IEC 60305:2021

Insulators for overhead lines with a nominal voltage above 1000 V - Ceramic or glass insulator units for AC systems - Characteristics of insulator units of the cap and pin type

IEC 60305:2021

Name:IEC 60305:2021   Standard name:Insulators for overhead lines with a nominal voltage above 1000 V - Ceramic or glass insulator units for AC systems - Characteristics of insulator units of the cap and pin type
Standard number:IEC 60305:2021   language:English language
Release Date:10-Jan-2021   technical committee:TC 36 - Insulators
Drafting committee:MT 17 - TC 36/MT 17   ICS number:29.080.10 - Insulators

IEC 60305
Edition 5.0 2021-01
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Insulators for overhead lines with a nominal voltage above 1 000 V – Ceramic or
glass insulator units for AC systems – Characteristics of insulator units of the
cap and pin type




your local IEC member National Committee for further information.

IEC Central Office Tel.: +41 22 919 02 11
3, rue de
CH-1211 Geneva 20
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform IEC online collection - oc.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews. With a subscription you will always have
committee, …). It also gives information on projects, replaced access to up to date content tailored to your needs.
and withdrawn publications.
Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
The world's leading online dictionary on electrotechnology,
Stay up to date on all new IEC publications. Just Published
containing more than 22 000 terminological entries in English
details all new publications released. Available online and once
and French, with equivalent terms in 18 additional languages.
a month by email.
Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Customer Service Centre - webstore.iec.ch/csc

If you wish to give us your feedback on this publication or need
further assistance, please contact the Customer Service
.
IEC 60305
Edition 5.0 2021-01
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Insulators for overhead lines with a nominal voltage above 1 000 V – Ceramic or

glass insulator units for AC systems – Characteristics of insulator units of the

cap and pin type
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.080.10; 29.240.20 ISBN 978-2-8322-9270-9

– 2 – IEC 60305:2021 RLV © IEC 2021
CONTENTS
FOREWORD . 3
1 Scope and object . 5
2 Normative references . 5
3 Terms and definitions . 6
4 Mechanical and dimensional characteristics, dimensions and types . 6
5 Designation and marking with respect to shed profile . 6
6 Tolerances . 8
Bibliography . 16

Figure 1 – String insulator unit with ball and socket coupling .
Figure 2 – String insulator unit with clevis and tongue couplings .
Figure 1 – Typical "standard" profile . 7
Figure 2 – Typical "anti-fog" profile "P" . 7
Figure 3 – Typical "aerodynamic" profile "D" . 7
Figure 4 – Typical "two-alternating" profile "V" . 7
Figure 5 – Typical "three-alternating" profile "T" . 8
Figure 6 – String insulator unit of standard and anti-fog profile with ball and socket
coupling . 10
Figure 7 – String insulator unit of standard and anti-fog profile with clevis and tongue
coupling . 12
Figure 8 – String insulator unit of aerodynamic profile with ball and socket coupling . 13
Figure 9 – String insulator unit of two-alternating profile with ball and socket coupling . 13
Figure 10 – String insulator unit of three-alternating profile with ball and socket
coupling . 14

Table 1 – Specified values of mechanical and dimensional characteristics for string
insulator units with ball and socket couplings .
Table 2 – Specified values of mechanical and dimensional characteristics for string
insulator units with clevis and tongue couplings .
Table 1 – Specified values of mechanical and dimensional characteristics for string
insulator units of standard and anti-fog profile with ball and socket couplings . 11
Table 2 – Specified values of mechanical and dimensional characteristics for string
insulator units of standard and anti-fog profile with clevis and tongue couplings . 12
Table 3 – Specified values of mechanical and dimensional characteristics for string
insulator units of aerodynamic profile with ball and socket couplings . 13
Table 4 – Specified values of mechanical and dimensional characteristics for string
insulator units of two-alternating profile with ball and socket couplings . 14
Table 5 – Specified values of mechanical and dimensional characteristics for string
insulator units of three-alternating profile with ball and socket couplings . 15

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INSULATORS FOR OVERHEAD LINES WITH
A NOMINAL VOLTAGE ABOVE 1 000 V –
CERAMIC OR GLASS INSULATOR UNITS FOR AC SYSTEMS –
CHARACTERISTICS OF INSULATOR UNITS OF THE CAP AND PIN TYPE

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 itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
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.

