Electrical insulation systems - Thermal evaluation of modifications to an established electrical insulation system (EIS) - Part 1: Wire-wound winding EIS

IEC 61858-1:2014 lists the required test procedures for qualification of modifications of an established electrical insulation system (EIS) with respect to its thermal classification. This standard is applicable to EIS used in wire-wound winding electrotechnical devices. The test procedures are comparative in that the performance of a candidate EIS is compared to that of a reference EIS, which has proven service experience in accordance with IEC 60505 or has been evaluated by one of the procedures given in the IEC 61857 series. This first edition of IEC 61858-1 cancels and replaces the third edition of IEC 61858, published in 2008. It constitutes a technical and editorial revision. This edition includes the following significant technical changes with respect to the previous edition:
a) this part is specifically for wire-wound winding EIS;
b) new figures and charts support the contents.

Systèmes d'isolation électrique - Évaluation thermique des modifications apportées à un système d'isolation électrique (SIE) éprouvé - Partie 1: Système d'isolation électrique à enroulements à fils

L'IEC 61858-1:2014 énumère les procédures d'essai requises pour la qualification des modifications qui ont été apportées à un système d'isolation électrique éprouvé (SIE), pour ce qui concerne sa classification thermique. La présente norme s'applique aux SIE utilisés dans les dispositifs électrotechniques à enroulements à fils. Les procédures d'essai sont comparatives en ce qu'elles se font par comparaison des performances d'un SIE candidat avec celles d'un SIE de référence dont l'expérience en service a été démontrée conformément à l'IEC 60505, ou qui a été évalué par une des procédures décrites dans la série IEC 61857. Cette première édition de l'IEC 61858-1 annule et remplace la troisième édition de l'IEC 61858, parue en 2008. La présente édition constitue une révision technique et éditoriale. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) cette partie est spécifiquement pour bobinée enroulement SIE;
b) nouveaux chiffres et graphiques appuient le contenu.

General Information

Status
Published
Publication Date
11-Feb-2014
Current Stage
PPUB - Publication issued
Start Date
12-Feb-2014
Completion Date
12-Feb-2014
Ref Project

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IEC 61858-1
Edition 1.0 2014-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electrical insulation systems – Thermal evaluation of modifications to an
established electrical insulation system (EIS) –
Part 1: Wire-wound winding EIS
Systèmes d'isolation électrique – Évaluation thermique des modifications
apportées à un système d’isolation électrique (SIE) éprouvé –
Partie 1: Système d’isolation électrique à enroulements à fils
IEC 61858-1:2014-02(EN-FR)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 61858-1
Edition 1.0 2014-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electrical insulation systems – Thermal evaluation of modifications to an
established electrical insulation system (EIS) –
Part 1: Wire-wound winding EIS
Systèmes d'isolation électrique – Évaluation thermique des modifications
apportées à un système d’isolation électrique (SIE) éprouvé –
Partie 1: Système d’isolation électrique à enroulements à fils
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX V
ICS 29.080.30 ISBN 978-2-8322-1410-7

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – 61858-1 © IEC:2014
CONTENTS

FOREWORD ........................................................................................................................... 4

INTRODUCTION ..................................................................................................................... 6

1 Scope .............................................................................................................................. 7

2 Normative references ...................................................................................................... 7

3 Terms and definitions ...................................................................................................... 9

4 General considerations .................................................................................................. 11

5 Substitution of phase or ground insulation ..................................................................... 13

5.1 Generically identical ............................................................................................. 13

5.2 Substitution or addition of selected components and additives .............................. 13

6 Substitution of winding wire ........................................................................................... 14

6.1 Non bondable winding wire ................................................................................... 14

6.2 Bondable winding wire .......................................................................................... 15

6.3 Substitution of conductor material ......................................................................... 16

7 Substitution of impregnating resin/varnish ..................................................................... 17

7.1 Thermal class determination ................................................................................. 17

7.2 Evaluation ............................................................................................................. 18

7.2.1 Thermal classes equal or better ................................................................. 18

7.2.2 One thermal class lower ............................................................................ 18

7.2.3 Other criteria ............................................................................................. 18

8 Substitution with other EIM ............................................................................................ 18

8.1 Technically equivalent materials ........................................................................... 18

8.2 Previous evaluation .............................................................................................. 18

