IEC 60738-1:2006

Thermistors - Directly heated positive temperature coefficient - Part 1: Generic specification

IEC 60738-1:2006 describes terms and methods of test for positive step-function temperature coefficient thermistors, insulated and non-insulated types typically made from ferro-electric semi-conductor materials. It establishes standard terms, inspection procedures and methods of test for use in detail specifications for Qualification Approval and for Quality Assessment Systems for electronic components. This third edition cancels and replaces the second edition published in 1998 and constitutes a minor revision. The changes with respect to the previous edition refer to the tables, figures and references.

Thermistances - Coefficient de température positif à chauffage direct - Partie 1: Spécification générique

L'IEC 60738-1:2006 décrit des termes et des méthodes d'essais pour les thermistances à basculement à coefficient de température positif, de type isolés ou non isolés, normalement fabriqués à partir de matériaux semiconducteurs ferroélectriques. Elle établit des termes normalisés, des procédures de contrôle et des méthodes d'essais destinés aux spécifications particulières pour l'homologation et pour les systèmes d'assurance de la qualité des composants électroniques. Cette troisième édition annule et remplace la deuxième édition parue en 1998 dont elle constitue une révision mineure. Les modifications par rapport à l'édition antérieure portent sur les tableaux, les figures et les références.

General Information

• Status: Published
• Publication Date: 29-Jul-2009
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 31.040.30 - Thermistors
• Technical Committee: TC 40 - Capacitors and resistors for electronic equipment
• Current Stage: DELPUB - Deleted Publication
• Start Date: 30-Apr-2021
• Completion Date: 14-Oct-2022

Relations

• Amended By: IEC 60738-1:2006/AMD1:2009 - Amendment 1 - Thermistors - Directly heated positive temperature coefficient - Part 1: Generic specification
• Effective Date: 05-Sep-2023
• Revises: IEC 60738-1:1998 - Thermistors - Directly heated positive step-function temperature coefficient - Part 1: Generic specification
• Effective Date: 05-Sep-2023
• Revised: IEC 60738-1:2022 - Thermistors - Directly heated positive temperature coefficient - Part 1: Generic specification
• Effective Date: 05-Sep-2023

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD 60738-1
QC 440000
Third edition
2006-04
Thermistors – Directly heated positive
temperature coefficient –
Part 1:
Generic specification
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.

Consolidated editions
The IEC is now publishing consolidated versions of its publications. For example,

edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the base publication, the
base publication incorporating amendment 1 and the base publication incorporating
amendments 1 and 2.
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thus ensuring that the content reflects current technology. Information relating to
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Information on the subjects under consideration and work in progress undertaken
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INTERNATIONAL IEC
STANDARD 60738-1
QC 440000
Third edition
2006-04
Thermistors – Directly heated positive
temperature coefficient –
Part 1:
Generic specification
 IEC 2006  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 – 60738-1  IEC:2006(E)
CONTENTS
FOREWORD.5

1 Scope.7

2 Normative references .7

3 Terms and definitions .8

4 Units and symbols .16

5 Preferred values.17

5.1 Climatic categories.17
5.2 Marking .17
5.3 Spacings .18
6 Quality assessment procedures.18
6.1 General .18
6.2 Primary stage of manufacture.19
6.3 Subcontracting .19
6.4 Structurally similar components.19
6.5 Qualification approval procedures .20
6.6 Rework and repair .27
6.7 Release for delivery .27
6.8 Certified test records of released lots .28
6.9 Delayed delivery.28
6.10 Alternative test methods .28
6.11 Manufacture outside the geographical limits of IECQ NSIs .28
6.12 Unchecked parameters.28
7 Test and measurement procedures.28
7.1 General .28
7.2 Standard conditions for testing .29
7.3 Drying and recovery .29
7.4 Visual examination and check of dimensions.30
7.5 Zero-power resistance.30
7.6 Temperature coefficient of resistance.31
7.7 Insulation resistance (for insulated types only) .31
7.8 Voltage proof (for insulated types only) .32

