SIST EN IEC 60034-18-1:2023

Rotating electrical machines - Part 18-1: Functional evaluation of insulation systems - General guidelines

This part of IEC 60034 deals with the general guidelines for functional evaluation of electrical insulation systems, used or proposed to be used in rotating electrical machines within the scope of IEC 60034-1, in order to qualify them.

Drehende elektrische Maschinen - Teil 18-1: Funktionelle Bewertung von Isoliersystemen - Allgemeine Richtlinien

Machines électriques tournantes - Partie 18-1: Evaluation fonctionnelle des systèmes d'isolation - Principes directeurs généraux

L’IEC 60034-18-1:2022 traite des lignes directrices générales pour l'évaluation fonctionnelle des systèmes d'isolation électrique, utilisés ou dont l'utilisation est proposée dans les machines électriques tournantes relevant du domaine d'application de l'IEC 60034-1, en vue de leur qualification. L’IEC 60034-18-1 définit les exigences générales pour la qualification des systèmes d’isolation, dans lesquels, pour le vieillissement thermique, les équations d’Arrhenius ne sont pas nécessairement adaptées, comme cela ressort de nombreux retours d’expérience.
Cette troisième édition annule et remplace la deuxième édition parue en 2010. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a. comme auparavant, fournit des lignes directrices générales pour l'évaluation fonctionnelle de différents types d'enroulements, mais inclut les modifications qui ont été introduites pour la qualification et l'évaluation électriques des enroulements qui subissent une contrainte électrique du fait d'une alimentation par convertisseur;

b. met désormais l'accent sur les lignes directrices générales, tous les détails techniques des procédures et des principes de qualification étant déplacés vers les parties subséquentes;

c. décrit des aspects généraux supplémentaires de l'évaluation et de la qualification fonctionnelles, en particulier la procédure de comparaison entre les systèmes d'isolation candidat et de référence, l'introduction du concept de qualification pour différentes durées de vie en service prévues, ainsi que l'évaluation des changements mineurs de composants ou de processus de fabrication.

Električni rotacijski stroji - 18-1. del: Funkcijsko ocenjevanje izolacijskih sistemov - Splošne smernice

General Information

• Status: Published
• Public Enquiry End Date: 29-Nov-2020
• Publication Date: 12-Mar-2023
• ICS: 29.080.30 - Insulation systems
• ICS: 29.160 - Rotating machinery
• ICS: 29.160.01 - Rotating machinery in general
• Technical Committee: ERS - Rotating machinery
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 02-Feb-2023
• Due Date: 09-Apr-2023
• Completion Date: 13-Mar-2023
• Ref Project: EN IEC 60034-18-1:2023 - Rotating electrical machines - Part 18-1: Functional evaluation of insulation systems - General guidelines

Relations

• Revised: SIST EN 60034-18-1:2011 - Rotating electrical machines - Part 18-1: Functional evaluation of insulation systems - General guidelines (IEC 60034-18-1:2010)
• Effective Date: 22-Oct-2019

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN IEC 60034-18-1:2023
01-april-2023

Električni rotacijski stroji - 18-1. del: Funkcijsko ocenjevanje izolacijskih sistemov

- Splošne smernice

Rotating electrical machines - Part 18-1: Functional evaluation of insulation systems -

General guidelines
Drehende elektrische Maschinen - Teil 18-1: Funktionelle Bewertung von
Isoliersystemen - Allgemeine Richtlinien

Machines électriques tournantes - Partie 18-1: Evaluation fonctionnelle des systèmes

d'isolation - Principes directeurs généraux
Ta slovenski standard je istoveten z: EN IEC 60034-18-1:2023
ICS:
29.080.30 Izolacijski sistemi Insulation systems
29.160.01 Rotacijski stroji na splošno Rotating machinery in
general
SIST EN IEC 60034-18-1:2023 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN IEC 60034-18-1:2023
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SIST EN IEC 60034-18-1:2023
EUROPEAN STANDARD EN IEC 60034-18-1
NORME EUROPÉENNE
EUROPÄISCHE NORM January 2023
ICS 29.160.01 Supersedes EN 60034-18-1:2010
English Version
Rotating electrical machines - Part 18-1: Functional evaluation of
insulation systems - General guidelines
(IEC 60034-18-1:2022)

Machines électriques tournantes - Partie 18-1: Évaluation Drehende elektrische Maschinen - Teil 18-1: Funktionelle

fonctionnelle des systèmes d'isolation - Lignes directrices Bewertung von Isoliersystemen - Allgemeine Richtlinien

générales (IEC 60034-18-1:2022)
(IEC 60034-18-1:2022)

This European Standard was approved by CENELEC on 2023-01-26. CENELEC members are bound to comply with the CEN/CENELEC

Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC

Management Centre or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the

same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,

Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the

Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Türkiye and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2023 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Ref. No. EN IEC 60034-18-1:2023 E
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SIST EN IEC 60034-18-1:2023
EN IEC 60034-18-1:2023 (E)
European foreword

The text of document 2/2113/FDIS, future edition 3 of IEC 60034-18-1, prepared by IEC/TC 2

"Rotating machinery" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC

as EN IEC 60034-18-1:2023.
The following dates are fixed:

• latest date by which the document has to be implemented at national (dop) 2023-10-26

level by publication of an identical national standard or by endorsement

• latest date by which the national standards conflicting with the (dow) 2026-01-26

document have to be withdrawn

This document supersedes EN 60034-18-1:2010 and all of its amendments and corrigenda (if any).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Any feedback and questions on this document should be directed to the users’ national committee. A

complete listing of these bodies can be found on the CENELEC website.
Endorsement notice

The text of the International Standard IEC 60034-18-1:2022 was approved by CENELEC as a

European Standard without any modification.

