IEC TS 62371:2008

IEC/TS 62371
Edition 1.0 2008-05
TECHNICAL
SPECIFICATION
Characteristics of hollow pressurised and unpressurised ceramic and glass
insulators for use in electrical equipment with rated voltages greater than 1000 V

IEC/TS 62371:2008(E)
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IEC/TS 62371
Edition 1.0 2008-05
TECHNICAL
SPECIFICATION
Characteristics of hollow pressurised and unpressurised ceramic and glass
insulators for use in electrical equipment with rated voltages greater than 1000 V

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
S
ICS 29.080.10 ISBN 2-8318-9778-5

– 2 – TS 62371 © IEC:2008(E)
CONTENTS
FOREWORD.3
INTRODUCTION.5
1 Scope.6
2 Normative references .7
3 Terms and definitions .7
4 Dimensional and mechanical characteristics.8
5 Marking .9
6 Fixing arrangement.9
7 Designation of hollow insulators .9
Bibliography.22

Figure 1 – Example of a straight type hollow insulator with metal fittings on both ends .18
Figure 2 – Example of a taper type hollow insulator with metal fittings on both ends .19
Figure 3 – Example of a straight type hollow insulator without metal fittings.20
Figure 4 – Example of a taper type hollow insulator without metal fittings .21

Table 1 – Straight type hollow insulators with metal fittings on both ends.11
Table 2 – Taper type hollow insulators with metal fittings on both ends.12
Table 3 – Straight type hollow insulators without metal fittings.14
Table 4 – Taper type hollow insulators without metal fittings .16

TS 62371 © IEC:2008(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CHARACTERISTICS OF HOLLOW PRESSURISED
AND UNPRESSURISED CERAMIC AND GLASS INSULATORS
FOR USE IN ELECTRICAL EQUIPMENT WITH RATED VOLTAGES
GREATER THAN 1000 V
FOREWORD
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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
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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The main task of IEC technical committees is to prepare International Standards. In
exceptional circumstances, a technical committee may propose the publication of a technical
specification when
• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC 62371, which is a technical specification, has been prepared by subcommittee 36C:
Insulators for substations, of IEC technical committee 36: Insulators.

– 4 – TS 62371 © IEC:2008(E)
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
36C/172/DTS 36C/173/RVC
Full information on the voting for the approval of this technical specification 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.
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
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

TS 62371 © IEC:2008(E) – 5 –
INTRODUCTION
The IEC standards concerning insulators for overhead lines and substations are classified into
two categories. One is the standard for test methods and acceptance criteria and the other is
the product standard in which characteristics of the insulators are specified. Product
standards of most insulators, for example cap and pin type, long rod type insulators for
overhead lines and station post insulators for substations, are available.
In the case of hollow insulators, test methods and acceptance criteria are standardized in
IEC 62155: Hollow pressurized and unpressurized ceramic and glass insulators for use in
electrical equipment with rated voltages greater than 1 000 V, but there has been no product
standard. This seems due to the difference in application among hollow insulators and other
insulators. The hollow insulators are usually applied as a component of electrical equipment
and other insulators such as cap and pin type or station post insulators are directly applied to
the power system as equipment.
There are benefits for standardization of the hollow insulators, even if they are used as
components, for insulator manufacturers, equipment manufacturers and final users for the
equipment. That is, benefits of cost saving in respect of manufacturing and inventory control,
short delivery, interchangeability, etc.
Taking account of every aspect on standardization of the hollow insulators, such as the fact
that there are so many designs of electrical equipment, this Technical Specification covers
only basic hollow insulators for normal application as a first step towards standardization work.
Accordingly, special types of hollow insulators such as barrel type for some circuit-breakers,
insulators for pollution and/or seismic areas, etc. are not within the scope of this specification.
Therefore, different hollow insulators not included in this specification can also be applied to
the electrical equipment in the case where special characteristics are required, depending on
environmental and/or system conditions. There may be the possibility to standardize those
hollow insulators as a next step after gathering sufficient information on experiences.
In addition, it should be noted that the characteristics specified here are determined,
considering the data collected through the survey on the presently available hollow insulators.
There may be the possibility that the survey is not complete and then the hollow insulators not
covered by this technical specification can also be applied. Such insulators as widely applied
but not covered by this technical specification will be added in the next revision through
ascertained experiences.
– 6 – TS 62371 © IEC:2008(E)
CHARACTERISTICS OF HOLLOW PRESSURISED
AND UNPRESSURISED CERAMIC AND GLASS INSULATORS
FOR USE IN ELECTRICAL EQUIPMENT WITH RATED VOLTAGES
GREATER THAN 1000 V
1 Scope
This Technical Specification applies to
– ceramic and glass hollow insulators intended for general use in electrical equipment;
– ceramic hollow insulators intended for use with a permanent gas pressure in switchgear
and controlgear.
They are intended for indoor and outdoor use in electrical equipment, operating on alternating
current with a rated voltage greater than 1 000 V and a frequency not greater than 100 Hz or
for use in direct current equipment with a rated voltage greater than 1 500 V.
This specification specifies the dimensional and mechanical characteristics of the hollow
insulator, which are essential for interchangeability of the hollow insulator of the same type. It
is not the object of this specification to prescribe electrical characteristics because they are
dependent on the apparatus of which the hollow insulator ultimately forms a part. However,
standard lightning impulse withstand voltage which is provided in IEC 60071-1 is described
only for reference for classification purpose.
This specification applies to hollow insulators for use in electrical equipment in clean areas or
lightly polluted areas, where seismic qualification is not required. For use in areas
characterised by heavy pollution levels and for other particular or extreme environmental
conditions such as seismic force, it may be necessary for certain dimensions to be changed.
The hollow insulators covered by this specification are:
a) straight type hollow insulators with metal fittings on both ends;
b) taper type hollow insulators with metal fittings on both ends;
c) straight
...