7.9 Resistance/temperature characteristic.32
7.10 Dissipation factor at U (δ) .33
max
7.11 Response time by ambient temperature change (t ) .34
a
7.12 Response time by power change (t ).34
p
7.13 Thermal time constant by ambient temperature change (τ ) .35
a
7.14 Thermal time constant by cooling (τ ).35
c
7.15 Robustness of terminations .37
7.16 Solderability .38
7.17 Resistance to soldering heat .39
7.18 Rapid change of temperature .40
7.19 Vibration.40
7.20 Bump .40
7.21 Shock.41

60738-1  IEC:2006(E) – 3 –
7.22 Climatic sequence .41

7.23 Damp heat, steady state.42

7.24 Endurance.43

7.25 Tripping current and tripping time .46

7.26 Non-tripping current .47

7.27 Residual current .47

7.28 Surface temperature.47

7.29 Inrush current.48

7.30 Mounting (for surface mount thermistors only) .49

7.31 Shear (adhesion) test .50

7.32 Substrate bending test .50

Annex A (normative) Interpretation of sampling plans and procedures as described in
IEC 60410 for use within the IEC quality assessment system for electronic
components (IECQ) .51
Annex B (informative) Mounting for electrical measurements (except surface mount
types) .52
Annex C (informative) Mounting for temperature measurements .55

Figure 1 – Typical resistance-temperature characteristic and definitions for PTC
thermistors (at zero power) .10
Figure 2 – Typical R-TNF characteristic for PTC thermistors in sensor applications .11
Figure 3 – Typical current/voltage characteristic for PTC thermistors .11
Figure 4 – I against t at U .14
in dc
Figure 5 – I against t at U .15
in rms
Figure 6 – Dissipation factor test circuit .33
Figure 7 – Temperature gradient.34
Figure 8 – Circuit for measurement of thermal time constant by cooling.36
Figure 9 – Circuit for endurance at maximum operating temperature and maximum
voltage.45
Figure 10 – Circuit for surface temperature measurement.48
Figure 11 – Measuring circuit.48
Figure B.1 – Example of a preferred mounting method for thermistors without wire
terminations.52

Figure B.2 – Example of a preferred mounting method for thermistors with wire
terminations.53
Figure B.3 – Example of a preferred mounting method for surface mount thermistors .54
Figure C.1 – Example of a preferred mounting method for temperature measurement
on cylindrical heating elements .55

Table 1 – Creepage distances and clearances .18
Table 2 – Fixed sample size test schedule for qualification approval of thermistors for
current limitation – Assessment level EZ.22
Table 3 – Fixed sample size test schedule for qualification approval of thermistors for
use as heating elements – Assessment level EZ.23
Table 4 – Fixed sample size test schedule for qualification approval of thermistors for
inrush current application – Assessment level EZ .24
Table 5 – Fixed sample size test schedule for qualification approval of thermistors for
use as temperature sensing elements, Assessment level EZ .25

– 4 – 60738-1  IEC:2006(E)
Table 6 – Quality conformance inspection for lot-by-lot inspection .26

Table 7 – Quality conformance inspection for periodic testing .27

Table 8 – Tensile force .37

Table 9 – Number of cycles per climatic category .42

60738-1  IEC:2006(E) – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
THERMISTORS – DIRECTLY HEATED POSITIVE

TEMPERATURE COEFFICIENT –
Part 1: Generic specification
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
international co-operation on all questions concerning standardization in the electrical and
...

IEC 60738-1 ®
Edition 3.1 2009-07
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
QC 440000
Thermistors – Directly heated positive temperature coefficient –
Part 1: Generic specification
All rights reserved. Unless otherwise specified, 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
either IEC or IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,

please contact the address below or your local IEC member National Committee for further information.