In the official version, for Bibliography, the following note has to be added for the standard indicated:

IEC 60216 (series) NOTE Approved as EN 60216 (series)
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SIST EN IEC 60034-18-1:2023
EN IEC 60034-18-1:2023 (E)
Annex A
(normative)
Normative references to international publications
with their corresponding European publications

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.

NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod), the

relevant EN/HD applies.

NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available

here: www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60034-1 - Rotating electrical machines - Part 1: EN 60034-1 -
Rating and performance
IEC 60034-18-21 - Rotating electrical machines - Part 18-21: EN 60034-18-21 -
Functional evaluation of insulation systems
- Test procedures for wire-wound windings
- Thermal evaluation and classification
IEC 60034-18-31 - Rotating electrical machines - Part 18-31: EN 60034-18-31 -
Functional evaluation of insulation systems
- Test procedures for form-wound windings
- Thermal evaluation and classification of
insulation systems used in rotating
machines

IEC 60034-18-32 - Rotating electrical machines - Part 18-32: EN IEC 60034-18-32 -

Functional evaluation of insulation systems
(Type II) - Electrical endurance
qualification procedures for form-wound
windings

IEC/TS 60034-18-33 - Rotating electrical machines - Part 18-33: CLC/TS 60034-18-33 -

Functional evaluation of insulation systems
- Test procedures for form-wound windings
- Multifactor evaluation by endurance
under simultaneous thermal and electrical
stresses
IEC 60034-18-34 - Rotating electrical machines - Part 18-34: EN 60034-18-34 -
Functional evaluation of insulation systems
- Test procedures for form-wound windings
- Evaluation of thermomechanical
endurance of insulation systems

Under preparation. Stage at the time of publication: FprEN 60034-1 and FprEN 60034-1/prAA.

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SIST EN IEC 60034-18-1:2023
EN IEC 60034-18-1:2023 (E)

IEC 60034-18-41 2014 Rotating electrical machines - Part 18-41: EN 60034-18-41 2014

Partial discharge free electrical insulation
systems (Type I) used in rotating electrical
machines fed from voltage converters -
Qualification and quality control tests
+ A1 2019 + A1 2019
IEC 60034-18-42 - Rotating electrical machines - Part 18-42: EN 60034-18-42 -
Partial discharge resistant electrical
insulation systems (Type II) used in
rotating electrical machines fed from
voltage converters - Qualification tests
IEC 60034-27-3 - Rotating electrical machines - Part 27-3: EN 60034-27-3 -
Dielectric dissipation factor measurement
on stator winding insulation of rotating
electrical machines
IEC 60085 - Electrical insulation - Thermal evaluation EN 60085 -
and designation
IEC 60493-1 - Guide for the statistical analysis of ageing - -
test data - Part 1: Methods based on mean
values of normally distributed test results
IEC 60505 2011 Evaluation and qualification of electrical EN 60505 2011
insulation systems
IEC 61858-1 2014 Electrical insulation systems - Thermal EN 61858-1 2014
evaluation of modifications to an
established electrical insulation system
(EIS) - Part 1: Wire-wound winding EIS
IEC 61858-2 2014 Electrical insulation systems - Thermal EN 61858-2 2014
evaluation of modifications to an
established electrical insulation system
(EIS) - Part 2: Form-wound EIS
IEC 62539 - Guide for the statistical analysis of - -
electrical insulation breakdown data
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SIST EN IEC 60034-18-1:2023
IEC 60034-18-1
Edition 3.0 2022-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Rotating electrical machines –
Part 18-1: Functional evaluation of insulation systems – General guidelines
Machines électriques tournantes –
Partie 18-1: Évaluation fonctionnelle des systèmes d'isolation – Lignes
directrices générales
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.160.01 ISBN 978-2-8322-6303-7

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
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SIST EN IEC 60034-18-1:2023
– 2 – IEC 60034-18-1:2022 © IEC 2022
CONTENTS

FOREWORD ........................................................................................................................... 3

INTRODUCTION ..................................................................................................................... 5

1 Scope .............................................................................................................................. 6

2 Normative references ...................................................................................................... 6

3 Terms and definitions ...................................................................................................... 7

3.1 General terms ......................................................................................................... 7

3.2 Terms relating to the objects being tested ............................................................... 8

3.3 Terms relating to factors of influence and ageing factors ........................................ 9

3.4 Terms relating to testing and evaluation .................................................................. 9

4 General aspects of functional evaluation ....................................................................... 10

4.1 Introductory remarks ............................................................................................. 10

4.2 Effects of ageing factors ....................................................................................... 11

4.3 Reference/candidate insulation system ................................................................. 11

4.4 Evaluation of minor changes by components, manufacturing or design ................. 11

4.5 Functional tests .................................................................................................... 12

4.6 Acceptance tests .................................................................................................. 13

5 Thermal functional tests ................................................................................................ 13

