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 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 applicable that the standardized mechanical characteristics of this document and coupling sizes are retained. This fifth edition cancels and replaces the fourth edition published in 1995. This edition includes the following significant technical changes with respect to the previous edition:
- wording in Scope changed from "it is recommended" to "it is applicable";
- new normative references added;
- electromechanical or mechanical failing load in Clause 4 specified;
- new figures added showing profiles.

Isolateurs pour lignes aériennes de tension nominale supérieure à 1000 V - Eléments d'isolateurs en céramique ou en verre pour réseaux à tension alternative - Caractéristiques des éléments d'isolateurs du type capot et tige

L'IEC 60305:2021 s'applique aux éléments de chaînes d'isolateurs du type à capot et tige ayant des parties isolantes en matière céramique ou en verre et destinés aux lignes aériennes fonctionnant en courant alternatif à une tension nominale supérieure à 1 000 V et à une fréquence au plus égale à 100 Hz. Elle s'applique également aux isolateurs du même type utilisés dans les postes. Le présent document s'applique aux éléments de chaînes d'isolateurs du type à capot et tige soit avec assemblage à rotule, soit avec assemblage à chape et tenon. Le présent document s'applique aux éléments de chaînes d'isolateurs destinés aux lignes aériennes situées dans des régions polluées et non polluées. Pour les isolateurs destinés à être utilisés dans des régions très fortement polluées et dans d'autres conditions environnementales particulières ou extrêmes, il peut être nécessaire de modifier certaines dimensions et il peut être préférable d'utiliser des éléments d'isolateurs ayant des lignes de fuite, des pas et des formes différentes (par exemple, profil plat, hémisphérique, etc.). Les isolateurs destinés à être utilisés sur les réseaux à tension continue peuvent également nécessiter des dimensions différentes. Dans tous les cas, il est possible de retenir les caractéristiques mécaniques normalisées du présent document et les dimensions d'assemblage. Cette cinquième édition annule et remplace la quatrième édition parue en 1995. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- reformulation du domaine d'application: "il est recommandé d’utiliser" a été remplacé par "il est possible de retenir";
- ajout de nouvelles références normatives;
- spécification à l'Article 4 de la charge de rupture électromécanique ou mécanique;
- ajout de nouvelles figures représentant des profils.

General Information

Status
Published
Publication Date
10-Jan-2021
Technical Committee
Current Stage
PPUB - Publication issued
Completion Date
11-Jan-2021
Ref Project

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IEC 60305
Edition 5.0 2021-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
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
Isolateurs pour lignes aériennes de tension nominale supérieure a 1 000 V –
Éléments d’isolateurs en céramique ou en verre pour réseaux à tension
alternative – Caractéristiques des éléments d'isolateurs du type capot et tige
IEC 60305:2021-01(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 60305
Edition 5.0 2021-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
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
Isolateurs pour lignes aériennes de tension nominale supérieure a 1 000 V –
Éléments d’isolateurs en céramique ou en verre pour réseaux à tension
alternative – Caractéristiques des éléments d'isolateurs du type capot et tige
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.080.10; 29.240.20 ISBN 978-2-8322-9203-7

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – IEC 60305:2021 © IEC 2021
CONTENTS

FOREWORD ........................................................................................................................... 3

1 Scope .............................................................................................................................. 5

2 Normative references ...................................................................................................... 5

3 Terms and definitions ...................................................................................................... 5

4 Mechanical characteristics, dimensions and types ........................................................... 6

5 Designation and marking with respect to shed profile ...................................................... 6

6 Tolerances ...................................................................................................................... 8

Bibliography .......................................................................................................................... 14

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 .................................................................................................................................. 8

Figure 7 – String insulator unit of standard and anti-fog profile with clevis and tongue

coupling ................................................................................................................................ 10

Figure 8 – String insulator unit of aerodynamic profile with ball and socket coupling ............. 11

Figure 9 – String insulator unit of two-alternating profile with ball and socket coupling .......... 11

Figure 10 – String insulator unit of three-alternating profile with ball and socket

coupling ................................................................................................................................ 12

Table 1 – Specified values of mechanical and dimensional characteristics for string

insulator units of standard and anti-fog profile with ball and socket couplings ......................... 9