IEC Central Office
3, rue de Varembé
CH-1211 Geneva 20
Switzerland
Email: [e-mail]
Web: www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.
ƒ Catalogue of IEC publications: www.iec.ch/searchpub
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It also gives information on projects, withdrawn and replaced publications.
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IEC 60738-1 ®
Edition 3.1 2009-07
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
QC 440000
Thermistors – Directly heated positive temperature coefficient –
Part 1: Generic specification
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
CP
ICS 31.040.30 ISBN 978-2-88910-269-3
– 2 – 60738-1 © IEC:2006+A1:2009(E)

CONTENTS
FOREWORD.5

1 Scope.7

2 Normative references .7

3 Terms and definitions .8

4 Units and symbols .16

5 Preferred values.17

5.1 Climatic categories.17
5.2 Marking .17
5.3 Spacings .18
6 Quality assessment procedures.18
6.1 General .18
6.2 Primary stage of manufacture.19
6.3 Subcontracting .19
6.4 Structurally similar components.19
6.5 Qualification approval procedures .20
6.6 Rework and repair .27
6.7 Release for delivery .27
6.8 Certified test records of released lots .28
6.9 Delayed delivery.28
6.10 Alternative test methods .28
6.11 Manufacture outside the geographical limits of IECQ NSIs .28
6.12 Unchecked parameters.28
7 Test and measurement procedures.28
7.1 General .28
7.2 Standard conditions for testing .29
7.3 Drying and recovery .29
7.4 Visual examination and check of dimensions.30
7.5 Zero-power resistance.30
7.6 Temperature coefficient of resistance.31
7.7 Insulation resistance (for insulated types only) .31
7.8 Voltage proof (for insulated types only) .32

7.9 Resistance/temperature characteristic.32
7.10 Dissipation factor at U (δ) .33
max
7.11 Response time by ambient temperature change (t ) .34
a
7.12 Response time by power change (t ).34
p
7.13 Thermal time constant by ambient temperature change (τ ) .35
a
7.14 Thermal time constant by cooling (τ ).35
c
7.15 Robustness of terminations .37
7.16 Solderability .38
7.17 Resistance to soldering heat .39
7.18 Rapid change of temperature .40
7.19 Vibration.40
7.20 Bump .40
7.21 Shock.41

60738-1 © IEC:2006+A1:2009(E) – 3 –

7.22 Climatic sequence .41

7.23 Damp heat, steady state.42

7.24 Endurance.43

7.25 Tripping current and tripping time .47

7.26 Non-tripping current .47

7.27 Residual current .47

7.28 Surface temperature.48

7.29 Inrush current.49

7.30 Mounting (for surface mount thermistors only) .49

7.31 Shear (adhesion) test .50

7.32 Substrate bending test .51

Annex A (normative) Interpretation of sampling plans and procedures as described in
IEC 60410 for use within the IEC quality assessment system for electronic components
(IECQ) .52
Annex B (informative) Mounting for electrical measurements (except surface mount
types) .53
Annex C (informative) Mounting for temperature measurements .56

Figure 1 – Typical resistance-temperature characteristic and definitions for PTC
thermistors (at zero power) .10
Figure 2 – Typical R-TNF characteristic for PTC thermistors in sensor applications .11
Figure 3 – Typical current/voltage characteristic for PTC thermistors .11
Figure 4 – I against t at U .14
in dc
Figure 5 – I against t at U .15
in rms
Figure 6 – Dissipation factor test circuit .33
Figure 7 – Temperature gradient.34
Figure 8 – Circuit for measurement of thermal time constant by cooling.36
Figure 9 – Circuit for endurance at maximum operating temperature and maximum
voltage.45
Figure 10 – Circuit for surface temperature measurement.48
Figure 11 – Measuring circuit.49
Figure B.1 – Example of a preferred mounting method for thermistors without wire
terminations.53

Figure B.2 – Example of a preferred mounting method for thermistors with wire
terminations.54
Figure B.3 – Example of a preferred mounting method for surface mount thermistors .55
Figure C.1 – Example of a preferred mounting method for temperature measurement
on cylindrical heating elements .56

Table 1 – Creepage distances and clearances .18
Table 2 – Fixed sample size test schedule for qualification approval of thermistors for
current limitation – Assessment level EZ.22
Table 3 – Fixed sample size test schedule for qualification approval of thermistors for
use as heating elements – Assessment level EZ.23
Table 4 – Fixed sample size test schedule for qualification approval of thermistors for
inrush current application – Assessment level EZ .24
Table 5 – Fixed sample size test schedule for qualification approval of thermistors for
use as temperature sensing elements, Assessment level EZ .25

– 4 – 60738-1 © IEC:2006+A1:2009(E)

Table 6 – Quality conformance inspection for lot-by-lot inspection .26

Table 7 – Quality conformance inspection for periodic testing .27

Table 8 – Tensile force .37

Table 9 – Number of cycles per climatic category .42

60738-1 © IEC:2006+A1:2009(E) – 5 –

INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
THERMISTORS – DIRECTLY HEATED POSITIVE

TEMPERATURE COEFFICIENT –
Part 1: Generic specification
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
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes
...