5.1 General aspects of thermal functional tests ........................................................... 13

5.2 Analysis, reporting and classification .................................................................... 14

6 Electrical functional tests ............................................................................................... 15

6.1 General aspects of electrical functional tests ........................................................ 15

6.2 Analysis and reporting .......................................................................................... 15

7 Mechanical functional tests ............................................................................................ 16

8 Environmental functional tests ....................................................................................... 16

9 Multifactor functional tests ............................................................................................. 16

Bibliography .......................................................................................................................... 18

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SIST EN IEC 60034-18-1:2023
IEC 60034-18-1:2022 © IEC 2022 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ROTATING ELECTRICAL MACHINES –
Part 18-1: Functional evaluation of insulation systems –
General guidelines
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, Technical Reports,

Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). 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. 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 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 IEC National Committees.

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

Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

misinterpretation by any end user.

4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

transparently to the maximum extent possible in their national and regional publications. Any divergence between

any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.

5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

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

7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

members of its technical committees and IEC National Committees for any personal injury, property damage or

other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

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.

IEC 60034-18-1 has been prepared by IEC technical committee 2: Rotating machinery. It is an

International Standard.

This third edition cancels and replaces the second edition published in 2010. This edition

constitutes a technical revision.

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

edition:

a) provides general guidelines for functional evaluation of different types of windings as before

but incorporates those changes, which have been introduced for the electrical qualification

and evaluation of windings which are electrically stressed by converter-supply;

b) is now focused on general guidelines with all technical details of procedures and

qualification principles moved to the subsequent parts;
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SIST EN IEC 60034-18-1:2023
– 4 – IEC 60034-18-1:2022 © IEC 2022

c) details additional general aspects of functional evaluation and qualification, particularly the

procedure for comparison between reference and candidate insulation systems, the

introduction of the concept of qualification for different expected life-times in service and

the evaluation of minor component or manufacturing changes.
The text of this International Standard is based on the following documents:
Draft Report on voting
2/2113/FDIS 2/2118/RVD

Full information on the voting for its approval can be found in the report on voting indicated in

the above table.
The language used for the development of this International Standard is English.

This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in

accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available

at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are

described in greater detail at www.iec.ch/standardsdev/publications.

A list of all parts in the IEC 60034 series, published under the general title Rotating electrical

machines, 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 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.
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SIST EN IEC 60034-18-1:2023
IEC 60034-18-1:2022 © IEC 2022 – 5 –
INTRODUCTION

IEC 60034-18 comprises several parts, dealing with different types of functional evaluation and

special kinds of test procedures for insulation systems of rotating electrical machines.

IEC 60034-18-1 provides general guidelines for such procedures and qualification principles,

whereas the subsequent parts IEC 60034-18-21, IEC 60034-18-31, IEC 60034-18-32,

IEC TS 60034-18-33, IEC 60034-18-34, IEC 60034-18-41 and IEC 60034-18-42 give detailed

procedures for the various types of windings. Beyond that, part IEC 60034-18-41 and

IEC 60034-18-42 contain special test procedures for electrical evaluation of windings

electrically stressed by converter-supply.

The following standards provide the basis and background for the development of the afore

mentioned standards.

IEC 60505 establishes the basis for estimating the ageing of electrical insulation systems under

conditions of either electrical, thermal, mechanical, environmental stresses or combinations of

these (multifactor stresses). It specifies the general principles and procedures that should be

followed defining functional test and evaluation procedures.

The IEC 60216 series deals with the determination of thermal endurance properties of single

insulating materials. On the assumption, that the Arrhenius formulas describe the rate of

thermal ageing of the materials, test procedures and analyzing instructions for getting

characteristic parameters like the “Temperature index” (TI), the “Halving interval” (HIC) and the

“Relative thermal endurance index” (RTE) are given. For all these parameters selected

properties and accepted end-point-criteria are specified. Consequently, a material may be

assigned with more than one temperature index, derived from the measurement of different

properties and the use of different end-point criteria.

IEC 60034-18-1 defines general requirements on the qualification of insulation systems, where

– for thermal ageing – the Arrhenius equations do not necessarily fit, according to many

experiences.

IEC 60085 deals with thermal evaluation of electrical insulation materials and in particular

insulation systems used in electrical equipment. In particular, thermal classes of insulation

systems are defined and designations are given, such as 130 (B), 155 (F) and 180 (H) for use

in rotating machines belonging to IEC 60034-1. In the past, materials for insulation systems

were often selected solely on the basis of thermal endurance of individual materials performed

according to the IEC 60216 series. However, IEC 60085 recognizes that such selection may

be used only for screening materials prior to further functional evaluation of a new insulation

system which is not service-proven. Evaluation is performed on the basis of a comparison with

a service-proven reference insulation system. Service experience is the preferred basis for

assessing the thermal endurance of an insulation system.

IEC 62539 defines statistical methods to analyse times to breakdown and breakdown voltage

data obtained from electrical testing of solid insulation materials, for the purposes of

characterization of the system and comparison with other insulation systems. The methods of

analysis are described for the Weibull-distribution, but other distributions are also presented.

