IEC 60740-1:2005

Laminations for transformers and inductors - Part 1: Mechanical and electrical characteristics

IEC 60740-1:2005 specifies the characteristics of laminations. Their preferred use is cores for transformers and inductors. The laminations are made of sheets and strips of magnetic materials, specified in IEC 60404-8-4 and IEC 60404-8-7. The main changes are listed below:
a) ranges with lamination strips YS, YSUI 1, YSUI 2 and laminations YEE 2-..L added;
b) range YEI 1 extended at the above end;
c) ranges YED 2, YEF 2, YEL 2, YES 2, Type YM 1-5a and YM 1-7a cancelled;
d) national designations cancelled;
e) electrical characteristics for the laminations specified;
f) mechanical characteristics for laminations added;
g) holes added for lamination types YEI 1, YUI 1, YUI 2, YM 1;
h) in Annex A, a conversion of the polarisation J and the field strength H in a specific total apparent power is defined. For the characteristics of the reactive power and the power loss, equations and constants are specified.

Tôles découpées pour transformateurs et inductances - Partie 1: Caractéristiques électriques et mécaniques

La CEI 60740-1:2005 spécifie les caractéristiques de tôles découpées. Leur utilisation préférentielle porte sur les noyaux de transformateur et d'inductances. Les tôles découpées sont constituées de bandes et de tôles de matériaux magnétiques, spécifiées dans la CEI 60404-8-4 et la CEI 60404-8-7. Les principales modifications sont présentées ci-après:
a) gammes avec bandes de tôles découpées YS, YSUI 1, YSUI 2 et tôles découpées YEE 2 -..L ajoutées;
b) gamme YEI 1 étendue aux fins de la présente norme;
c) gammes YED 2, YEF 2, YEL 2, YES 2, Type YM 1-5a et YM 1-7a annulées;
d) désignations nationales annulées;
e) caractéristiques électriques pour les tôles découpées spécifiées;
f) caractéristiques mécaniques pour les tôles découpées ajoutées;
g) trous ajoutés pour les tôles découpées de type YEI 1, YUI 1, YUI 2 et YM 1;
h) conversion de la polarisation J et de l'intensité du champ H en une puissance apparente totale spécifique définie à l'Annexe A. Des équations et des constantes sont spécifiées pour les caractéristiques de la puissance réactive et de la perte de puissance.

General Information

• Status: Published
• Publication Date: 08-Aug-2005
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.100.10 - Magnetic components
• Technical Committee: TC 51 - Magnetic components, ferrite and magnetic powder materials
• Current Stage: PPUB - Publication issued
• Start Date: 30-Nov-2005
• Completion Date: 09-Aug-2005

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD 60740-1
First edition
2005-08
Laminations for transformers and inductors –
Part 1:
Mechanical and electrical characteristics

Reference number
Publication numbering
As from 1 January 1997 all IEC publications are issued with a designation in the
60000 series. For example, IEC 34-1 is now referred to as IEC 60034-1.
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edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the base publication, the
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INTERNATIONAL IEC
STANDARD 60740-1
First edition
2005-08
Laminations for transformers and inductors –
Part 1:
Mechanical and electrical characteristics
 IEC 2005  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: [phone] Telefax: [phone] E-mail: [e-mail] Web: www.iec.ch
PRICE CODE
Commission Electrotechnique Internationale XA
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue

– 2 – 60740­1 ¤ IEC:2005(E)
CONTENTS
FOREWORD .6
1 Scope .8
2 Normative references.8
3 Terms, definitions and symbols .9
4 Materials and lamination thicknesses. 13
4.1 Materials. 13
4.2 Nominal lamination thickness . 13
4.3 Minimum stacking factor . 14
5 Designation of laminations and lamination strips . 14
5.1 Specified complete shapes. 14
5.2 Lamination strips for specified shapes. 15
5.3 Lamination strips for non­specified laminations. 16
6 Packing and marking. 16
7 Electrical tests. 16
7.1 General . 16
7.2 Core constants . 16
7.3 Magnetic path length . 17
7.4 Core cross­section. 17
8 General conditions for electrical measurements . 18
8.1 Atmospheric conditions . 18
8.2 Test coils . 18
8.3 Test cores. 18
8.4 Harmonic content of the voltage . 18
9 Measurements at high field strength . 18
9.1 General . 18
9.2 Measurement of power loss. 19
9.3 Measurement of total apparent power . 21
10 Measurements at low and medium field strength . 22
10.1 General . 22
10.2 Measurement of amplitude permeability . 22
11 Preferred ranges of laminations . 23
12 Dimensions and tolerances . 24
12.1 Dimensions . 24
12.2 Tolerances. 24
12.3 Symmetry tolerances . 25
13 Dimensions and effective parameters. 25
13.1 General . 25
13.2 Lamination strips Type YS. 25
13.3 Laminations Type YEI 1 . 26
13.4 Laminations Type YUI 1 . 27
13.5 Lamination Types YUI 2 . 30
13.6 Lamination Types YEx 2, YEE 2 and YEI 2. 32
13.7 Lamination Types YEE 2­.L . 33
13.8 Lamination Types YEx 3, YEE 3, YEF 3, YEI 3 and YEL 3. 35