IEC 60738-1 ®
Edition 3.0 2006-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Thermistors – Directly heated positive temperature coefficient –
Part 1: Generic specification
Thermistances – Coefficient de température positif à chauffage direct –
Partie 1: Spécification générique

All rights reserved. Unless otherwise specified, 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
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copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
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Switzerland www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.

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IEC 60738-1 ®
Edition 3.0 2006-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Thermistors – Directly heated positive temperature coefficient –

Part 1: Generic specification
Thermistances – Coefficient de température positif à chauffage direct –

Partie 1: Spécification générique

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XA
ICS 31.040.30 ISBN 978-2-83221-336-0

– 2 – 60738-1  IEC:2006
CONTENTS
FOREWORD . 5

1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Units and symbols . 16
5 Preferred values . 17
5.1 Climatic categories . 17
5.2 Marking . 17
5.3 Spacings . 18
6 Quality assessment procedures . 18
6.1 General . 18
6.2 Primary stage of manufacture . 19
6.3 Subcontracting . 19
6.4 Structurally similar components . 19
6.5 Qualification approval procedures . 20
6.6 Rework and repair . 27
6.7 Release for delivery . 27
6.8 Certified test records of released lots . 28
6.9 Delayed delivery . 28
6.10 Alternative test methods . 28
6.11 Manufacture outside the geographical limits of IECQ NSIs . 28
6.12 Unchecked parameters . 28
7 Test and measurement procedures . 28
7.1 General . 28
7.2 Standard conditions for testing . 29
7.3 Drying and recovery . 29
7.4 Visual examination and check of dimensions . 30
7.5 Zero-power resistance . 30
7.6 Temperature coefficient of resistance . 31
7.7 Insulation resistance (for insulated types only) . 31
7.8 Voltage proof (for insulated types only) . 32
7.9 Resistance/temperature characteristic . 32
7.10 Dissipation factor at U (δ) . 33
max
7.11 Response time by ambient temperature change (t ) . 34
a
7.12 Response time by power change (t ) . 34
p
7.13 Thermal time constant by ambient temperature change (τ ) . 35
a
7.14 Thermal time constant by cooling (τ ). 35
c
7.15 Robustness of terminations . 37
7.16 Solderability . 38
7.17 Resistance to soldering heat . 39
7.18 Rapid change of temperature . 40
7.19 Vibration. 40
7.20 Bump . 40
7.21 Shock . 41

60738-1  IEC:2006 – 3 –
7.22 Climatic sequence . 41
7.23 Damp heat, steady state . 42
7.24 Endurance . 43
7.25 Tripping current and tripping time . 46
7.26 Non-tripping current . 47
7.27 Residual current . 47
7.28 Surface temperature . 47
7.29 Inrush current . 48
7.30 Mounting (for surface mount thermistors only) . 49
7.31 Shear (adhesion) test . 50
7.32 Substrate bending test . 50

Annex A (normative) Interpretation of sampling plans and procedures as described in
IEC 60410 for use within the IEC quality assessment system for electronic
components (IECQ) . 51
Annex B (informative) Mounting for electrical measurements (except surface mount
types) . 52
Annex C (informative) Mounting for temperature measurements . 55

Figure 1 – Typical resistance-temperature characteristic and definitions for PTC
thermistors (at zero power) . 10
Figure 2 – Typical R-TNF characteristic for PTC thermistors in sensor applications . 11
Figure 3 – Typical current/voltage characteristic for PTC thermistors . 11
Figure 4 – I against t at U . 14
in dc
Figure 5 – I against t at U .
...

IEC 60738-1 ®
Edition 3.1 2009-07
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Thermistors – Directly heated positive temperature coefficient –
Part 1: Generic specification
Thermistances – Coefficient de température positif à chauffage direct –
Partie 1: Spécification générique

All rights reserved. Unless otherwise specified, 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

either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or

your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie

et les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des

questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.