This redline version of the official IEC Standard allows the user to identify the changes
made to the previous edition IEC 60305:1995. A vertical bar appears in the margin
wherever a change has been made. Additions are in green text, deletions are in
strikethrough red text.
– 4 – IEC 60305:2021 RLV © IEC 2021
International Standard IEC 60305 has been prepared by IEC technical committee 36:
Insulators.
This fifth edition cancels and replaces the fourth edition published in 1995. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) wording in Scope changed from "it is recommended" to "it is applicable";
b) new normative references added;
c) electromechanical or mechanical failing load in Clause 4 specified;
d) new figures added showing profiles;
e) Tables 1, 2, 3, 4 and 5 expanded to include more specified values.
The text of this International Standard is based on the following documents:
FDIS Report on voting
36/499/FDIS 36/501/RVD
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.
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.
INSULATORS FOR OVERHEAD LINES WITH
A NOMINAL VOLTAGE ABOVE 1 000 V –
CERAMIC OR GLASS INSULATOR UNITS FOR AC SYSTEMS –
CHARACTERISTICS OF INSULATOR UNITS OF THE CAP AND PIN TYPE

1 Scope and object
This International Standard applies to string insulator units of the cap and pin type with
insulating parts of ceramic material or glass, intended for AC overhead lines with a nominal
voltage greater than 1 000 V and a frequency not greater than 100 Hz. It also applies to
insulators of similar design used in substations.
This document applies to string insulator units of the cap and pin type either with ball and
socket couplings or with clevis and tongue couplings.
This document applies to string insulator units for use on overhead lines in clean areas and
polluted areas. For use in areas characterized by very heavy pollution levels and for other
particular or extreme environmental conditions, it may be necessary for certain dimensions to
be changed and insulator units having different creepage distances, spacing and forms may
be preferred (for example, flat profile, hemispherical etc.). Insulators for use on DC systems
may also need different dimensions. In any case, it is recommended applicable that the
standardized mechanical characteristics of this document and coupling sizes are retained.
The object of this document is to prescribe specified values for the mechanical characteristics
and for the main dimensions of string insulator units of the cap and pin type.
The power frequency, lightning impulse and puncture withstand voltages of string insulator
units are not specified in this document.
...

  • Relates Information
  • IEC 60300-3-7:1999

    IEC 60300-3-7:1999 - Dependability management - Part 3-7: Application guide - Reliability stress screening of electronic hardware Released:5/31/1999 Isbn:2831847974
    09-20
  • HD 571 S1:1990

    HD 571 S1:1998
    09-20
  • ISO 8130-4:1992

    ISO 8130-4:1992 - Coating powders
    09-20
  • HD 478.2.7 S1:1990

    HD 478.2.7 S1:2003
    09-19
  • ISO 8473:1988/Cor 1:1992

    ISO 8473:1988/Cor 1:1992 - Information processing systems — Data communications — Protocol for providing the connectionless-mode network service — Technical Corrigendum 1 Released:12/10/1992
    09-19
  • EN ISO 9013:2017/prA1

    EN ISO 9013:2017/oprA1:2024
    09-19
  • IEC 60118-6:1999

    IEC 60118-6:1999 - Hearing aids - Part 6: Characteristics of electrical input circuits for hearing aids Released:6/9/1999 Isbn:2831848075
    09-19
  • HD 280.3 S1:1990

    HD 280.3 S1:1999
    09-19
  • ISO 9832:1992

    ISO 9832:1992 - Animal and vegetable fats and oils -- Determination of residual technical hexane content
    09-19
  • EN 60188:1988/A1:1990

    EN 60188:1999/A1:1999
    09-18