SIST EN 61858:2005

SLOVENSKI SIST EN 61858:2005

STANDARD
julij 2005
Sistemi električne izolacije – Toplotno vrednotenje sprememb preverjenega
EIS z žičnim navitjem
Electrical insulation systems – Thermal evaluation of modifications to an established
wire-wound EIS
ICS 29.080.30 Referenčna številka
SIST EN 61858:2005(en)
©  Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno

---------------------- Page: 1 ----------------------

EUROPEAN STANDARD EN 61858
NORME EUROPÉENNE
EUROPÄISCHE NORM March 2005

ICS 29.080.30 Supersedes EN 61858:2000


English version


Electrical insulation systems –
Thermal evaluation of modifications to an established wire-wound EIS
(IEC 61858:2004)


Systèmes d'isolation électrique - Elektrische Isoliersysteme –
Evaluation thermique des modifications Thermische Bewertung von
apportées à un système d'isolation Veränderungen an einem erprobten,
électrique éprouvé à enroulements à fil drahtgewickelten EIS
(CEI 61858:2004) (IEC 61858:2004)



This European Standard was approved by CENELEC on 2005-02-01. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden,
Switzerland and United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: rue de Stassart 35, B - 1050 Brussels


© 2005 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 61858:2005 E

---------------------- Page: 2 ----------------------

EN 61858:2005 - 2 -
Foreword
The text of document 98/221/FDIS, future edition 2 of IEC 61858, prepared by IEC TC 98, Electrical
insulation systems (EIS), was submitted to the IEC-CENELEC parallel vote and was approved by
CENELEC as EN 61858 on 2005-02-01.
This European Standard supersedes EN 61858:2000.
It constitutes a technical revision that incorporates test procedures referenced in EN 60034-18-22.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2005-11-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2008-02-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 61858:2004 was approved by CENELEC as a European
Standard without any modification.
__________

---------------------- Page: 3 ----------------------

- 3 - EN 61858:2005
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications
The following referenced documents are indispensable for the application 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 Where an international publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
Publication Year Title EN/HD Year
1) 2)
IEC 60172 - Test procedure for the determination of EN 60172 1994
the temperature index of enamelled
winding wires

1) 2)
IEC 60216-5 - Electrical insulating materials - Thermal EN 60216-5 2003
endurance properties
Part 5: Determination of relative thermal
endurance index (RTE) of an insulating
material

IEC 60317 Series Specifications for particular types of EN 60317 Series
winding wires

1) 2)
IEC 60505 - Evaluation and qualification of electrical EN 60505 2004
insulation systems

1)
IEC 60791 - Performance evaluation of insulation - -
systems based on service experience and
functional tests

1)
IEC 61033 - Test methods for the determination of - -
bond strength of impregnating agents to
an enamelled wire substrate

IEC 61857 Series Electrical insulation systems - Procedures EN 61857 Series
for thermal evaluation

1) 2)
IEC 61857-1 - Electrical insulation systems - Procedures EN 61857-1 2005
for thermal evaluation
Part 1: General requirements - Low-
voltage

1) 2)
IEC 62114 - Electrical insulation systems (EIS) - EN 62114 2001
Thermal classification




1)
Undated reference.
2)
Valid edition at date of issue.

---------------------- Page: 4 ----------------------

NORME CEI
INTERNATIONALE IEC
61858
INTERNATIONAL
Deuxième édition
STANDARD
Second edition
2004-11
Systèmes d'isolation électrique –
Evaluation thermique des modifications apportées
à un système d'isolation électrique éprouvé
à enroulements à fil
Electrical insulation systems –
Thermal evaluation of modifications to
an established wire-wound EIS
© IEC 2004 Droits de reproduction réservés ⎯ Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in any
utilisée sous quelque forme que ce soit et par aucun procédé, form or by any means, electronic or mechanical, including
électronique ou mécanique, y compris la photocopie et les photocopying and microfilm, without permission in writing from
microfilms, sans l'accord écrit de l'éditeur. the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
CODE PRIX
PRICE CODE Q
Commission Electrotechnique Internationale
International Electrotechnical Commission
ɆɟɠɞɭɧɚɪɨɞɧɚɹɗɥɟɤɬɪɨɬɟɯɧɢɱɟɫɤɚɹɄɨɦɢɫɫɢɹ
Pour prix, voir catalogue en vigueur
For price, see current catalogue