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SIST EN IEC 60034-18-1:2023
– 6 – IEC 60034-18-1:2022 © IEC 2022
ROTATING ELECTRICAL MACHINES –
Part 18-1: Functional evaluation of insulation systems –
General guidelines
1 Scope

This part of IEC 60034 deals with the general guidelines for functional evaluation of electrical

insulation systems, used or proposed to be used in rotating electrical machines within the scope

of IEC 60034-1, in order to qualify them.
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 60034-1, Rotating electrical machines – Part 1: Rating and performance

IEC 60034-18-21, Rotating electrical machines – Part 18-21: Functional evaluation of insulation

systems – Test procedures for wire-wound windings – Thermal evaluation and classification

IEC 60034-18-31, Rotating electrical machines – Part 18-31: Functional evaluation of insulation

systems – Test procedures for form-wound windings – Thermal evaluation and classification of

insulation systems used in rotating machines

IEC 60034-18-32, Rotating electrical machines – Part 18-32: Functional evaluation of insulation

systems (Type II) – Electrical endurance qualification procedures for form-wound windings

IEC TS 60034-18-33, Rotating electrical machines – Part 18-33: Functional evaluation of

insulation systems – Test procedures for form-wound windings – Multifactor evaluation by

endurance under simultaneous thermal and electrical stresses

IEC 60034-18-34, Rotating electrical machines – Part 18-34: Functional evaluation of insulation

systems – Test procedures for form-wound windings – Evaluation of thermomechanical

endurance of insulation systems

IEC 60034-18-41:2014, Rotating electrical machines – Part 18-41: Partial discharge free

electrical insulation systems (Type I) used in rotating electrical machines fed from voltage

converters – Qualification and quality control tests
IEC 60034-18-41:2014/AMD1:2019

IEC 60034-18-42, Rotating electrical machines – Part 18-42: Partial discharge resistant

electrical insulation systems (Type II) used in rotating electrical machines fed from voltage

converters – Qualification tests

IEC 60034-27-3, Rotating electrical machines – Part 27-3: Dielectric dissipation factor

measurement on stator winding insulation of rotating electrical machines
IEC 60085, Electrical insulation – Thermal evaluation and designation
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SIST EN IEC 60034-18-1:2023
IEC 60034-18-1:2022 © IEC 2022 – 7 –

IEC 60493-1, Guide for the statistical analysis of ageing test data – Part 1: Methods based on

mean values of normally distributed test results
IEC 60505:2011, Evaluation and qualification of electrical insulation systems

IEC 61858-1:2014, Electrical insulation systems – Thermal evaluation of modifications to an

established electrical insulation system (EIS) – Part 1: Wire-wound winding EIS

IEC 61858-2:2014, Electrical insulation systems – Thermal evaluation of modifications to an

established electrical insulation system (EIS) – Part 2: Form-wound EIS

IEC 62539, Guide for the statistical analysis of electrical insulation breakdown data

3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
3.1 General terms
3.1.1
class temperature

temperature for which the insulation system is suitable, as defined by the thermal class in

and as used in IEC 60505
IEC 60085
3.1.2
electrical insulation system
EIS

insulating structure containing one or more electrical insulating materials (EIM) together with

associated conducting parts employed in an electrotechnical device
[SOURCE: IEC 60505:2011, 3.1.1]
3.1.3
candidate insulation system

insulation system being tested to determine its capability with respect to ageing factors

[SOURCE: IEC 60050-411:1996, 411-39-26]
3.1.4
reference insulation system

insulation system whose performance has been established by satisfactory service experience

[SOURCE: IEC 60050-411:1996, 411-39-27]
3.1.5
coil

one or more turns of insulated conductors connected in series and surrounded by common

insulation, arranged to link or produce magnetic flux
[SOURCE: IEC 60050-411:1996, 411-38-03]
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SIST EN IEC 60034-18-1:2023
– 8 – IEC 60034-18-1:2022 © IEC 2022
3.1.6
bar

either of two parts which, after placed in their slots and when connected together, will form the

complete form-wound coil (see 3.1.8) and which comprise a coil side and an appropriate end

winding

Note 1 to entry: Large AC machines commonly use bars, and usually, though not always, they form single-turn coils

in a two-layer winding.
[SOURCE: IEC 60050-411:1996, 411-38-05]
3.1.7
wire-wound winding

winding which is wound with one or several insulated conductors and in which the individual

conductors occupy random positions in the coil side
Note 1 to entry: It is usually random-wound with round conductors.
[SOURCE: IEC 60050-411:1996, 411-38-13]
3.1.8
form-wound winding

winding consisting of coils or bars which are preformed to shape, insulated and substantially

completed before they are inserted into their final places
Note 1 to entry: Coils or bars are usually wound with rectangular conductors.
[SOURCE: IEC 60050-411:1996, 411-38-11]
3.2 Terms relating to the objects being tested
3.2.1
test object
unit being tested

Note 1 to entry: It may be an actual machine or part thereof or a special test model (see 3.2.3 and 3.2.4) which can

be subjected to functional tests.

Note 2 to entry: A test object may contain more than one test specimen (see 3.2.2).

