EN 60085:2008

Electrical insulation - Thermal evaluation and designation

IEC 60085:2007 now distinguishes between thermal classes for electrical insulation systems and electrical insulating materials. It establishes the criteria for evaluating the thermal endurance of either electrical insulating materials (EIM) or electrical insulation systems (EIS). It also establishes the procedure for assigning thermal classes. This standard is applicable where the thermal factor is the dominant ageing factor. The major technical changes with regard to the previous edition concern the fact that this edition is an amalgamation of the third edition of this standard together with IEC 62114:2001. It has the status of a horizontal standard in accordance with IEC Guide 108.

Elektrische Isolierung - Thermische Bewertung und Bezeichnung

Isolation électrique - Evaluation et désignation thermiques

La CEI 60085:2007 fait à présent la distinction entre les classes thermiques pour systèmes d'isolation électrique et matériaux isolants électriques. Elle établit les critères d'évaluation de l'endurance thermique des matériaux isolants électriques (EIM, electrical insulating materials) ou des systèmes d'isolation électrique (EIS, electrical insulation systems). Elle établit également la procédure d'attribution des classes thermiques. Cette norme s'applique lorsque le facteur thermique est le facteur de vieillissement prépondérant. Les modifications techniques majeures par rapport à l'édition précédente concernent le fait que la présente édition est une fusion entre la troisième édition de cette norme et la CEI 62114:2001. Elle a le statut d'une norme horizontale conformément au Guide 108 de la CEI.

Ocenjevanje toplotnih lastnosti in označevanje električne izolacije (IEC 60085:2007)

General Information

• Status: Published
• Publication Date: 10-Jan-2008
• Withdrawal Date: 30-Nov-2010
• ICS: 17.220.99 - Other standards related to electricity and magnetism
• ICS: 29.035.01 - Insulating materials in general
• Technical Committee: CLC/SR 112 - Evaluation and qualification of electrical insulating materials and systems (to be defined)
• Drafting Committee: IEC/TC 112 - IEC_TC_112
• Parallel Committee: IEC/TC 112 - IEC_TC_112
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 11-Jan-2008
• Completion Date: 11-Jan-2008
• Ref Project: SIST EN 60085:2008 - Electrical insulation - Thermal evaluation and designation

Relations

• Replaces: EN 62114:2001 - Electrical insulation systems (EIS) - Thermal classification
• Effective Date: 28-Jan-2023
• Replaces: EN 60085:2004 - Electrical insulation - Thermal classification
• Effective Date: 28-Jan-2023

Overview

EN 60085:2008, titled Electrical insulation - Thermal evaluation and designation, is a European standard aligned with IEC 60085:2007, published and maintained by CLC (European Committee for Electrotechnical Standardization). This standard addresses the thermal evaluation and classification of electrical insulating materials (EIM) and electrical insulation systems (EIS). It specifies criteria and procedures for assessing the thermal endurance of both EIM and EIS, essential for ensuring reliable performance and longevity in electrotechnical devices where thermal aging is the dominant factor affecting insulation integrity.

This edition merges the previous EN 60085:2004 with EN 62114:2001, streamlining requirements and harmonizing methods for thermal class designation. EN 60085:2008 serves as a horizontal standard applicable across a broad range of electrical and electronic equipment where thermal effects on insulation are critical.

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Key Topics

• Thermal Classes for Electrical Insulation
  The standard distinguishes thermal classes between electrical insulating materials and systems, describing maximum continuous use temperatures that define insulation durability under thermal stress.

• Thermal Endurance Assessment
  EN 60085 outlines evaluation methods based on the thermal endurance index (ATE) and relative thermal endurance index (RTE) for both materials (EIM) and systems (EIS), referencing related IEC standards such as IEC 60216 and IEC 60505.

• Relationship Between Materials and Systems
  The standard clarifies that the thermal class of an insulation system (EIS) may not directly correlate with the thermal endurance of individual materials (EIM) within. Synergistic effects or material incompatibilities within EIS may increase or decrease overall thermal performance.

• Scope of Application
  EN 60085 is applicable where the thermal factor is the primary cause of insulation aging, which is common in rotating machines, transformers, and other electrical devices.

• Thermal Class Designation Table
  Thermal classes are designated by numerical values representing the maximum continuous operating temperature in °C, accompanied optionally by letter designations (e.g., 180(H)). Classes range from 90°C (Class Y) and increase in increments, covering typical and high-temperature applications up to and beyond 250°C.

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Applications

EN 60085:2008 is crucial for engineers, designers, and manufacturers involved in:

• Designing Electrical Insulation Systems
  Ensures correct selection and qualification of insulating materials and systems based on thermal endurance for components such as stators, rotors, transformers, and electric motors.

• Product Quality and Safety Assurance
  Provides standardized thermal class limits to guarantee products meet safety and longevity requirements under defined operational temperature conditions.