Table 2 – Specified values of mechanical and dimensional characteristics for string

insulator units of standard and anti-fog profile with clevis and tongue couplings ................... 10

Table 3 – Specified values of mechanical and dimensional characteristics for string

insulator units of aerodynamic profile with ball and socket couplings .................................... 11

Table 4 – Specified values of mechanical and dimensional characteristics for string

insulator units of two-alternating profile with ball and socket couplings ................................. 12

Table 5 – Specified values of mechanical and dimensional characteristics for string

insulator units of three-alternating profile with ball and socket couplings ............................... 13

---------------------- Page: 4 ----------------------
IEC 60305:2021 © IEC 2021 – 3 –
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

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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 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.
---------------------- Page: 5 ----------------------
– 4 – IEC 60305:2021 © IEC 2021
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.
---------------------- Page: 6 ----------------------
IEC 60305:2021 © IEC 2021 – 5 –
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

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 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. IEC 60383-1 gives the electrical characteristics which

define string insulator units; their values are agreed between purchaser and manufacturer.

Ball and socket couplings are covered by IEC 60120, clevis and tongue couplings by

IEC 60471.
NOTE For the definition of site pollution severity see IEC TS 60815-1.
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 60383-1, Insulators for overhead lines with a nominal voltage above 1000 V – Part 1:

Ceramic or glass insulator units for AC systems – Definitions, test methods and acceptance

criteria
3 Terms and definitions
No terms and definitions are listed in this document.
---------------------- Page: 7 ----------------------
– 6 – IEC 60305:2021 © IEC 2021

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
4 Mechanical characteristics, dimensions and types

String insulator units of the cap and pin type are standardized by the following specified

characteristics:

– Specified electromechanical or mechanical failing load (SFL) according to IEC 60383-1;

– maximum nominal diameter of the insulating part;
– nominal spacing;
– minimum nominal creepage distance;
– standard coupling.

The corresponding values are indicated in Table 1, Table 2, Table 3, Table 4 and Table 5.

NOTE 1 The following points merit attention for insulators for use in polluted areas:

a) even if the creepage distance is the same, the withstand voltage characteristics may change with shed shape of

the insulators;

b) even if the string length is the same, the withstand voltage characteristics may decrease with increasing

insulator strength due to the lower efficiency of creepage distance for a larger average diameter.

NOTE 2 IEC 60815 gives details on the important parameters of shed profiles for antipollution insulators.

5 Designation and marking with respect to shed profile

Insulators are designated in Table 1, Table 2, Table 3, Table 4 and Table 5 by the letter U

followed by a number indicating the specified electromechanical or mechanical failing load in

kilonewtons.

The letter B or C which follows specifies a ball and socket or clevis and tongue, respectively.

The following letter S or L, if present, specifies a short or long spacing.

The letter P, D, V, or T present for "anti-fog" profile, "aerodynamic" profile, "two-alternating"

profile, or "three-alternating" profile, as shown in Figure 1, Figure 2, Figure 3,Figure 4 and

Figure 5, respectively.

IEC 60383-1 specifies that insulators shall be marked with the specified electromechanical or

mechanical failing load. This load may be indicated by using the first part of the designation

given in the first column of Table 1, Table 2, Table 3, Table 4 and Table 5: For instance, the

insulator may be marked U 160 for the units U 160 BS, U 160 BL and U 160 BLP.
---------------------- Page: 8 ----------------------
IEC 60305:2021 © IEC 2021 – 7 –
Figure 1 – Typical "standard" profile
Figure 2 – Typical "anti-fog" profile "P"
Figure 3 – Typical "aerodynamic" profile "D"
Figure 4 – Typical "two-alternating" profile "V"
---------------------- Page: 9 ----------------------
– 8 – IEC 60305:2021 © IEC 2021
Figure 5 – Typical "three-alternating" profile "T"
6 Tolerances

Except for nominal spacing, tolerances for dimensions indicated in IEC 60383-1 are

applicable to all nominal values including maximum nominal diameter and minimum nominal

creepage distance values given in Table 1, Table 2, Table 3, Table 4 and Table 5.

