IEC TR 61858-3:2020

Electrical insulation systems - Thermal evaluation of modifications to an established electrical insulation system (EIS) - Part 3: Clarification of electrical insulating materials (EIMs) and auxiliary materials

IEC TR 61858-3:2020(E) provides information on the identification of electrical insulating materials and auxiliary components for the assessment of modifications to an established insulation system and gives guidance on the selection of feasible test procedures.

General Information

• Status: Published
• Publication Date: 07-Dec-2020
• ICS: 29.080.30 - Insulation systems
• Technical Committee: TC 112 - Evaluation and qualification of electrical insulating materials and systems
• Drafting Committee: WG 6 - TC 112/WG 6
• Current Stage: PPUB - Publication issued
• Start Date: 18-Dec-2020
• Completion Date: 08-Dec-2020

Standards Content (Sample)

IEC TR 61858-3 ®
Edition 1.0 2020-12
TECHNICAL
REPORT
Electrical insulation systems – Thermal evaluation of modifications to an
established electrical insulation system (EIS)
Part 3: Clarification of electrical insulating materials (EIMs) and auxiliary
materials
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IEC TR 61858-3 ®
Edition 1.0 2020-12
TECHNICAL
REPORT
Electrical insulation systems – Thermal evaluation of modifications to an

established electrical insulation system (EIS)

Part 3: Clarification of electrical insulating materials (EIMs) and auxiliary

materials
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.080.30 ISBN 978-2-8322-9135-1

– 2 – IEC TR 61858-3:2020 © IEC 2020
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 General information . 7
4.1 Purpose of evaluation . 7
4.2 Categories of evaluation . 7
5 Evaluation procedures . 8
5.1 Procedure G – Proof of generic identical materials . 8
5.2 Procedure A – Without test . 8
5.3 Procedure B – Chemical compatibility test . 8
5.4 Procedure C – Standard single-point thermal aging test . 8
5.5 Procedure D – Full thermal aging . 8
6 EIS assessment . 8
Bibliography . 9

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL INSULATION SYSTEMS – THERMAL EVALUATION OF
MODIFICATIONS TO AN ESTABLISHED ELECTRICAL
INSULATION SYSTEM (EIS)
Part 3: Clarification of electrical insulating
materials (EIMs) and auxiliary materials

FOREWORD
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IEC TR 61858-3 has been prepared by IEC technical committee 112: Evaluation and
qualification of electrical insulating materials and systems. It is a Technical Report.
The text of this Technical Report is based on the following documents:
Draft Report on voting
112/465/DTR 112/500A/RVDTR
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 Technical Report is English.

– 4 – IEC TR 61858-3:2020 © IEC 2020
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 61858 series, published under the general title Electrical insulation
systems – Thermal evaluation of modifications to an established electrical insulation system
(EIS), can be found on the IEC website.
The committee has decided that the contents of this 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,
• withdraw
...