EN 61466-1:1997

SLOVENSKI STANDARD
01-november-1997
Composite string insulator units for overhead lines with nominal voltage greater
than 1 kV - Part 1: Standard strenght classes and fittings (IEC 61644-1:1997)
Composite string insulator units for overhead lines with a nominal voltage greater than 1
kV -- Part 1: Standard strength classes and end fittings
Verbund-Kettenisolatoren für Freileitungen mit einer Nennspannung über 1kV -- Teil 1:
Genormte Festigkeitsklassen und Endarmaturen
Isolateurs composites pour lignes aériennes de tension nominale supérieure à 1 kV --
Partie 1: Classes mécaniques et accrochages d'extrémité standards
Ta slovenski standard je istoveten z: EN 61466-1:1997
ICS:
29.080.10 Izolatorji Insulators
29.240.20 Daljnovodi Power transmission and
distribution lines
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

NORME
CEI
INTERNATIONALE
IEC
61466-1
INTERNATIONAL
Première édition
STANDARD
First edition
1997-02
Isolateurs composites pour lignes aériennes
de tension nominale supérieure à 1 000 V –
Partie 1:
Classes mécaniques et accrochages
d’extrémité standards
Composite string insulator units for
overhead lines with a nominal voltage
greater than 1 000 V –
Part 1:
Standard strength classes and end fittings
 IEC 1997 Droits de reproduction réservés  Copyright - all rights reserved
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Pour prix, voir catalogue en vigueur
For price, see current catalogue

61466-1 © IEC:1997 – 3 –
CONTENTS
Page
FOREWORD . 5
Clause
1 Scope . 7
2 Normative references. 7
3 Mechanical and dimensional characteristics . 9
4 Plan of the standard. 9
5 Insulator designation. 9
6 Marking . 11
7 Composite insulator units. 11
Annexes
A Ball and socket couplings, N series . 15
B Clevis and tongue couplings, N series . 33
C Y-clevis couplings . 37
D Eye couplings. 41

61466-1 © IEC:1997 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
–––––––––
COMPOSITE STRING INSULATOR UNITS FOR OVERHEAD LINES
WITH A NOMINAL VOLTAGE GREATER THAN 1 000 V –
Part 1: Standard strength classes and end fittings
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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. The 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 the 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 National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical reports or guides and they are accepted by the National Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61466-1 has been prepared by subcommittee 36B: Insulators for
overhead lines, of IEC technical committee 36: Insulators.
The text of this standard is based on the following documents:
FDIS Report on voting
36B/158/FDIS 36B/164/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.
Annexes A, B, C and D form an integral part of this standard.

61466-1 © IEC:1997 – 7 –
COMPOSITE STRING INSULATOR UNITS FOR OVERHEAD LINES
WITH A NOMINAL VOLTAGE GREATER THAN 1 000 V –
Part 1: Standard strength classes and end fittings
1 Scope
This part of IEC 61466 is applicable to composite string insulator units for a.c. 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 or on electric traction lines.
This standard applies to string insulator units of composite type with ball, socket, tongue,
clevis, Y-clevis or eye couplings, or a combination thereof.
The object of this standard is to prescribe specified values for the mechanical characteristics of
the composite string insulator units and define the main dimensions of the couplings to be used
on the composite string insulator units in order to permit the assembly of insulators or fittings
supplied by different manufacturers and to allow, whenever practical, interchangeability with
existing installations.
It also defines a standard designation system for composite string insulator units.
NOTES
1 General definitions and methods of testing are given in IEC 1109.
2 Only the dimensions necessary for assembly of the couplings are dealt with in this International Standard.
Properties of material and working loads are not specified. The co-ordination of dimensions of the end-fittings
with the strength classes is specified in Clause 7.
2 Normative references
The following normative documents contain provisions which, through reference in the text,
constitute provisions of this part of IEC 61466. At the time of publication, the editions indicated
were valid. All normative documents are subjected to revision, and parties to agreements
based on this part of IEC 61466 are encouraged to investigate the possibility of applying the
most recent edition of the normative documents indicated below. Members of IEC and ISO
maintain registers of currently valid International Standards.
IEC 120: 1984, Dimensions of ball and socket couplings of string insulator units
IEC 471: 1977, Dimensions of clevis and tongue couplings of string insulator units
IEC 1109: 1992, Composite insulators for a.c. overhead lines with a nominal voltage greater
than 1 000 V – Definitions, test methods and acceptance criteria