---------------------- Page: 5 ----------------------

61858 © IEC:2004 – 3 –
CONTENTS
FOREWORD.5
INTRODUCTION.9
1 Scope.11
2 Normative references .11
3 Terms and definitions .13
4 General considerations.13
5 Evaluation of the change of thickness of an EIM.17
5.1 Samples .17
5.2 Acceptance .17
6 Substitution of winding wire .17
6.1 General .17
6.2 Substitution of enamel.17
6.3 Substitution of conductor material .17
6.4 Alternate winding wire .19
7 Substitution of impregnating resin/varnish .19
7.1 Thermal class determination.19
7.2 Evaluation .19
8 Substitution with other EIM.21
8.1 Technically equivalent materials.21
8.2 Previous evaluation .21
8.3 Other.21
9 Evaluation of additions .21
9.1 Addition of an impregnating resin/varnish .21
9.2 Addition of other components .23
10 Single-point thermal ageing test .23
10.1 Test objects.23
10.2 Establishing the relative thermal endurance index (RTE).23
10.3 Interpretation of results .25
Annex A (normative) Classes of winding wire.27
Annex B (normative) Compatibility test procedure.29
Figure 1 – Overview of evaluation methods.15
Table 1 – Thermal ageing test methods for resin/varnishes.19
Table A.1 – Winding wire types.27

---------------------- Page: 6 ----------------------

61858 © IEC:2004 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL INSULATION SYSTEMS –
THERMAL EVALUATION OF MODIFICATIONS TO
AN ESTABLISHED WIRE-WOUND 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,
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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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.
International Standard IEC 61858 has been prepared by IEC technical committee 98:
Electrical insulation systems (EIS).
This second edition cancels and replaces the first edition, published in 1999, and constitutes
a technical revision that incorporates test procedures referenced in IEC 60034-18-22.
The text of this standard is based on the following documents:
FDIS Report on voting
98/221/FDIS 98/227/RVD
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.

---------------------- Page: 7 ----------------------

61858 © IEC:2004 – 7 –
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result 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.
.

---------------------- Page: 8 ----------------------

61858 © IEC:2004 – 9 –
INTRODUCTION
This International Standard describes procedures for the evaluation of changes to an
established electrical insulation system (EIS) for wire-wound electrotechnical devices and the
effect of these changes on the thermal classification of the established 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 60791, or evaluated in accordance with IEC 61857 (all parts).

---------------------- Page: 9 ----------------------

61858 © IEC:2004 – 11 –
ELECTRICAL INSULATION SYSTEMS –
THERMAL EVALUATION OF MODIFICATIONS TO
AN ESTABLISHED WIRE-WOUND EIS
1 Scope
This International Standard 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 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 60791 or has
been evaluated by one of the procedures given in the IEC 61857 series.
2 Normative references
The following referenced documents are indispensable for the application 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 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, Specifications for particular types of winding wires
NOTE Annex A cites several parts relating to the IEC 60317 series.
IEC 60505, Evaluation and qualification of electrical insulation systems
IEC 60791, Performance evaluation of insulation systems based on service experience and
functional tests
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, Electrical insulation systems – Procedures for thermal evaluation – Part 1:
General requirements – Low voltage
IEC 62114, Electrical insulation systems (EIS) – Thermal classification

---------------------- Page: 10 ----------------------

61858 © IEC:2004 – 13 –
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
electrical insulation system (EIS)
insulating structure containing one or more electrical insulating materials (EIM) together with
associated conducting parts employed in an electrotechnical device
3.2
electrical insulating material (EIM)
material with negligibly low electric conductivity, used to separate conducting parts at different
electrical potentials
4 General considerations
This standard provides relatively low cost and short-time methods by which the user can
make modifications to an established EIS by evaluating
a) the impact on the thermal life of the EIS if the thickness of an EIM is changed,
b) the compatibility, under thermal stress, of a substituted EIM,
c) the compatibility, under thermal stress, of other components used in intimate contact with
an established EIS.
EIM having different temperature indices (ATE/RTE) according to IEC 60216-5 may be
combined to form an EIS having a thermal class that may be higher or lower than that of any
of the individual components according to IEC 60505.
There may be more than one EIS in a particular apparatus. These EIS may have different
thermal classes.
The following overview (Figure 1) is a flow chart for guidance in selecting the proper clauses
for evaluation.

---------------------- Page: 11 ----------------------

61858 © IEC:2004 – 15 –
Established EIS per IEC 60791
or IEC 61857-1
EIM modification of established EIS Evaluation of additions to
established EIS
Addition of Addition
Change of
Substitution of EIM component
impregnating resin/ of other
thickness
varnish components
(5)
(9.1) (9.2)
Impregnating
Winding
resin/varnish Other EIM(8)
Wire (6)
(7)
Compare Substitution Substitution Substitution
thermal allowed? (8.2) allowed? (8.1) allowed? (6.1)
cl
...