3.2.2
test specimen

individual component within a test object which can be used to generate one piece of test data

(e.g. time to failure)

Note 1 to entry: A test specimen may contain more than one insulation component (e.g. turn insulation and

conductor to earth insulation), any one of which can provide that piece of data.
3.2.3
formette

special test model used for the evaluation of the insulation systems for form-wound windings

[SOURCE: IEC 60050-411:1996, 411-53-64]
3.2.4
motorette

special test model used for the evaluation of the insulation systems for wire-wound (random-

wound) windings
[SOURCE: IEC 60050-411:1996, 411-53-65]
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SIST EN IEC 60034-18-1:2023
IEC 60034-18-1:2022 © IEC 2022 – 9 –
3.3 Terms relating to factors of influence and ageing factors
3.3.1
factor of influence

stress imposed by conditions of operation, environment or test that may affect ageing or life of

an insulation system
3.3.2
ageing factor
factor of influence that causes ageing

Note 1 to entry: In the winding of an electrical machine, different factors of influence or ageing factors can be

dominant in different parts (e.g. turn insulation and end-winding insulation). Therefore, different criteria may be used

to assess those parts of the insulation. It can also be appropriate to apply different procedures of functional evaluation

to these parts.
3.4 Terms relating to testing and evaluation
3.4.1
diagnostic factor

variable or fixed stress which is applied to an EIS to establish the degree of ageing

[SOURCE: IEC 60505:2011, 3.3.7]
...

SLOVENSKI STANDARD
oSIST prEN 60034-18-1:2020
01-november-2020

Električni rotacijski stroji - 18-1. del: Funkcijsko ocenjevanje izolacijskih sistemov

- Splošne smernice

Rotating electrical machines - Part 18-1: Functional evaluation of insulation systems -

General guidelines
Drehende elektrische Maschinen - Teil 18-1: Funktionelle Bewertung von
Isoliersystemen - Allgemeine Richtlinien

Machines électriques tournantes - Partie 18-1: Evaluation fonctionnelle des systèmes

d'isolation - Principes directeurs généraux
Ta slovenski standard je istoveten z: prEN IEC 60034-18-1:2020
ICS:
29.080.30 Izolacijski sistemi Insulation systems
29.160.01 Rotacijski stroji na splošno Rotating machinery in
general
oSIST prEN 60034-18-1:2020 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 60034-18-1:2020
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oSIST prEN 60034-18-1:2020
2/2015/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 60034-18-1 ED3
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2020-09-11 2020-12-04
SUPERSEDES DOCUMENTS:
2/1970/CD, 2/1980A/CC
IEC TC 2 : ROTATING MACHINERY
SECRETARIAT: SECRETARY:
United Kingdom Mr Charles Whitlock
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:
Other TC/SCs are requested to indicate their interest, if any, in
this CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY

SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING

Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft for Vote
(CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.

This document is still under study and subject to change. It should not be used for reference purposes.

Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of which they are

aware and to provide supporting documentation.
TITLE:

Rotating electrical machines – Part 18-1: Functional evaluation of insulation systems – General guidelines

PROPOSED STABILITY DATE: 2024
NOTE FROM TC/SC OFFICERS:

Copyright © 2020 International Electrotechnical Commission, IEC. All rights reserved. It is permitted to download this

electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.

You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other purpose without

permission in writing from IEC.
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CONTENTS

FOREWORD ........................................................................................................................... 3

INTRODUCTION ..................................................................................................................... 5

1 Scope ............................................................................................................................... 6

2 Normative references ....................................................................................................... 6

3 Terms and definitions ....................................................................................................... 7

3.1 General terms ......................................................................................................... 7

3.2 Terms relating to the objects being tested ............................................................... 8

3.3 Terms relating to factors of influence and ageing factors ......................................... 8

3.4 Terms relating to testing and evaluation .................................................................. 9

4 General aspects of functional evaluation ........................................................................ 10

4.1 Introductory remarks ............................................................................................. 10

4.2 Effects of ageing factors ........................................................................................ 10

4.3 Reference/candidate insulation system .................................................................. 11

4.4 Evaluation of minor component or manufacturing changes .................................... 11

4.5 Functional tests ..................................................................................................... 12

4.6 Acceptance tests ................................................................................................... 12

5 Thermal functional tests ................................................................................................. 13

5.1 General aspects of thermal functional tests ........................................................... 13

5.2 Analysis, reporting and classification ..................................................................... 13

6 Electrical functional tests ................................................................................................ 14

6.1 General aspects of electrical functional tests ......................................................... 14

6.2 Analysis and reporting .......................................................................................... 15

7 Mechanical functional tests............................................................................................. 15

8 Environmental functional tests ........................................................................................ 15

9 Multifactor functional tests .............................................................................................. 16

Bibliography .......................................................................................................................... 17

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oSIST prEN 60034-18-1:2020
IEC CDV 60034-18-1  IEC 2020 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ROTATING ELECTRICAL MACHINES –
Part 18-1: Functional evaluation of insulation systems –
General guidelines
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 interna-

tional co-operation on all questions concerning standardization in the electrical and electronic fields. To this

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organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the Interna-

tional 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 inter-

ested IEC National Committees.

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

Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

transparently to the maximum extent possible in their national and regional publications. Any divergence be-

tween any IEC Publication and the corresponding national or regional publication shall be clearly indicated in

the latter.

5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

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

7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

members of its technical committees and IEC National Committees for any personal injury, property damage or

other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and ex-

penses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publica-

tions.

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 pa-

tent rights. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 60034-18-1 has been prepared by IEC technical committee 2:

Rotating machinery.

This third edition cancels and replaces the second edition, published in 2010 , and constitutes

a technical revision.