8.3 Other .................................................................................................................... 18

9 Evaluation of additions .................................................................................................. 19

9.1 Addition of an impregnating resin/varnish.............................................................. 19

9.2 Addition of other components ................................................................................ 19

10 Chemical compatibility of a combination of materials ..................................................... 20

10.1 General ................................................................................................................. 20

10.2 Construction ......................................................................................................... 20

10.2.1 Test apparatus .......................................................................................... 20

10.2.2 Material specimens .................................................................................... 20

10.2.3 Contents of tube ........................................................................................ 20

10.3 Test procedure...................................................................................................... 21

10.3.1 Preparation of tubes .................................................................................. 21

10.3.2 Thermal conditioning ................................................................................. 21

10.3.3 Opening procedure .................................................................................... 21

10.3.4 Evaluation of samples ............................................................................... 22

11 Single-point thermal ageing test (procedure C) .............................................................. 22

11.1 Test objects .......................................................................................................... 22

11.2 Establishing the EIS relative thermal endurance index (EIS RTE) ......................... 22

11.3 Interpretation of results ......................................................................................... 23

12 Full thermal aging test (procedure D) ............................................................................. 23

Annex A (normative) Classes of winding wire ....................................................................... 24

Annex B (informative) Visual representations of coils ........................................................... 26

B.1 Form wound coils .................................................................................................. 26

---------------------- Page: 4 ----------------------
61858-1 © IEC:2014 – 3 –

B.2 Precision-wound coil ............................................................................................. 27

B.3 Random-wound coil .............................................................................................. 28

Bibliography .......................................................................................................................... 30

Figure 1 – Overview of evaluation methods ........................................................................... 12

Figure 2 – Substitution of phase and ground insulation ......................................................... 13

Figure 3 – Substitution of non-bondable winding wire............................................................ 14

Figure 4 – Substitution of bondable winding wire .................................................................. 15

Figure 5 – Substitution of conductor material ........................................................................ 16

Figure 6 – Substitution of impregnating resin/varnish ............................................................ 17

Figure 7 – Additions of resins/varnishes and other components used in combination

with the EIMs evaluated in the EIS ........................................................................................ 19

Figure B.1 – Form-wound coil comparison ............................................................................ 26

Figure B.2 – Form-wound coil comparison – Close-up .......................................................... 26

Figure B.3 – Form-wound coil comparison – Different angle .................................................. 27

Figure B.4 – Form-wound coil detail ...................................................................................... 27

Figure B.5 – Examples of precision-wound coils ................................................................... 28

Figure B.6 – Example of precision-wound coil – Close-up ..................................................... 28

Figure B.7 – Example of random-wound coil ......................................................................... 29

Figure B.8 – Example of random-wound coil – Close-up ....................................................... 29

Table 1 – Thermal ageing test methods for resin/varnishes ................................................... 18

Table A.1 – Winding wire types – Round copper or aluminum conductor ............................... 24

---------------------- Page: 5 ----------------------
– 4 – 61858-1 © IEC:2014
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL INSULATION SYSTEMS –
THERMAL EVALUATION OF MODIFICATIONS TO
AN ESTABLISHED ELECTRICAL INSULATION SYSTEM (EIS) –
Part 1: Wire-wound winding EIS
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 International Standards, Technical Specifications,

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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 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

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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

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6) All users should ensure that they have the latest edition of this publication.

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expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

Publications.

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 61858-1 has been prepared by IEC technical committee 112:

Evaluation and qualification of electrical insulating materials and systems.

This first edition of IEC 61858-1 cancels and replaces the third edition of IEC 61858,

published in 2008. It constitutes a technical and editorial revision.

This edition includes the following significant technical changes with respect to the previous

edition:
a) this part is specifically for wire-wound winding EIS;
b) new figures and charts support the contents.
---------------------- Page: 6 ----------------------
61858-1 © IEC:2014 – 5 –
The text of this standard is based on the following documents:
CDV Report on voting
112/252/CDV 112/275/RVC

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 61858 series, published under the general title Electrical

insulation systems – Thermal evaluation of modifications to an established electrical

insulation system (EIS), 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 web site 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.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates

that it contains colours which are considered to be useful for the correct

understanding of its contents. Users should therefore print this document using a

colour printer.
---------------------- Page: 7 ----------------------
– 6 – 61858-1 © IEC:2014
INTRODUCTION

This International Standard describes procedures for the evaluation of changes to an

established electrical insulation system (EIS) for wire-wound electro technical devices and the

effect of these changes on the thermal classification of the established EIS.

