IEC 61857-32:2019

IEC 61857-32 ®
Edition 1.0 2019-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electrical insulation systems – Procedures for thermal evaluation –
Part 32: Multifactor evaluation with increased factors during diagnostic testing

Systèmes d'isolation électrique – Procédures d'évaluation thermique –
Partie 32: Évaluation multifactorielle avec facteurs augmentés pendant
les essais de diagnostic
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IEC 61857-32 ®
Edition 1.0 2019-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electrical insulation systems – Procedures for thermal evaluation –

Part 32: Multifactor evaluation with increased factors during diagnostic testing

Systèmes d'isolation électrique – Procédures d'évaluation thermique –

Partie 32: Évaluation multifactorielle avec facteurs augmentés pendant

les essais de diagnostic
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.080.30 ISBN 978-2-8322-7463-7

– 2 – IEC 61857-32:2019 © IEC 2019
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Procedure . 7
5 Test objects . 7
6 EIS evaluation . 7
7 Part 1: Baseline structure . 8
7.1 General . 8
7.2 Illustration of the structure – Thermal evaluation . 8
7.3 Example of thermal evaluation of a candidate EIS . 9
8 Part 2: Evaluation of other factors . 10
8.1 General . 10
8.2 Selection of the ageing temperature for the one-temperature comparison . 10
8.3 Application of increased or additional diagnostic factors . 11
9 Analysis of data . 11
9.1 General . 11
9.2 Evaluation of the other factors of influence . 11
9.3 Comparison of the results is between the baseline EIS and any of the sets of
results for other factors of influence . 11
10 Report . 12
Bibliography . 13
Annex A (informative)  Example of a test data sheet report . 14
Annex B (informative) Example of thermal ageing data for the reference EIS –
Establishing the correlation time . 15
Annex C (informative) Example of a test data sheet for a baseline candidate thermal
classification . 16
Annex D (informative) Establishing the thermal endurance of the baseline candidate
using the reference correlation time . 17

Figure 1 – Overview . 7
Figure 2 – Illustration of the establishment of the thermal classification of
the candidate EIS . 9
Figure B.1 – Reference data with the known temperature of 186 °C, time coordinate
established at 45 200 h . 15
Figure D.1 – Baseline candidate data with the known thermal index of 161 °C when the
time coordinate from the reference is 45 200 hours . 17

Table 1 – Example of a reference EIS and candidate EIS; performance at temperature
and thermal classification. 9
Table 2 – Example of ageing temperature selection for the one-temperature
comparison . 10
Table A.1 – Example of a test data sheet . 14
Table C.1 – Example of a test data sheet for a baseline candidate . 16

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL INSULATION SYSTEMS – PROCEDURES
FOR THERMAL EVALUATION –
Part 32: Multifactor evaluation with increased
factors during diagnostic testing

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
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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 61857-32 has been prepared by IEC technical committee 112:
Evaluation and qualification of electrical insulating materials and systems
The text of this International Standard is based on the following documents:
CDV Report on voting
112/399/CDV 112/425A/RVC
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

– 4 – IEC 61857-32:2019 © IEC 2019
A list of all parts in the IEC 61857 series, published under the general title Electrical insulation
systems – Procedures for thermal evaluation, 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 "http://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.
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.
INTRODUCTION
Accelerated ageing of an Electrical Insulation System [EIS] is intended to evaluate the
thermal classification of the EIS. Many applications need to include the evaluation of other
factors in addition to the thermal factor related to the application.
IEC 60505 provides four categories of stresses or ageing factors which influence the
performance of products in use under a wide range of operating conditions. In IEC 60505, the
factors are presented as Thermal [T], Electrical [E], Environmental [E], and Mechanical [M]. In
this part of IEC 61857, Environmental [E] is replaced with Ambient [A] to remove possible
confusion of having two factors represented by the same letter. For this document, the factors
are presented with Thermal [T], Electrical [E], Ambient [A], and Mechanical [M].
This document provides the structure for evaluation of one or more of the three factors E, A
and M by direct comparison to the baseline classification established by T. Without the
baseline, any analysis is limited.
While similar, IEC 61857-32 and IEC 61857-33 have different structure and evaluation
conditions. In IEC 61857-32, thermal exposure is the only intended ageing factor and
additional stresses are only applied during the diagnostic portion of each test cycle. In
IEC 61857-33, the stresses are applied continually at elevated temperatures.