• Thermal Aging Testing and Certification
  Guides testing laboratories and certification bodies in determining the thermal classification of new insulating materials or systems through standardized ageing procedures.

• Maintenance and Lifecycle Management
  Aids asset managers in predicting insulation lifespan and scheduling preventive maintenance based on thermal stress profiles.

• Development of New Materials and Technologies
  Supports research institutions and manufacturers in benchmarking and improving the thermal endurance of novel electrical insulating materials.

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Related Standards

EN 60085:2008 integrates and refers to several complementary IEC standards essential for comprehensive thermal evaluation of insulation:

• IEC 60216-1 & IEC 60216-5
  Define ageing procedures and determination of relative thermal endurance indexes for electrical insulating materials.

• IEC 60505
  Provides evaluation and qualification methods specifically for electrical insulation systems.

• IEC 61857 Series & IEC 61858
  Detail procedures for thermal evaluation and modification assessment for wire-wound insulation systems.

• IEC 60216-6
  Focuses on determination of thermal endurance indices using fixed time frame methods.

These standards collectively ensure a robust, harmonized approach to thermal testing, evaluation, and classification across various electrical insulation applications.

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By adhering to EN 60085:2008, stakeholders ensure electrical insulation systems achieve optimal reliability and operational safety through scientifically validated thermal performance criteria, supporting innovation and regulatory compliance across the electrotechnical industry.

Standards Content (Sample)

SLOVENSKI STANDARD
01-marec-2008
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SIST EN 60085:2005
SIST EN 62114:2002
2FHQMHYDQMHWRSORWQLKODVWQRVWLLQR]QDþHYDQMHHOHNWULþQHL]RODFLMH,(&

Electrical insulation - Thermal evaluation and designation
Elektrische Isolierung - Thermische Bewertung und Bezeichnung
Isolation électrique - Evaluation et désignation thermiques
Ta slovenski standard je istoveten z: EN 60085:2008
ICS:
29.080.30 Izolacijski sistemi Insulation systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 60085
NORME EUROPÉENNE
January 2008
EUROPÄISCHE NORM
ICS 29.035.01; 17.220.99 Supersedes EN 60085:2004 and EN 62114:2001

English version
Electrical insulation -
Thermal evaluation and designation
(IEC 60085:2007)
Isolation électrique -  Elektrische Isolierung -
Evaluation et désignation thermiques Thermische Bewertung und Bezeichnung
(CEI 60085:2007) (IEC 60085:2007)

This European Standard was approved by CENELEC on 2007-12-01. 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, Bulgaria, Cyprus, the
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the 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

© 2008 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60085:2008 E
Foreword
The text of document 112/74/FDIS, future edition 4 of IEC 60085, prepared by IEC TC 112, Evaluation
and qualification of electrical insulating materials and systems, was submitted to the IEC-CENELEC
parallel vote and was approved by CENELEC as EN 60085 on 2007-12-01.
This European Standard supersedes EN 60085:2004 and EN 62114:2001.
The major technical changes with regard to EN 60085:2004 concern the fact that EN 60085:2008 is an
amalgamation of EN 60085:2004 together with EN 62114:2001.
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) 2008-09-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2010-12-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 60085:2007 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 60216-6 NOTE  Harmonized as EN 60216-6:2006 (not modified).
__________
- 3 - EN 60085:2008
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  When 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 60216-1 - Electrical insulating materials - Properties of EN 60216-1 2001
thermal endurance -
Part 1: Ageing procedures and evaluation of
test results
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
1) 2)
IEC 60505 - Evaluation and qualification of electrical EN 60505 2004
insulation systems
IEC 61857 Series Electrical insulation systems - Procedures for EN 61857 Series
thermal evaluation
1) 2)
IEC 61858 - Electrical insulation systems - Thermal EN 61858 2005
evaluation of modifications to an established
wire-wound EIS
1)
Undated reference.
2)
Valid edition at date of issue.

IEC 60085
Edition 4.0 2007-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electrical insulation – Thermal evaluation and designation

Isolation électrique – Evaluation et désignation thermiques

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
H
CODE PRIX
ICS 29.035.01; 17.220.99 ISBN 2-8318-9387-9

– 2 – 60085 © IEC:2007
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL INSULATION –
THERMAL EVALUATION AND DESIGNATION

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
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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 60085 has been prepared by technical committee 112: Evaluation
and qualification of electrical insulating materials and systems.
This fourth edition cancels and replaces the third edition, published in 2004, and constitutes a
technical revision.
The major technical changes with regard to the previous edition concern the fact that this
edition is an amalgamation of the third edition of this standard together with IEC 62114:2001.
The text of this standard is based on the following documents:
FDIS Report on voting
112/74/FDIS 112/77/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 ac
...