AS 61466.1:2020 pdf Composite string insulator units for overhead lines with a nominal voltage greater than 1 000 V
1 Scope
This part of IEC 61 466 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 1 00 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. NOTE 1 General definitions and methods of testing are given in IEC 61 1 09. NOTE 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 coordination of dimensions of the end- fittings with the strength classes is specified in Clause 7.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document
and are indispensable for its application. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 601 20:1 984, Dimensions of ball and socket couplings of string insulator units
IEC 60471 :1 977, Dimensions of clevis and tongue couplings of string insulator units
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 eleven standard SML classes designated for use together with 1 0
different series of couplings as follows.
– Two different standard series of ball couplings, one according to IEC 601 20 and one,
type N, as shown in Annex A of this standard.
– Two different standard series of socket couplings, one according to IEC 601 20 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 60471
and one, type N, as shown in Annex B of this standard.
– Two different standard series of clevis couplings, one, type L, according to IEC 60471 ,
and one, type N, as shown in Annex B of this standard
– One standard series of Y clevis couplings, as shown in Annex C of this standard.
– One 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 on 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 61466.1:2020 pdf Composite string insulator units for overhead lines with a nominal voltage greater than 1 000 V