Diagram of Table 1, Table 2, Table 3, Table 4 and Table 5 is shown in Figure 6, Figure 7,

Figure 8, Figure 9 and Figure 10, respectively.
Nominal spacing tolerance shall be:
± (0,03 P + 0,3) mm
P being spacing expressed in millimetres.
Figure 6 – String insulator unit of standard and anti-fog
profile with ball and socket coupling
---------------------- Page: 10 ----------------------
IEC 60305:2021 © IEC 2021 – 9 –

Table 1 – Specified values of mechanical and dimensional characteristics for string

insulator units of standard and anti-fog profile with ball and socket couplings
Designation Specified Maximum Nominal Minimum Standard
electromechanical nominal spacing nominal coupling
or mechanical diameter of the creepage according to
failing load insulating part distance IEC 60120
kN D P mm d1
mm mm
U 40 B 40 175 110 190 11
U 40 BP 40 210 110 295 11
U 70 BS 70 255 127 295 16
U 70 BL 70 255 146 295 16
U 70 BLP 70 280 146 440 16
U 100 BS 100 255 127 295 16
U 100 BL 100 255 146 295 16
U 100 BLP 100 280 146 440 16
U 120 B 120 255 146 295 16
U 120 BP 120 280 146 440 16
U 160 BS 160 280 146 315 20
U 160 BSP 160 330 146 440 20
U 160 BL 160 280 170 340 20
U 160 BLP 160 330 170 525 20
U 210 B 210 300 170 370 20
U 210 BP 210 330 170 525 20
U 300 B 300 330 195 390 24
U 300 BP 300 400 195 590 24
U 400 B 400 380 205 525 28
U 420 B 420 380 205 525 28
U 530 B 530 380 240 600 32
U 550 B 550 380 240 600 32
U 700 B 700 430 280 600 36
U 840 B 840 430 300 600 40
---------------------- Page: 11 ----------------------
– 10 – IEC 60305:2021 © IEC 2021
Figure 7 – String insulator unit of standard and anti-fog profile
with clevis and tongue coupling

Table 2 – Specified values of mechanical and dimensional characteristics for string

insulator units of standard and anti-fog profile with clevis and tongue couplings

Designation Specified Maximum Nominal Minimum Standard
electromechanical nominal spacing nominal coupling
or mechanical diameter of the creepage according to
failing load insulating part distance IEC 60471
kN D P mm
mm mm
U 40 C 40 190 140 200 16 C
U 70 C 70 255 146 295 16 C
U 70 CP 70 280 146 440 16 C
U 100 C 100 255 146 295 16 C
U 100 CP 100 280 146 440 16 C
U 120 C 120 255 146 295 16 C
U 120 CP 120 280 146 440 16 C
U 160 C 160 280 170 340 19 C
U 160 CP 160 330 170 525 19 C
U 210 C 210 300 178 370 22 C
U 210 CP 210 330 178 525 22 C

NOTE Insulators having an electromechanical or mechanical failing load exceeding 210 kN are not specified. If

necessary, the insulators with ball and socket coupling defined in Table 1 shall preferably be used.

---------------------- Page: 12 ----------------------
IEC 60305:2021 © IEC 2021 – 11 –

Figure 8 – String insulator unit of aerodynamic profile with ball and socket coupling

Table 3 – Specified values of mechanical and dimensional characteristics for string

insulator units of aerodynamic profile with ball and socket couplings
Designation Specified Maximum Nominal Minimum Standard
electromechanical nominal spacing nominal coupling
or mechanical diameter of the creepage according to
failing load insulating part distance IEC 60120
kN D P
mm mm mm
U 70 BSD 70 380 127 305 16
U 70 BLD 70 380 146 305 16
U 120 BSD 120 380 127 295 16
U 120 BLD 120 380 146 295 16
U 160 BD 160 425 146 375 20
U 210 BD 210 425 170 375 20

Figure 9 – String insulator unit of two-alternating profile with ball and socket coupling

---------------------- Page: 13 ----------------------
– 12 – IEC 60305:2021 © IEC 2021

