQ26/25 < 2,0 < 4,5 < 9,5 < 19,0
PQ32/20 < 3,0 < 6,0 < 12,0 < 24,0
PQ32/30 < 3,0 < 6,0 < 12,0 < 24,0
PQ35/35 < 3,0 < 6,5 < 13,0 < 26,0
PQ40/40 < 3,5 < 7,0 < 14,0 < 28,0
PQ50/50 < 6,0 < 12,5 < 25,0 < 50,0
PQ65/54 < 12,5 < 24,5 < 49,0 < 50,0
PQ78/39 < 10,5 < 20,5 < 41,0 < 50,0
PQ107/87 < 27,5 < 50,0  < 50,0 < 50,0

Annex C
(normative)
Example of a gauge to check the dimensions of PQ-cores
meeting the primary dimensions
C.1 General
The gauges shall be in accordance with Figure C.1 and Table C.1.

Figure C.1 – Gauge dimensions
Table C.1 – Gauge dimensions
a b c d e f
mm mm mm mm mm mm
Size
Min. Max. Min. Max. Min. Max. Max. Min. Max. Min. Max.
PQ 16 16,705 16,715 7,50 7,60 11,505 11,515 2,90 14,085 14,095 7,205 7,215
PQ 20 20,905 20,915 12,20 12,30 14,405 14,415 2,90 17,585 17,595 9,005 9,015
PQ 26 26,955 26,965 14,50 14,60 19,455 19,465 2,95 22,035 22,045 12,205 12,215
PQ 32 32,505 32,515 17,30 17,40 22,505 22,515 5,60 26,985 26,995 13,705 13,715
PQ 35 35,705 35,715 19,50 19,60 26,505 26,515 12,35 31,485 31,495 14,605 14,615
PQ 40 41,305 41,315 22,00 22,10 28,605 28,615 14,60 36,385 36,395 15,205 15,215
PQ 50 51,005 51,015 27,10 27,20 32,505 32,515 17,90 43,285 43,295 20,355 20,365
PQ 65 66,305 66,315 29,20 29,30 40,805 40,815 17,75 51,985 51,995 26,455 26,465
PQ 78 80,005 80,015 21,95 22,05 42,805 42,815 12,60 69,085 69,095 26,005 26,015
PQ 107 109,005 109,015 45,90 46,00 71,505 71,515 27,50 93,685 93,695 41,805 41,815

– 22 – IEC 63093-13:2019 © IEC 2019
C.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 mating surface of the outer legs of the core
under test.
___________
– 24 – IEC 63093-13:2019 © IEC 2019
SOMMAIRE
AVANT-PROPOS . 26
1 Domaine d'application . 28
2 Références normatives . 28
3 Termes et définitions . 28
4 Dimensions essentielles . 29
4.1 Généralités . 29
4.2 Dimensions des noyaux PQ . 29
4.2.1 Dimensions principales . 29
4.2.2 Valeurs des paramètres effectifs et de A . 29
min
4.3 Limites dimensionnelles des supports de bobine . 29
4.4 Emplacements des broches et encombrements de base . 29
4.5 Diamètre des broches . 29
5 Montage . 35
6 Définitions et limites des irrégularités de surface . 35
6.1 Généralités . 35
6.2 Exemples d'irrégularités de surface . 35
6.3 Eclats et bords ébréchés . 35
6.3.1 Généralités . 35
6.3.2 Eclats et bords ébréchés situés sur la surface de contact . 35
6.3.3 Eclats et bords ébréchés situés sur d'autres surfaces . 36
6.4 Fissures . 38
6.5 Collage . 39
6.6 Cristallites . 39
6.7 Bavures . 39
6.8 Pores . 40
Annexe A (informative) Conception des noyaux PQ . 41
Annexe B (informative) Exemples de surfaces où les éclats sont admissibles . 42
Annexe C (normative) Exemple de calibre pour vérifier les dimensions des noyaux PQ
satisfaisant aux dimensions essentielles . 43
C.1 Généralités . 43
C.2 Procédure et exigences . 44

Figure 1 – Dimensions des noyaux PQ . 30
Figure 2 – Dimensions des noyaux PQI extra plats . 31
Figure 3 – Dimensions principales des supports de bobine pour les noyaux PQ . 33
Figure 4 – Emplacements des broches et encombrements de base vus du dessus de la
carte . 34
Figure 5 – Exemples d'irrégularités de surface . 35
Figure 6 – Emplacements des éclats et des bords ébréchés . 36
Figure 7 – Emplacements des fissures . 38
Figure 8 – Emplacement d'un collage. 39
Figure 9 – Emplacement d'une cristallite . 39
Figure 10 – Emplacement d'une bavure . 40
Figure 11 – Emplacement d'un pore . 40
Figure C.1 – Dimensions des calibres . 43

Tableau 1 – Dimensions des noyaux PQ . 30
Tableau 2 – Dimensions des noyaux PQI extra plats . 32
Tableau 3 – Valeurs des paramètres effectifs et de A pour les noyaux PQ. 32
min
Tableau 4 – Valeurs des paramètres effectifs et de A pour les noyaux PQI extra
min
plats . 32
Tableau 5 – Limites dimensionnelles des supports de bobine pour les noyaux PQ . 33
Tableau 6 – Surfaces et longueurs de référence des irrégularités pour l'inspection
visuelle . 37
Tableau 7 – Limites des fissures . 38
Tableau B.1 – Surfaces admettant des éclats en mm . 42
Tableau C.1 – Dimensions des calibres . 43

– 26 – IEC 63093-13:2019 © IEC 2019
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
NOYAUX FERRITES – LIGNES DIRECTRICES RELATIVES AUX
DIMENSIONS ET AUX LIMITES DES IRRÉGULARITÉS DE SURFACE –

Partie 13: Noyaux PQ
AVANT-PROPOS
1) La Commission Electrotechnique Internationale (IEC) est une organisation mondiale de normalisation
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2) Les décisions ou accords officiels de l'IEC concernant les questions techniques représentent, dans la mesure
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...