– 6 – IEC 61857-32:2019 © IEC 2019
ELECTRICAL INSULATION SYSTEMS – PROCEDURES
FOR THERMAL EVALUATION –
Part 32: Multifactor evaluation with increased
factors during diagnostic testing

1 Scope
This part of the 61857 series is focused on applications where other possible factors need to
be incorporated to evaluate any influence on the performance of the electrical insulation
system (EIS). Multi-factor evaluation is the most complex type of project to design and
conduct. Clear guidelines are needed to give the user of this document a uniform approach
and a method to analyse the test results.
This document is for applications where the stresses are some combination of other factors of
influence identified in IEC 60505. The multi-factor stresses are applied during the diagnostic
portion of each test cycle.
A few examples of other factors of influence or multi-factor stresses are:
– high vibration;
– submersion in oils, water, or solutions;
– voltage higher than the test voltage of the reference EIS;
– decreased cold shock temperature.
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 61857-1, Electrical insulation systems – Procedures for thermal evaluation – Part 1:
General requirements – Low-voltage
IEC TR 61857-2, Electrical insulation systems – Procedures for thermal evaluation – Part 2:
Selection of the appropriate test method for evaluation and classification of electrical
insulation systems
IEC 61858-2, Electrical insulation systems – Thermal evaluation of modifications to an
established electrical insulation system (EIS) – Part 2: Form-wound EIS
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61857-1 and the
following 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
baseline candidate EIS
EIS exposed to the same thermal ageing and conditioning as the reference EIS
3.2
reference EIS
EIS of a known or field proven design used to establish the thermal classification of the
candidate EIS
3.3
EIS
RT
established thermal classification of the reference EIS
3.4
EIS
CT
assigned thermal classification of the candidate EIS based on the comparison to the reference
EIS
4 Procedure
An overview of the structure is shown in Figure 1.
Reference Baseline
Electrical [E]
candidate
EIS
RT
EIS
CT
Ambient [A]
Mechanical [M]
IEC
Figure 1 – Overview
5 Test objects
Test objects shall be in accordance with the test method selected from IEC TR 61857-2.
The design of test object(s) shall be in accordance with the test method selected. When part
of the evaluation is to compare processing or alternate designs of the same functioning
product, the modifications shall be part of the multifactor test object construction with all
modifications documented in the report.
The preferred number of test objects is contained in the individual test method selected from
IEC TR 61857-2.
6 EIS evaluation
The evaluation of the endurance of the candidate EIS and evaluation with multifactor stresses
is separated into two parts.
– 8 – IEC 61857-32:2019 © IEC 2019
Part 1: evaluation of the baseline candidate EIS under standard exposure, conditioning, and
testing to establish the baseline performance.
Part 2: evaluation of the possible influence of other factors on the performance of the EIS by
conducting a one-temperature side-by-side comparison with one set of test objects
undergoing evaluation with standard exposure, conditioning, and testing and the second set of
test objects undergoing evaluation with the same thermal exposure but including the other
stress factor(s) during conditioning and/or testing.
The baseline candidate EIS and EIS undergoing evaluation with other/increased stresses are
expected to utilize the same materials and be of the same design and construction. The only
factor expected to be different between the two sets of test specimens/objects is the
diagnostic stress during the diagnostic portion of the evaluation, unless the purpose of the
test is to evaluate a manufacturing/process change.
7 Part 1: Baseline structure
7.1 General
Part 1 consists of the evaluation of a candidate system compared to a reference system or a
pre-selected correlation time in accordance with one of the test methods selected from
IEC TR 61857-2. The candidate and reference systems shall be evaluated in the same
manner. This is essential for analysis of the results. In addition, all sets of test objects shall
be of the same design and construction unless the purpose of the test is to evaluate design
changes. The thermal class of the reference and candidate systems may be different. There is
no requirement for the reference and candidate EIS to have the same thermal classification,
as the thermal classification of the candidate EIS cannot be known until completion of the
thermal ageing.
NOTE In a situation where no established reference EIS can be identified a preselected time coordinate is usable
as the means to establish the thermal classification of the baseline candidate EIS.
The candidate EIS is evaluated to establish the thermal endurance performance by direct
comparison to the selected reference EIS or pre-selected correlation time. The performance
of the candidate EIS when exposed to thermal stress and conditions in accordance with the
standard EIS test method(s) becomes the baseline needed to evaluate the influence of the
additional stresses.
In Part 1, the reference EIS and baseline candidate EIS may have different thermal classes,
which means that the thermal ageing temperatures used during the evaluation may be
different. Part 2, for the evaluation of the baseline candidate EIS and the EIS which has
increased/additional diagnostic factors, requires both EIS to be exposed to the same thermal
ageing temperature for the same duration (thermal ageing hours) each cycle.
7.2 Illustration of the structure – Thermal evaluation
The candidate EIS performance is compared to a reference EIS to establish the thermal
endurance of the candidate EIS as illustrated in Figure 2.