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

edition:

– provides general guidelines for functional evaluation of different types of windings as be-

fore but incorporates those changes, which have been introduced for the electrical qualifi-

cation and evaluation of windings which are electrically stressed by converter-supply;

– is now focused on general guidelines with all technical details of procedures and qualifica-

tion principles moved to the subsequent parts;

– details additional general aspects of functional evaluation and qualification, particularly

the procedure for comparison between reference and candidate insulation systems, the in-

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troduction of the concept of qualification for different expected lifetimes in service and the

evaluation of minor component or manufacturing changes;
The text of this standard is based on IEC 60034-18-1:2010

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.

NOTE A list of cross-references of all IEC TC 2 publications can be found in the IEC TC 2 dashboard on the IEC

website.

The committee has decided that the contents of this edition 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.
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IEC CDV 60034-18-1  IEC 2020 – 5 –
1 INTRODUCTION

2 IEC 60034-18 comprises several parts, dealing with different types of functional evaluation

3 and special kinds of test procedures for insulation systems of rotating electrical machines.

4 IEC 60034-18-1 provides general guidelines for such procedures and qualification principles,

5 whereas the subsequent parts IEC 60034-18-21, IEC 60034-18-31, IEC 60034-18-32,

6 IEC 60034-18-33, IEC 60034-18-34, IEC 60034-18-41 and IEC 60034-18-42 give detailed

7 procedures for the various types of windings. Beyond that, part IEC 60034-18-41 and

8 IEC 60034-18-42 contain special test procedures for electrical evaluation of windings

9 electrically stressed by converter-supply.

10 The following standards provide the basis and background for the development of the

11 previous standards:

12 IEC 60505 establishes the basis for estimating the ageing of electrical insulation systems

13 under conditions of either electrical, thermal, mechanical, environmental stresses or

14 combinations of these (multifactor stresses). It specifies the general principles and

15 procedures that should be followed defining functional test and evaluation procedures.

16 The IEC 60216 series deals with the determination of thermal endurance properties of single

17 insulating materials. On the assumption, that the Arrhenius equations describe the rate of

18 thermal ageing, test procedures and analyzing instructions for getting characteristic

19 parameters like the “Temperature index” (TI), the “Halving interval” (HIC) and the “Relative

20 thermal endurance index” (RTE) are given. For all these parameters selected properties and

21 accepted end-point-criteria are specified. Consequently, a material may be assigned with

22 more than one temperature index, derived from the measurement of different properties and

23 the use of different end-point criteria.IEC 60085 deals with thermal evaluation of electrical in-

24 sulation materials and in particular insulation systems used in electrical equipment …”. In par-

25 ticular, thermal classes of insulation systems are defined and designations are given, such as

26 130 (B), 155 (F) and 180 (H) for use in rotating machines belonging to IEC 60034-1. In the

27 past, materials for insulation systems were often selected solely on the basis of thermal en-

28 durance of individual materials performed according to the IEC 60216 series. However,

29 IEC 60085 recognizes that such selection may be used only for screening materials prior to

30 further functional evaluation of a new insulation system which is not service-proven. Evalua-

31 tion is performed on the basis of a comparison with a service-proven reference insulation sys-

32 tem. Service experience is the preferred basis for assessing the thermal endurance of an in-

33 sulation system.

34 IEC 62539 defines statistical methods to analyse times to breakdown and breakdown voltage

35 data obtained from electrical testing of solid insulation materials, for the purposes of

36 characterization of the system and comparison with other insulation systems. The methods of

37 analysis are described for the Weibull-distribution but other distributions are also presented.

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39 ROTATING ELECTRICAL MACHINES –
41 Part 18-1: Functional evaluation of insulation systems –
42 General guidelines
44 1 Scope

45 This part of IEC 60034 deals with the general guidelines for functional evaluation of electrical

46 insulation systems, used or proposed to be used in rotating electrical machines within the

47 scope of IEC 60034-1, in order to qualify them.
48 2 Normative references

49 The following referenced documents are indispensable for the application of this document.

50 For dated references, only the edition cited applies. For undated references, the latest edition

51 of the referenced document (including any amendments) applies.
52 IEC 60034-1, Rotating electrical machines – Part 1: Rating and performance

53 IEC 60034-18-21, Rotating electrical machines – Part 18-21: Functional evaluation of insula-

54 tion systems – Test procedures for wire-wound windings – Thermal evaluation and classifica-

55 tion

56 IEC 60034-18-31, Rotating electrical machines – Part 18-31: Functional evaluation of insula-

57 tion systems – Test procedures for form-wound windings – Thermal evaluation and classifica-

58 tion of insulation systems used in machines up to and including 50 MVA and 15 kV

59 IEC 60034-18-32, Rotating electrical machines – Part 18-32: Functional evaluation of insula-

60 tion systems – Test procedures for form-wound windings – Evaluation of electrical endurance

61 of insulation systems used in machines up to and including 50 MVA and 15 kV

62 IEC 60034-18-33, Rotating electrical machines – Part 18-33: Functional evaluation of insula-

63 tion systems – Test procedures for form-wound windings – Multifactor functional evaluation –