This Part 1 of IEC 61858 is for wire-wound winding EIS. Part 2 of IEC 61858 addresses

modifications of form-wound winding EIS.

General principles for evaluation and qualification of EIS can be found in IEC 60505. Unless

the procedures of this standard indicate otherwise, the principles of IEC 60505 should be

followed.

The thermal classification of an EIS is established either by known service life, in accordance

with IEC 60505, or evaluated in accordance with the IEC 61857 series.
---------------------- Page: 8 ----------------------
61858-1 © IEC:2014 – 7 –
ELECTRICAL INSULATION SYSTEMS –
THERMAL EVALUATION OF MODIFICATIONS TO
AN ESTABLISHED ELECTRICAL INSULATION SYSTEM (EIS) –
Part 1: Wire-wound winding EIS
1 Scope

This part of IEC 61858 lists the required test procedures for qualification of modifications of

an established electrical insulation system (EIS) with respect to its thermal classification. This

standard is applicable to EIS used in wire-wound winding electrotechnical devices. The test

procedures are comparative in that the performance of a candidate EIS is compared to that of

a reference EIS, which has proven service experience in accordance with IEC 60505 or has

been evaluated by one of the procedures given in the IEC 61857 series.
2 Normative references

Les documents suivants sont cités en référence de manière normative, en intégralité ou en

partie, dans le présent document et sont indispensables pour son application. Pour les

références datées, seule l’édition citée s’applique. Pour les références non datées, la

dernière édition du document de référence s’applique (y compris les éventuels amendements).

IEC 60085:2007, Electrical insulation – Thermal evaluation and designation

IEC 60172, Test procedure for the determination of the temperature index of enamelled

winding wires

IEC 60216-5, Electrical insulating materials – Thermal endurance properties – Part 5:

Determination of relative thermal endurance index (RTE) of an insulating material

IEC 60317-1, Specifications for particular types of winding wires – Part 1: Polyvinyl acetal

enamelled round copper wire, class 105

IEC 60317-2, Specifications for particular types of winding wires – Part 2: Solderable

polyurethane enamelled round copper wire, class 130, with a bonding layer

IEC 60317-3, Specifications for particular types of winding wires – Part 3: Polyester

enamelled round copper wire, class 155

IEC 60317-4, Specifications for particular types of winding wires – Part 4: Solderable

polyurethane enamelled round copper wire, class 130

IEC 60317-8 Specifications for particular types of winding wires – Part 8: Polyesterimide

enamelled round copper wire, class 180

IEC 60317-12, Specifications for particular types of winding wires – Part 12: Polyvinyl acetal

enamelled round copper wire, class 120

IEC 60317-13, Specifications for particular types of winding wires – Part 13: Polyester or

polyesterimide overcoated with polyamide-imide enamelled round copper wire, class 200

---------------------- Page: 9 ----------------------
– 8 – 61858-1 © IEC:2014

IEC 60317-19, Specifications for particular types of winding wires – Part 19: Solderable

polyurethane enamelled round copper wire overcoated with polyamide, class 130
(withdrawn)

IEC 60317-20, Specifications for particular types of winding wires – Part 20: Solderable

polyurethane enamelled round copper wire, class 155

IEC 60317-21, Specifications for particular types of winding wires – Part 21: Solderable

polyurethane enamelled round copper wire overcoated with polyamide, class 155

IEC 60317-22, Specifications for particular types of winding wires – Part 22: Polyester or

polyesterimide enamelled round copper wire overcoated with polyamide, class 180

IEC 60317-23, Specifications for particular types of winding wires – Part 23: Solderable

polyesterimide enamelled round copper wire, class 180

IEC 60317-25, Specifications for particular types of winding wires – Part 25: Polyester or

polyesterimide overcoated with polyamide-imide enamelled round aluminium wire, class 200

IEC 60317-26, Specifications for particular types of winding wires – Part 26: Polyamide-imide

enamelled round copper wire, class 200

IEC 60317-34, Specifications for particular types of winding wires – Part 34: Polyester

enamelled round copper wire, class 130 L
(withdrawn)