Baseline
Reference
candidate
EIS
RT
EIS
CT
IEC
Key
EIS established thermal classification of the reference EIS
RT
EIS assigned thermal classification of the candidate EIS based on comparison to the reference EIS
CT
Figure 2 – Illustration of the establishment of the thermal classification
of the candidate EIS
7.3 Example of thermal evaluation of a candidate EIS
The thermal evaluation of a candidate EIS typically consists of the exposure of test objects to
a minimum of three thermal ageing temperatures (one set of test objects per temperature, per
EIS being evaluated). The thermal ageing temperatures, number of test objects, etc. are
indicated in the appropriate EIS test method selected from IEC TR 61857-2.
Temperature 1 = highest
Temperature 2 = middle
Temperature 3 = lowest
The total number of sets of test objects needed = 3 reference + 3 candidate = 6 sets.
Table 1 provides an example showing the comparison of the performance of a possible
reference EIS to the performance of a possible candidate EIS.
Annex A provides an example of test data for a reference EIS with an example of the plotting
of the reference EIS data in Annex B.
Annex C provides an example of test data for a candidate EIS with an example of the plotting
of the candidate EIS data in Annex D.
Table 1 – Example of a reference EIS and candidate EIS; performance
at temperature and thermal classification
Thermal ageing Reference life at temperature Candidate life at temperature
temperatures [hours] [hours]
Highest = 240 °C H = 350 H = 480
R Y
Middle = 220 °C M = 1 600 M = 1 900
R Y
Lowest = 200 °C L = 5 700 L = 6 900
R Y
Thermal rating Thermal index = 180 °C Relative thermal index = 181 °C
Correlation time based on known thermal RTI based on comparison to the reference
index = 29 239 h system correlation time