64 Endurance under combined thermal and electrical stresses of insulation systems used in ma-

65 chines up to and including 50 MVA and 15 kV

66 IEC 60034-18-34, Rotating electrical machines – Part 18-34: Functional evaluation of insula-

67 tion systems – Test procedures for form-wound windings – Evaluation of thermomechanical

68 endurance of insulation systems

69 IEC 60034-18-41 EDITION 1.1, Rotating electrical machines – Part 18-41: Partial discharge free

70 electrical insulation systems (Type I) used in rotating electrical machines fed from voltage converters -

71 Qualification and quality control tests / Combines IEC 60034-18-41 (2014-03) and AMD 1 (2019-06)

72 IEC 60034-18-42, Rotating electrical machines – Part 18-42: Partial discharge resistant electrical

73 insulation systems (Type II) used in rotating electrical machines fed from voltage converters - Qualifica-

74 tion tests IEC 60085, Thermal evaluation and designation of electrical insulation

75 IEC 60216 (all parts), Electrical insulating materials – Properties of thermal endurance

76 IEC 60493-1, Guide for the statistical analysis of ageing test data – Part 1: Methods based on

77 mean values of normally distributed test results
78 IEC 60505:2004, Evaluation and qualification of electrical insulation systems

79 IEC 61858-1 (2014-02-01, valid) Electrical insulation systems - Thermal evaluation of

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80 modifications to an established EIS - Part 1: Wire-wound winding EIS

81 IEC 61858-2 (2014-02-01,valid) Electrical insulation systems - Thermal evaluation of

82 modifications to an established EIS - Part 2: Form-wound EIS

83 IEC 62539, Guide for the statistical analysis of electrical insulation breakdown data

84 3 Terms and definitions
85 For the purposes of this document, the following terms and definitions apply.
86 3.1 General terms
87 3.1.1
88 class temperature

89 temperature for which the insulation system is suitable, as defined by the thermal class in

90 IEC 60085 and as used in IEC 60505
91 3.1.2
92 insulation system

93 insulating structure containing one or more electrical insulating materials applied over con-

94 ducting parts employed in rotating electrical machines
95 [IEC 60505:2004, 3.1.1, modified]

96 NOTE 1 There may be several insulation components within the windings, each being designed for different

97 stresses in service, i.e. turn insulation, slot insulation and end-winding insulation. Different criteria may be applied

98 to the various components within the overall system.

99 NOTE 2 There may be more than one insulation system in a particular type of machine. These insulation systems

100 may have different thermal classes (e.g. stator and rotor windings).
101 3.1.3
102 candidate insulation system

103 insulation system being tested to determine its capability with respect to ageing factors

104 [IEC 60050-411, Amendment 1:2007, 411-39-26, modified]
105 3.1.4
106 reference insulation system

107 insulation system whose performance has been established by satisfactory service

108 experience
109 [IEC 60050-411, Amendment 1:2007, 411-39-27]
110 3.1.5
111 coil

112 one or more turns of insulated conductors connected in series and surrounded by common

113 insulation, arranged to link or produce magnetic flux
114 [IEC 60050-411:1996, 411-38-03, modified]
115 3.1.6
116 bar

117 either of two parts which, after placed in their slots and when connected together, will form

118 the complete form-wound coil (see 3.1.8) and which comprise a coil side and an appropriate

119 end winding
120 [IEC 60050-411:1996, 411-38-05, modified]
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121 NOTE Large a.c. machines commonly use bars, and usually, though not always, they form single-turn coils in a

122 two-layer winding.
123 3.1.7
124 wire-wound winding

125 winding which is wound with one or several insulated conductors and in which the individual

126 conductors occupy random positions in the coil side
127 NOTE It is usually random-wound with round conductors.
128 [IEC 60050-411:1996, 411-38-13, modified]
129 3.1.8
130 form-wound winding

131 winding consisting of coils or bars which are preformed to shape, insulated and substantially

132 completed before they are inserted into their final places
133 NOTE Coils or bars are usually wound with rectangular conductors.
134 [IEC 60050-411:1996, 411-38-11, modified]
135 3.2 Terms relating to the objects being tested
136 3.2.1
137 test object
138 unit being tested

139 NOTE 1 It may be an actual machine or part thereof or a special test model (see 3.2.3 and 3.2.4) which can be

140 subjected to functional tests.
141 NOTE 2 A test object may contain more than one test specimen (see 3.2.2).
142 3.2.2
143 test specimen

144 individual component within a test object which can be used to generate one piece of test da-

145 ta (e.g. time to failure)

146 NOTE A test specimen may contain more than one insulation component (e.g. turn insulation and conductor to

147 earth insulation), any one of which can provide that piece of data.
148 3.2.3
149 formette

150 special test model used for the evaluation of the insulation systems for form-wound windings

151 [IEC 60050-411, Amendment 1:2007, 411-53-64]
152 3.2.4
153 motorette

154 special test model used for the evaluation of the insulation systems for wire-wound (random-

155 wound) windings
156 [IEC 60050-411, Amendment 1:2007, 411-53-65]
157 3.3 Terms relating to factors of influence and ageing factors
158 3.3.1
159 factor of influence

160 stress imposed by conditions of operation, environment or test that may affect ageing or life of

161 an insulation system
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162 3.3.2
163 ageing factor
164 factor of influence that causes ageing

165 NOTE In the winding of an electrical machine, different factors of influence or ageing factors can be dominant in

166 different parts (e.g. turn insulation and end-winding insulation). Therefore, different criteria may be used to assess