60740­1 ¤ IEC:2005(E) – 3 –
13.9 Lamination Types YEx 4, YEE 4 and YEF 4. 36
13.10Laminations Type YM 1. 38
14 Electrical characteristics for materials . 39
15 Specific total apparent power for laminations . 40
16 Specific power loss for laminations. 41
17 Mechanical characteristics for laminations . 42
17.1 General appearance and conditions . 42
17.2 Cut and punch edge. 42
17.3 Camber. 43
17.4 Distortion . 43
17.5 Bending . 43
17.6 Insulation. 43
17.7 Welding . 44
Annex A (informative)    Conversion of polarisation and field strength into specific
total apparent power . 45
A.1 Specific total apparent power from polarisation and field strength. 45
A.2 Equations for the curves of the magnetic materials. 49
A.3 Constants for non­oriented silicon steel C 21 . 50
A.4 Specific reactive power and specific power loss for non­oriented silicon steel
C 21. 52
A.5 Constants for grain­oriented silicon steel C 22 . 54
A.6 Specific reactive power and specific power loss for grain­oriented silicon steel
C 22. 56
A.7 Influence of the shape on the electrical characteristics for grain­oriented silicon steel
C 22 .58
Bibliography . 59
Figure 1 – Measurements at high field strength, direct and indirect method,    single­
phase cores. 20
Figure 2 – Measurements at high field strength, direct method, three­phase cores. 21
Figure 3 – Measurements at low and medium field strength . 23
Figure 4 – Lamination strips Type YS, dimensions and tolerances. 25
Figure 5 – Laminations Type YEI 1, dimensions . 26
Figure 6 – Laminations Type YUI 1, dimensions. 28
Figure 7 – Layer plan for the lamination strip shapes Type YSUI 1 . 29
Figure 8 – Laminations Type YUI 2, dimensions. 30
Figure 9 – Layer plan for the lamination strip shapes Type YSUI 2 . 32
Figure 10 – Laminations Type YEx 2, dimensions. 32
Figure 11 – Laminations Type YEE 2­.L, using two long E parts, dimensions. 34
Figure 12 – Laminations Type YEx 3, dimensions. 35
Figure 13 – Laminations Type YEx 4, dimensions. 36
Figure 14 – Laminations Type YM 1, dimensions. 38
Figure 15 – Definition and limit of camber . 43
Figure 16 – Definition and limit of distortion. 43
Figure 17 – Definition and limit of bending. 43

– 4 – 60740­1 ¤ IEC:2005(E)
Figure A.1 – Specific total apparent power for non­oriented silicon steel C 21 . 48
Table 1 – Preferred magnetic steel and alloys used for laminations. 13
Table 2 – Material and lamination thickness. 13
Table 3 – Tolerance of the thickness of laminations . 14
Table 4 – Lamination thickness and stacking factor . 14
Table 5 – Test conditions for the materials C 21, C 22 and F 1 for power loss and
total apparent power . 19
Table 6 – Conditions for the measurement of amplitude permeability of cores using
laminations of silicon steel . 22
Table 7 – Conditions for the measurement of amplitude permeability of cores using
laminations of nickel­iron alloys . 23
Table 8 – Summary of preferred shapes . 24
Table 9 – Tolerance according to ISO 286­1 . 24
Table 10 – Tolerances for lamination strips. 25
Table 11 – Laminations Type YEI 1, relation factor    of dimensions and tolerances . 27
Table 12 – Laminations Type YEI 1, diameter of the holes and tolerance factor x. 27
Table 13 – Laminations Type YUI 1, relation of dimensions and tolerances. 28
Table 14 – Laminations Type YUI 1, diameter of the
...