IEC Central Office Tel.: [phone]
3, rue de Varembé Fax: [phone]
CH-1211 Geneva 20 [e-mail]
Switzerland www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.

IEC Catalogue - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
The stand-alone application for consulting the entire The world's leading online dictionary of electronic and
bibliographical information on IEC International Standards, electrical terms containing more than 30 000 terms and
Technical Specifications, Technical Reports and other definitions in English and French, with equivalent terms in 14
documents. Available for PC, Mac OS, Android Tablets and additional languages. Also known as the International
iPad. Electrotechnical Vocabulary (IEV) online.

IEC publications search - www.iec.ch/searchpub IEC Glossary - std.iec.ch/glossary
The advanced search enables to find IEC publications by a More than 55 000 electrotechnical terminology entries in
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IEC 60738-1 ®
Edition 3.1 2009-07
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Thermistors – Directly heated positive temperature coefficient –

Part 1: Generic specification
Thermistances – Coefficient de température positif à chauffage direct –

Partie 1: Spécification générique

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.040.30 ISBN 978-2-8322-1370-4

IEC 60738-1 ®
Edition 3.1 2009-07
CONSOLIDATED VERSION
REDLINE VERSION
VERSION REDLINE
colour
inside
Thermistors – Directly heated positive temperature coefficient –
Part 1: Generic specification
Thermistances – Coefficient de température positif à chauffage direct –
Partie 1: Spécification générique

– 2 – 60738-1  IEC:2006+A1:2009

CONTENTS
FOREWORD . 5

1 Scope . 7

2 Normative references . 7

3 Terms and definitions . 8

4 Units and symbols . 16

5 Preferred values . 17

5.1 Climatic categories . 17
5.2 Marking . 17
5.3 Spacings . 18
6 Quality assessment procedures . 18
6.1 General . 18
6.2 Primary stage of manufacture . 19
6.3 Subcontracting . 19
6.4 Structurally similar components . 19
6.5 Qualification approval procedures . 20
6.6 Rework and repair . 27
6.7 Release for delivery . 27
6.8 Certified test records of released lots . 28
6.9 Delayed delivery . 28
6.10 Alternative test methods . 28
6.11 Manufacture outside the geographical limits of IECQ NSIs . 28
6.12 Unchecked parameters . 28
7 Test and measurement procedures . 28
7.1 General . 28
7.2 Standard conditions for testing . 29
7.3 Drying and recovery . 29
7.4 Visual examination and check of dimensions . 30
7.5 Zero-power resistance . 30
7.6 Temperature coefficient of resistance . 31
7.7 Insulation resistance (for insulated types only) . 31
7.8 Voltage proof (for insulated types only) . 32

7.9 Resistance/temperature characteristic . 32
7.10 Dissipation factor at U (δ) . 33
max
7.11 Response time by ambient temperature change (t ) . 34
a
7.12 Response time by power change (t ) . 34
p
7.13 Thermal time constant by ambient temperature change (τ ) . 35
a
7.14 Thermal time constant by cooling (τ ). 35
c
7.15 Robustness of terminations . 37
7.16 Solderability . 38
7.17 Resistance to soldering heat . 39
7.18 Rapid change of temperature . 40
7.19 Vibration. 40
7.20 Bump . 40
7.21 Shock . 41

60738-1  IEC:2006+A1:2009 – 3 –

7.22 Climatic sequence . 41

7.23 Damp heat, steady state . 42

7.24 Endurance . 43

7.25 Tripping current and tripping time . 47

7.26 Non-tripping current . 47

7.27 Residual current . 47

7.28 Surface temperature . 48

7.29 Inrush current . 49

7.30 Mounting (for surface mount thermistors only) . 49

7.31 Shear (adhesion) test . 50

7.32 Substrate bending test . 51

Annex A (normative) Interpretation of sampling plans and procedures as described in
IEC 60410 for use within the IEC quality assessment system for electronic
components (IECQ) . 52
Annex B (informative) Mounting for electrical measurements (except surface mount
types) . 53
Annex C (informative) Mounting for temperature measurements . 56

Figure 1 – Typical resistan
...