167 those parts of the insulation. It can also be appropriate to apply different procedures of functional evaluation to

168 these parts.
169 3.4 Terms relating to testing and evaluation
170 3.4.1
171 diagnostic factor

172 variable or fixed stress applied to an insulation component of a test specimen in order to es-

173 tablish its condition after ageing without significantly adding to the ageing

174 [IEC 60505:2004, 3.3.7, modified]
175 3.4.2
176 functional test

177 comparative test in which the candidate and the reference insulation systems are exposed to

178 ageing and diagnostic factors in order to qualify the candidate system, or, a functional test

179 may also be related to a diagnostic property, for instance as defined in IEC 60034-18-41, the

180 PD-inception voltage.
181 3.4.3
182 endurance test

183 test in which the insulation system of a test object is exposed to one or more ageing factors

184 related to service conditions and where changes in specific properties are evaluated by

185 diagnostic tests
186 3.4.4
187 diagnostic test

188 test in which the insulation system of a test object is exposed to one or more diagnostic

189 factors in order to discern its condition through measurements or proof tests and to determine

190 when the end-point criterion has been reached
191 3.4.5
192 end-point criterion

193 selected value of a characteristic of a test object indicating the end of its test life or arbitrarily

194 chosen for the purpose of the comparison of insulation systems
195 3.4.6
196 end-point
197 end of a test as defined by the end-point criterion
198 3.4.7
199 classification

200 set of actions leading to determination of the thermal class of an insulation system

201
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202 3.4.8
203 type test

204 It is conducted on first prototype of product to confirm the design specifications, it is usually

205 not repeated on other products of same type.
206 3.4.9
207 quality control test

208 are followed in order to ensure that the quality of a product is maintained against a set of

209 benchmarks and that any errors encountered are either eliminated or reduced.
210
211 3.4.10
212 routine test

213 A test made on each individual device during or after manufacture to check, if it complies with

214 the requirements of the standard concerned or the criteria specified.
215 4 General aspects of functional evaluation
216 4.1 Introductory remarks

217 Most functional tests given in the IEC 60034-18 series are comparative. The performance of a

218 candidate system is compared with that of a reference system when both are subjected to

219 equivalent test conditions with respect to test objects, methods of ageing and diagnostic tests.

220 It is not necessarily required that the reference system is physically to be tested in parallel, if

221 the test results of the reference system used have been documented previously and obtained

222 from same test conditions.

223 The reference system normally is particular and real – but its quantified minimum performance

224 can also be defined by an agreed reference lifeline, provided by an IEC-Standard as in

225 60034-18-42.

226 At the end of every functional test, the functional evaluation shall be made. This means it is

227 necessary to compare the diagnostic data obtained from the candidate and the reference

228 system, usually to compare the mean times to failure.

229 If the data from the candidate system is no worse than from the reference system, the

230 candidate system is considered to be qualified. This is true if the 90 % confidence interval of

231 that percentile of the used probability distribution which represents the mean value falls above

232 or within that obtained from the reference system (see IEC 60493-1 and IEC 62539).

233 The large differences found in rotating electrical machine windings, in terms of size, voltage,

234 operating conditions and expected lifetime-behaviour during service necessitate the use of

235 different procedures for functional evaluation of thermal, electrical and multifactor ageing (se-

236 ries 18-21, -31, -32, -33, -34, -41, -42) to qualify various types of windings. These procedures

237 can be of different complexity, the simplest being based on a single ageing factor (e.g. ther-

238 mal or electrical).

239 The procedures for functional evaluation will permit comparisons and allow qualification of

240 candidate insulation systems. However, they cannot completely determine the merits of any

241 particular insulation system. Principally it is not possible to give an operational lifetime fore-

242 cast of the individual winding insulation based on any kind of functional tests. Such

243 information can be obtained in general only from extended service experience.

244 4.2 Effects of ageing factors

245 All ageing factors, i.e. thermal, electrical, environmental and mechanical, affect the life of all

246 types of machines but the significance of each factor varies with the type of machine and the

247 expected duty. In some cases, one of these ageing factors is considered to be dominant.

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248 In other cases, several ageing factors may be acting significantly. These different conditions

249 have to be considered in choosing the appropriate functional test according to this standard.

250 Insulation of small or medium low-voltage line-fed machines is degraded primarily by

251 temperature and environment, with electrical and mechanical stresses being of less

252 importance.

253 Medium to large machines, using form-wound windings, are also affected by temperature and

254 environment but, in addition, the electrical and mechanical stresses can be important ageing

255 factors.

256 Very large machines, which generally utilize form-wound (with bars) windings and which can

257 operate in a special environment such as hydrogen, are normally most affected by mechanical

258 stresses or electrical stresses, or both. Temperature and environment can be less significant

259 ageing factors.

260 The winding insulation system of small, medium, large and very large converter fed machines

261 may be substantially electrically stressed (see IEC 60034-18-41 and IEC 60034-18-42).

262 4.3 Reference/candidate insulation system

263 An insulation system qualifies to be used as a reference insulation system if its performance

264 has been established by satisfactory service experience. This means:

265 – it has shown successful operation over suitably long periods of time at operating

266 conditions characteristic of the rating (or class) and in typic
...