– 10 – IEC 61857-32:2019 © IEC 2019
8 Part 2: Evaluation of other factors
8.1 General
Part 2 includes the one-temperature comparison of a baseline EIS to a multi-factor EIS.
The multi-factor evaluation requires one set of test objects for the baseline EIS and a set of
test objects for each additional stress or change in diagnostic level to be evaluated (one set
per factor/evaluation). Prior to the start of the program, each potential factor should be
identified for potential inclusion into the total test program.
Once the thermal classification of the baseline candidate EIS has been established, the
assigned rating of the EIS does not change under the multifactor evaluation. The multifactor
evaluation is used to determine the potential impact of other factors on the performance of the
established EIS, which can be of value in end product design, manufacturing, or for potential
use of the EIS in specific applications.
8.2 Selection of the ageing temperature for the one-temperature comparison
The temperature selected shall reflect the expected operating temperature. When the
expected operating temperature is not known, the middle ageing temperature used to
evaluate the candidate EIS during comparison to a reference EIS shall be used. The preferred
temperature selected is one which resulted in a life in the range of 1 000 h to 1 500 h during
the baseline candidate evaluation. Table 2 provides an example of ageing temperature
selection for the one-temperature comparison.
Table 2 – Example of ageing temperature selection for
the one-temperature comparison
Thermal ageing Baseline candidate life at One-temperature comparison – Selected
temperatures temperature thermal ageing temperature
[hours]
Highest = 240 °C H = 480 230 °C
Y
Middle = 220 °C M = 1 900 Based on the known life at temperature and
Y
using the 10 °rule, thermal ageing at 230 °C
Lowest = 200 °C L = 6 900
should result in a life of approximately 900 h to
Y
1 000 h
All evaluations for the influence of additional factors are made by comparison of the thermal
performance of the multifactor candidate EIS to the thermal performance of the baseline
candidate EIS as the thermal factor is common to all combinations. Comparisons shall
CT
establish the influence of the additional factors on the EIS. Comparison is not made to the
reference EIS , which was used to establish the thermal rating and performance of the
RT
baseline candidate EIS .
CT
The thermal exposure at elevated temperature is separated into ageing cycles. The thermal
exposure and ageing cycles shall be the same for the baseline candidate and multifactor
candidate.
If agreed upon, evaluation of the multifactor candidate compared to the baseline candidate
and comparison of the baseline candidate to the reference may be conducted concurrently.

8.3 Application of increased or additional diagnostic factors
Following each ageing cycle, the set of test objects for the baseline candidate EIS are
conditioned and tested in accordance with the appropriate test method selected from
IEC TR 61857-2.
Following each ageing cycle, the set of test objects for the multi-factor EIS are conditioned
and evaluated in a similar manner except for the inclusion of the additional or increased
factors.
Additional factors to be used in determining the end-of-test shall have a preselected limit to
the change of performance to define the end-of-test for the selected property.
9 Analysis of data
9.1 General
The thermal endurance of the baseline candidate EIS is determined in accordance with the
test method selected from IEC TR 61857-2.
9.2 Evaluation of the other factors of influence
The EIS test methodology has an assumed repeatability of ±5 °C. This means the EIS test
method gives results within ±5 °C on repeated tests of the same EIS; this is often called the
"5-degree rule". The 5-degree rule means that when two sets of test results are within 5 °C of
each other, the test method cannot distinguish the two sets of results. The 5-degree rule does
not imply that the two sets are equal, only that the two sets are not distinguishable and the
same rating can be assigned to both sets. The 5-degree rule is essential for the evaluation of
the influence of other factors on the performance of the EIS.
Use the 5-degree rule in procedure C of IEC 61858-2 with
a) the baseline candidate EIS becoming the reference in the calculation and comparison of
the influence of the additional factor(s),
b) the result of the 1-temperature set being the candidate in the calculation.
9.3 Comparison of the results is between the baseline EIS and any of the sets of
results for other factors of influence
When the difference is equal to or less than 5 °C, the analysis is the factor under test does
not have a significant influence in the overall performance of the EIS.
When the difference is greater than 5 °C, the influence of the factor under test is identified as
causing a measurable change in the performance of the EIS.
When the difference shows the influence of the other factor increases the performance by
more than 5 °C, the analysis indicates the condition can be expected to extend the potential
operating life of the EIS.
NOTE 1 An example of increase in performance: the EIS is evaluated immersed in a liquid or treated with a resin
system which restricts oxygen from reaching the EIS. The exclusion of oxygen can slow the decomposition process
and result in an extended life performance.
When the difference shows that the influence of the other factor reduces the performance by
more than 5 °C, the magnitude or shift of the expected endurance shall be evaluated to
determine if the downward shift can be used for the application.
NOTE 2 An example for a downward shift where the difference is greater than 5 °C and can be usable: the
thermal endurance index value is 194 °C. The difference is 8 °C. The implied result of the factor of influence would