61466-1 © IEC:1997 – 9 –
3 Mechanical and dimensional characteristics
Composite string insulator units are standardized by the following specified characteristics:
– specified mechanical load (SML);
– standard couplings.
All dimensions are expressed in millimetres.
The dimensions apply to the finished product after any surface treatment.
4 Plan of the standard
This standard includes nine standard SML classes designated for use together with 10 different
series of couplings as follows.
– Two different standard series of ball couplings, one according to IEC 120 and one,
type N, as shown in annex A of this standard.
– Two different standard series of socket couplings, one according to IEC 120 and one,
type N, as shown in annex A of this standard.
– Two different standard series of tongue couplings, one, type L, according to IEC 471 and
one, type N, as shown in annex B of this standard.
– Three different standard series of clevis couplings, one, Type L, according to IEC 471,
one, type N, as shown in annex B of this standard and one, type Y, as shown in annex C of
this standard.
– One type of standard series of eye couplings as shown in annex D of this standard.
5 Insulator designation
Insulators are designated in table 1 by letter CS followed by a number indicating the specified
mechanical load (SML) in kilonewtons. The letter B, S, T, C, Y or E or a combination thereof
which follows specifies a ball, socket, tongue, clevis, Y-clevis or eye coupling, see figure 1. The
following figures specify the size of the coupling. When a combination of couplings are used,
the first letter shall always express the coupling in the upper end of the insulator. The upper
end of the insulator is defined in relation to the slope of the sheds. In the case of symmetrical
profile of the sheds any order of the letters is acceptable.
As examples, possible designations could be:
CS 120 S16 B16 indicates a composite insulator having a SML equal to 120 kN, a socket
coupling according to IEC 120, size 16, at the upper end and a ball coupling according to
IEC 120, size 16, at the other end.
CS 120 C19N T19N indicates a composite insulator having a SML equal to 120 kN, a clevis
coupling according to annex B, size 19N, at the upper end and a tongue coupling according to
annex B, size 19N, at the other end.
NOTE – Fittings of the same type conforming to different standards (e.g. IEC 120 and annex A of this standard)
should be avoided on the same insulator.

61466-1 © IEC:1997 – 11 –
6 Marking
Each insulator shall be clearly and indelibly marked with the name or trademark of the
manufacturer, the year of manufacture, the specified mechanical load (SML) and a means
permitting identification of each of the component parts.
7 Composite insulator units
The values of the specified mechanical loads (SML) for composite string insulators together
with corresponding coupling sizes are given in table 1.
The designation letters of the different designs of couplings which may be used in any
combination are shown in figure 1.

61466-1 © IEC:1997 – 13 –
BS T YE
C
Upper end
BS T C YE
Figure 1 – Designation letters of couplings
Table 1 – Insulator designation
Specified
Designation mechanical Ball and socket Clevis and tongue Y-clevis Eye
load
(SML)
IEC 120 annex A IEC 471 annex B annex C annex D
size size size size size size
CS 40 40 11 – – – – –
CS 70 70 16 16N 13L 16N 16 (19) 17 (24)
CS 100 100 16 16N 16L 16N (19N) 19 24
CS 120 120 16 (20) 18N 16L 16N (19N) 19 24
CS 160 160 20 22N 19L 19N (22N) 22 25
CS 210 210 20 (24) 22N (19L) 22L 22N 22 25
CS 300 300 24 – 25L – – –
CS 400 400 28 – 28L – – –
CS 530 530 32 – 32L – – –
NOTE – Non-preferred coupling sizes in brackets

61466-1 © IEC:1997 – 15 –
Annex A
(normative)
Ball and socket couplings, N series
A.1 General
This annex applies to the couplings of composite string insulator units.
This annex defines the dimensions of a standardized series of ball and socket couplings, which
permit the replacement of existing insulator sets in accordance with North American practice,
and permits the assembly of composite insulator units and fittings supplied by different
manufacturers.
A.2 Dimensions
The dimensions for the ball and socket couplings are expressed by dimensions for the GO and
NOT GO gauges, see figures A.1 to A.7.
All dimensions indicated in the tables A.1 to A.7 are given in millimetres and refer to the
finished product after surface treatment such as, for instance, hot dip galvanizing.
The outside dimensions of the socket have not been fixed, since they depend on the
mechanical characteristics of the material used. Only the dimensions necessary for assembly
of the couplings are dealt with in this standard.
In general, the ball is made of forged steel and the socket is made of malleable or ductile cast
iron or forged steel. However, other materials may be used if they have mechanical
characteristics corresponding to those given in table 1 of this standard.
NOTE – Dimensions are converted from inches.
A.3 Constructional features of the gauges
The choice of material, the hardness, the surface fin
...