Table 4 – Specified values of mechanical and dimensional characteristics for string

insulator units of two-alternating profile with ball and socket couplings
Designation Specified Maximum Nominal Minimum Standard
electromechanical nominal spacing nominal coupling
or mechanical diameter of the creepage according to
failing load insulating part distance IEC 60120
kN D P
mm mm mm
U 70 BSV 70 280 146 450 16
U 70 BLV 70 280 160 450 16
U 120 BSV 120 280 146 450 16
U 120 BLV 120 280 160 450 16
U 160 BSV 160 290 155 450 20
U 160 BV 160 290 160 450 20
U 160 BLV 160 355 170 450 20
U 210 BV 210 355 170 450 20
U 240 BV 240 300 170 450 24
U 300 BV 300 360 195 485 24
U 400 BV 400 400 205 555 28
U 420 BV 420 400 205 555 28
U 530 BV 530 420 240 600 32
U 550 BV 550 420 240 600 32
Figure 10 – String insulator unit of three-alternating
profile with ball and socket coupling
---------------------- Page: 14 ----------------------
IEC 60305:2021 © IEC 2021 – 13 –

Table 5 – Specified values of mechanical and dimensional characteristics for string

insulator units of three-alternating profile with ball and socket couplings
Designation Specified Maximum Nominal Minimum Standard
electromechanical nominal spacing nominal coupling
or mechanical diameter of the creepage according to
failing load insulating part distance IEC 60120
kN D P
mm mm mm
U 70 BT 70 320 155 550 16
U 120 BT 120 320 155 550 16
U 160 BST 160 325 155 545 20
U 160 BT 160 325 160 545 20
U 160 BLT 160 325 170 545 20
U 210 BT 210 325 170 545 20
U 240 BT 240 325 170 545 24
U 300 BT 300 400 195 550 24
U 400 BT 400 400 205 635 28
U 420 BT 420 400 205 635 28
U 530 BT 530 400 240 635 32
U 550 BT 550 400 240 635 32
---------------------- Page: 15 ----------------------
– 14 – IEC 60305:2021 © IEC 2021
Bibliography

[1] IEC 60120:2020, Ball and socket couplings of string insulator units – Dimensions

[2] IEC 60471:2020, Clevis and tongue couplings of string insulator units – Dimensions

[3] IEC TS 60815-1:2008, Selection and dimensioning of high-voltage insulators intended

for use in polluted conditions – Part 1: Definitions, information and general principles

[4] IEC TS 60815-2:2008, Selection and dimensioning of high-voltage insulators intended

for use in polluted conditions – Part 2: Ceramic and glass insulators for AC systems

_____________
---------------------- Page: 16 ----------------------
– 16 – IEC 60305:2021 © IEC 2021
SOMMAIRE

AVANT-PROPOS .................................................................................................................. 17

1 Domaine d’application ................................................................................................... 19

2 Références normatives .................................................................................................. 19

3 Termes et définitions ..................................................................................................... 20

4 Caractéristiques mécaniques, dimensions et types ........................................................ 20

5 Désignation et marquage en rapport avec le profil d'ailette ............................................ 20

6 Tolérances .................................................................................................................... 22

Bibliographie ......................................................................................................................... 28

Figure 1 – Profil type "normal" .............................................................................................. 21

Figure 2 – Profil type "pollution" "P" ...................................................................................... 21

Figure 3 – Profil type "aérodynamique" "D" ........................................................................... 21

Figure 4 – Profil type "à deux ailettes externes" "V" .............................................................. 21

Figure 5 – Profil type "à trois ailettes externes" "T" ............................................................... 22

Figure 6 – Élément de chaîne d'isolateurs de profil normal et pollution avec

assemblage à rotule.............................................................................................................. 22

Figure 7 – Élément de chaîne d'isolateurs de profil normal et pollution avec

assemblage à chape et tenon ............................................................................................... 24

Figure 8 – Élément de chaîne d'isolateurs de profil aérodynamique avec assemblage à

rotule .................................................................................................................................... 25

Figure 9 – Élément de chaîne d'isolateurs de profil à deux ailettes externes avec

assemblage à rotule.............................................................................................................. 26

Figure 10 – Élément de chaîne d'isolateurs de profil à trois ailettes externes avec

assemblage à rotule.............................................................................................................. 27

Tableau 1 – Valeurs spécifiées des caractéristiques mécaniques et dimensionnelles

pour les éléments de chaînes d'isolateurs de profil normal et pollution avec

assemblages à rotule ............................................................................................................ 23

Tableau 2 – Valeurs spécifiées des caractéristiques mécaniques et dimensionnelles

pour les éléments d
...

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