– 12 – IEC 61857-32:2019 © IEC 2019
be a thermal endurance index value of 194 °C – 8 °C = 186 °C. With the shift still being well into the 180-class, it
could be agreed that the downshift is acceptable.
10 Report
The report of the results of this test shall include all records, relevant details of the test, and
analysis, including:
– reference to this IEC test standard and applicable part;
– description of the candidate EIS tested;
– description of each added factor of influence;
– prediagnostic conditioning and diagnostic tests used with applied test or stress levels, for
the baseline EIS and for each additional set;
– number of test objects at each temperature for each set of test objects;
– method of obtaining the ageing temperatures (including oven type, etc.);
– ageing temperatures and ageing periods of the base-line EIS;
– ageing temperature and ageing periods of each one-temperature set;
– individual times to end-of-life, and mode of failure;
– mean log times to end-of-life for each ageing temperature set;
– EIS RTE/thermal class of the baseline candidate EIS, each additional set and the
difference between the baseline EIS and that of each factor.

Bibliography
IEC 60505, Evaluation and qualification of electrical insulation systems

– 14 – IEC 61857-32:2019 © IEC 2019
Annex A
(informative)
Example of a test data sheet report
Table A.1 shows an example of a test data sheet report.
Table A.1 – Example of a test data sheet
Identification of the testing laboratory:
Project tracking designation: Example
EIS designation: Reference EIS: Reference – example
Date of test [start to completion]:
Other essential project information: Selected from IEC TR 61857-2
Test object number H 220 °C M 210 °C L 200 °C
R R R
[hours] [hours] [hours]
1 336 1 428 5 040
2 306 1 092 5 040
3 336 1 596 7 056
4 252 1 092 5 712
5 420 1 428 6 384
6 336 1 596 4 368
7 420 1 596 7 056
8 336 1 092 5 040
9 306 1 260 4 368
10 336 1 260 5 712
Log average life 335 1 329 5 500
H = highest ageing temperature data
R
M = middle ageing temperature data
R
L = lowest ageing temperature data
R
Known thermal index value: 186 °C

Annex B
(informative)
Example of thermal ageing data for the reference EIS – Establishing the
correlation time
The correlation time is the time coordinate in hours which is needed to establish the thermal
classification of the baseline candidate EIS. The life at temperature is established based on
the thermal ageing, conditioning, and testing of the reference EIS in accordance with the EIS
test method selected from IEC TR 61857-2.
The graph of the data in Figure B.1 is provided only as an example. In this example, the
thermal index rating of the reference was established to be 186 °C. The time/temperature line
is extended beyond and below the 180 °C temperature coordinate, which to cover the
established known rating of 186 °C. The time coordinate when the temperature coordinate of
186 °C is determined becomes the correlation time to be used for the evaluation of the
baseline candidate EIS. This time coordinate is now referred to as the correlation time. In this
example, the time coordinate when the temperature coordinate is 186 °C is 45 200 h.
100 000
Slope = 14 169,39
10 000
1 000
180 190 200 220 230 Temperature (°C)
IEC
Figure B.1 – Reference data with the known temperature of 186 °C,
time coordinate established at 45 200 h
Life (hours)
– 16 – IEC 61857-32:2019 © IEC 2019
Annex C
(informative)
Example of a test data sheet for a baseline candidate
thermal classification
Table C.1 shows an example of a test data sheet for a baseline candidate.
Table C.1 – Example of a test data sheet for a baseline candidate
Identification of the testing laboratory:
Project tracking designation: Example
EIS designation: Baseline candidate – example
Date of test [start to completion]:
Other essential project information: Selected from IEC TR 61857-2
Test object number H 200 °C M 190 °C L 180 °C
C C C
[hours] [hours] [hours]
1 640 1 970 4 900
2 504 2 100 5 200
3 756 2 500 5 206
4 504 1 970 5 326
5 756 2 100 5 000
6 924 1 848 4 900
7 924 1 848 5 326
8 640 1 700 5 200
9 504 2 000 5 180
10 640 1 970 5 180
Log average life 663 1 991 5 140
H = highest ageing temperature data
C
M = middle ageing temperature data
C
L = lowest ageing temperature data
C
Correlation time, from the reference EIS: 45 200 h
Baseline candidate thermal rating: 161 °C temperature coordinate when the time coordinate is 45 200 h.