IEC 60317-35, Specifications for particular types of winding wires – Part 35: Solderable

polyurethane enamelled round copper wire, class 155, with a bonding layer

IEC 60317-36, Specifications for particular types of winding wires – Part 36: Solderable

polyesterimide enamelled round copper wire, class 180, with a bonding layer

IEC 60317-37, Specifications for particular types of winding wires – Part 37: Polyesterimide

enamelled round copper wire, class 180, with a bonding layer

IEC 60317-38, Specifications for particular types of winding wires – Part 38: Polyester or

polyesterimide overcoated with polyamide-imide enamelled round copper wire, class 200, with

a bonding layer

IEC 60317-42, Specifications for particular types of winding wires – Part 42: Polyester-amide-

imide enamelled round copper wire, class 200

IEC 60317-43, Specifications for particular types of winding wires – Part 43: Aromatic

polyimide tape wrapped round copper wire, class 240

IEC 60317-46, Specifications for particular types of winding wires – Part 46: Aromatic

polyimide enamelled round copper wires, class 240

IEC 60317-48, Specifications for particular types of winding wires – Part 48: Glass-fibre

wound resin or varnish impregnated, bare or enamelled round copper wire, temperature index

155
———————
Withdrawn.
---------------------- Page: 10 ----------------------
61858-1 © IEC:2014 – 9 –

IEC 60317-50, Specifications for particular types of winding wires – Part 50: Glass-fibre

wound silicone resin or varnish impregnated, bare or enamelled round copper wire,

temperature index 200

IEC 60317-51, Specifications for particular types of winding wires – Part 51: Solderable

polyurethane enamelled round copper wire, class 180

IEC 60317-53, Specifications for particular types of winding wires – Part 53: Aromatic

polyamide (aramid) tape wrapped rectangular copper wire, temperature index 220

IEC 60317-54, Specifications for particular types of winding wires – Part 54: Polyester

enamelled round copper wire, class 155 L
(withdrawn)

IEC 60317-55, Specifications for particular types of winding wires – Part 55: Solderable

polyurethane enamelled round copper wire overcoated with polyamide, class 180

IEC 60317-57, Specifications for particular types of winding wires – Part 57: Polyamide-imide

enamelled round copper wire, class 220
IEC 60505, Evaluation and qualification of electrical insulation systems

IEC 61033, Test methods for the determination of bond strength of impregnating agents to an

enamelled wire substrate

IEC 61857 (all parts), Electrical insulation systems – Procedures for thermal evaluation

IEC 61857-1:2008, Electrical insulation systems – Procedures for thermal evaluation – Part 1:

General requirements – Low voltage

IEC 61857-21, Electrical insulation systems – Procedures for thermal evaluation – Part 21:

Specific requirements for general purpose models – Wire-wound applications

IEC 62317-2, Ferrite cores – Dimensions – Part 2: Pot-cores for use in telecommunications,

power supply, and filter applications.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
enamelled winding wire
insulated conductors made in accordance with the IEC 60317 series
3.2
wrapped insulated winding wire

insulated conductor, round or shaped, where the insulation is applied as a tape, with or

without an adhesive, made from a film or a paper and applied to the conductor, made in

accordance with the IEC 60317 series
———————
Withdrawn.
---------------------- Page: 11 ----------------------
– 10 – 61858-1 © IEC:2014
3.3
random wound coils

coils for use in an electrotechnical device made with enamelled winding wire without concern

for the location of the turns
3.4
precision wound coils

coils for use in an electrotechnical device made with enamelled winding wire with each turn

positioned in a specific and successive way
3.5
form wound winding coil
rectangular wire formed to a coil for use in an electrotechnical device

Note 1 to entry: Usually made with an insulated conductor this may be enamelled, fibrous wrapped or enamelled

with fibrous wrapping. Afterwards the coil is wound it receives multiple layers of tape wrapped insulation and is

vacuum- or vacuum-pressure impregnated with a resin, or wrapped with sufficient layers of a pre-impregnated B-

stage tape and processed using resin-rich method.
3.6
wire-wound winding electrical insulation system

EIS evaluated with the wire wound coils that are either random or precision wound; not form

wound coils
3.7
wire-wound winding electrotechnical device
electrotechnical devi
...

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