IEC 60740-1 ®
Edition 1.0 2005-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Laminations for transformers and inductors –
Part 1: Mechanical and electrical characteristics

Tôles découpées pour transformateurs et inductances –
Partie 1: Caractéristiques électriques et mécaniques

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IEC 60740-1 ®
Edition 1.0 2005-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Laminations for transformers and inductors –
Part 1: Mechanical and electrical characteristics

Tôles découpées pour transformateurs et inductances –
Partie 1: Caractéristiques électriques et mécaniques

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XA
ICS 29.100.10 ISBN 978-2-88912-783-2

– 2 – 60740-1  IEC:2005
CONTENTS
FOREWORD . 6
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and sy mbols . 9
4 Materials and lamination thickn es s e s . 13
4.1 Materials . 13
4.2 Nominal lamination thickness . 13
4.3 Minimum stacking factor . 14
5 Designation of laminations and lamination strips . 14
5.1 Specified complete shapes . 14
5.2 Lamination strips for specified shapes . 15
5.3 Lamination strips for non-specified laminations . 16
6 Packing and marking . 16
7 Electrical tests . 16
7.1 General . 16
7.2 Core constants . 16
7.3 Magnetic path length . 17
7.4 Core cross-section . 17
8 General conditions for electrical measurements . 18
8.1 Atmospheric conditions . 18
8.2 Test coils . 18
8.3 Test cores . 18
8.4 Harmonic content of the voltage . 18
9 Measurements at high field strength . 18
9.1 General . 18
9.2 Measurement of power loss . 19
9.3 Measurement of total apparent power . 21
10 Measurements at low and medium field strength . 22
10.1 General . 22
10.2 Measurement of amplitude permeability . 22
11 Preferred ranges of laminations . 23
12 Dimensions and tolerances . 24
12.1 Dimensions . 24
12.2 Tolerances . 24
12.3 Symmetry tolerances . 25
13 Dimensions and effective parameters . 25
13.1 General . 25
13.2 Lamination strips Type YS . 25
13.3 Laminations Type YEI 1 . 26
13.4 Laminations Type YUI 1 . 27
13.5 Lamination Types YUI 2 . 30
13.6 Lamination Types YEx 2, YEE 2 and YEI 2 . 32
13.7 Lamination Types YEE 2-.L . 33
13.8 Lamination Types YEx 3, YEE 3, YEF 3, YEI 3 and YEL 3 . 35

60740-1  IEC:2005 – 3 –
13.9 Lamination Types YEx 4, YEE 4 and YEF 4 . 36
13.10 Laminations Type YM 1 . 38
14 Electrical characteristics for mate rials . 39
15 Specific total apparent power for laminations . 40
16 Specific power loss for laminations . 41
17 Mechanical characteristics for laminations . 42
17.1 General appearance and conditi ons . 42
17.2 Cut and punch edge . 42
17.3 Camber . 43
17.4 Distortion . 43
17.5 Bending . 43
17.6 Insulation . 43
17.7 Weldin g . 44

Annex A (informative) Conversion of polarisation and field strength into specific total
apparent power . . 45
A.1 Specific total apparent power from polarisation and field strength . 45
A.2 Equations for the curves of the magnetic materials . 49
A.3 Constants for non-oriented silicon steel C 21 . 50
A.4 Specific reactive power and specific power loss for non-oriented silicon steel C 21 . 52
A.5 Constants for grain-oriented silicon steel C 22 . 54
A.6 Specific reactive power and specific power loss for grain-oriented silicon steel

C 22 . . 56
A.7 Influence of the shape on the electrical characteristics for grain-oriented silicon steel C 22 . 58

Bibliography . . 59

Figure 1 – Measurements at high field strength, direct and indirect method, single-
phase cores . 20
Figure 2 – Measurements at high field strength, direct method, three-phase cores . 21
Figure 3 – Measurements at low and medium field strength . 23
Figure 4 – Lamination strips Type YS, dimensions and tolerances . 25
Figure 5 – Laminations Type YEI 1, dimensions . 26
Figure 6 – Laminations Type YUI 1, dimensions . 28
Figure 7 – Layer plan for the lamination strip shapes Type YSUI 1 . 29
Figure 8 – Laminations Type YUI 2, dimensions . 30
Figure 9 – Layer plan for the lamination strip shapes Type YSUI 2 . 32
Figure 10 – Laminations Type YEx 2, dim
...