Annex D
(informative)
Establishing the thermal endurance of the baseline candidate
using the reference correlation time
The data from Table C.1 is used to plot the performance of the baseline candidate EIS. The
thermal index assigned to the baseline is the temperature coordinate where the
time/temperature line crosses the time coordinate of the correlation time, using the
information in Table A.1 and Figure B.1. In this example, the correlation time from Figure B.1
is used to determine the temperature coordinate of the time/temperature line (see Figure D.1).
100 000
Slope = 9 522,53
10 000
1 000
170 180 190 200 210
Temperature (°C)
IEC
Figure D.1 – Baseline candidate data with the known thermal index of 161 °C
when the time coordinate from the reference is 45 200 hours
___________
Life (hours)
– 18 – IEC 61857-32:2019 © IEC 2019
SOMMAIRE
AVANT-PROPOS . 19
INTRODUCTION . 21
1 Domaine d'application . 22
2 Références normatives . 22
3 Termes et définitions . 22
4 Procédure . 23
5 Éprouvettes . 23
6 Évaluation du SIE . 23
7 Partie 1: Structure de base . 24
7.1 Généralités . 24
7.2 Représentation de la structure – Evaluation thermique . 24
7.3 Exemple d'évaluation thermique d'un SIE candidat . 25
8 Partie 2: Évaluation des autres facteurs . 26
8.1 Généralités . 26
8.2 Choix de la température de vieillissement pour une comparaison à une
température . 26
8.3 Application de facteurs de diagnostic augmentés ou supplémentaires . 27
9 Analyse des données . 27
9.1 Généralités . 27
9.2 Évaluation des autres facteurs d'influence . 27
9.3 Comparaison des résultats entre le SIE de base et l'un des ensembles de
résultats pour d'autres facteurs d'influence . 27
10 Compte-rendu. 28
Bibliographie . 29
Annexe A (informative) Exemple de compte-rendu technique d'essai . 30
Annexe B (informative) Exemple de données de vieillissement thermique pour le SIE
de référence – Établissement du temps de corrélation . 31
Annexe C (informative) Exemple de fiche technique d'essai pour la classification
thermique d'un candidat de base . 32
Annexe D (informative) Établissement de l'endurance thermique du candidat de base
à l'aide du temps de corrélation de référence . 33

Figure 1 – Vue d’ensemble . 23
Figure 2 – Représentation de l'établissement de la classification thermique du SIE
candidat . 25
Figure B.1 – Données de référence avec la température connue de 186 °C,
coordonnée de temps établie à 45 200 h . 31
Figure D.1 – Données du candidat de base avec l'indice thermique connu de 161 °C
lorsque la coordonnée de temps de la référence est de 45 200 h . 33

Tableau 1 – Exemple de SIE de référence et de SIE candidat; performances à
température et classification thermique . 25
Tableau 2 – Exemple de température de vieillissement pour la comparaison à une
température . 26
Tableau A.1 – Exemple de compte-rendu technique d'essai . 30
Tableau C.1 – Exemple de fiche technique d'essai pour un candidat de base . 32

COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
SYSTÈMES D'ISOLATION ÉLECTRIQUE –
PROCÉDURES D'ÉVALUATION THERMIQUE –

Partie 32: Évaluation multifactorielle avec facteurs
augmentés pendant les essais de diagnostic

AVANT-PROPOS
1) La Commission Electrotechnique Internationale (IEC) est une organisation mondiale de normalisation
composée de l'ensemble des comités électrotechniques nationaux (Comités nationaux de l’IEC). L’IEC a pour
objet de favoriser la coopération internationale pour toutes les questions de normalisation dans les domaines
de l'électricité et de l'électronique. A cet effet, l’IEC – entre autres activités – publie des Normes
internationales, des Spécifications techniques, des Rapports techniques, des Spécifications accessibles au
public (PAS) et des Guides (ci-après dénommés "Publication(s) de l’IEC"). Leur élaboration est confiée à des
comités d'études, aux travaux desquels tout Comité national intéressé par le sujet traité peut participer. Les
organisations internationales, gouvernementales et non gouvernementales, en liaison avec l’IEC
...