IEC 61952-1:2019 pdf download

IEC 61952-1:2019 pdf download.Insulators for overhead lines – Composite line post insulators for AC systems with a nominal voltage greater than 1 000 V
1 Scope
This part of IEC 61 952 is applicable to composite line post insulators for AC overhead lines with a nominal voltage greater than 1 000 V and a frequency not greater than 1 00 Hz. It also applies to line post insulators of similar design used in substations or on electric traction lines. This document applies to line post insulators of composite type, generally with metallic couplings, with and without a base plate. It also applies to such insulators when used in complex structures. It does not apply to hollow insulators adapted for use as line post insulators. The object of this document is to specify the main dimensions of the couplings to be used on the composite line post insulators 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 specifies a standard designation system for composite line post insulators.
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 60050-471 , International Electrotechnical Vocabulary – Part 471: Insulators IEC 60071 -1 , Insulation co-ordination – Part 1: Definitions, principles and rules IEC 61 952:2008, Insulators for overhead lines – Composite line post insulators for A.C. systems with a nominal voltage greater than 1 000 V – Definitions, test methods and acceptance criteria
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-471 and IEC 61 952 and the following apply. 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 3.1 coupling part of the end fitting designed for attachment of the composite line post insulator to line equipment, supporting structures, base plates or other insulators 3.2 core diameter nominal diameter of the load-bearing core of the insulator 3.3 line end fitting fitting at the end of the line post insulator to which the conductor or other live equipment is to be attached Note 1 to entry: Line end fitting can be from metal or insulating material. 3.4 base end fitting fitting at the end intended to be attached to the supporting structure, either directly or by an intermediate base or plate 3.5 base intermediate hardware to allow attachment of the line post insulator to the supporting structure 3.6 reference cantilever load RCL North American practise for defining maximum admissible working load 3.7 maximum design cantilever load MDCL load level above which damage to the core begins to occur and which is the ultimate limit for service loads. This value and direction of the load are specified by the manufacturer 3.8 minimum lightning impulse withstand voltage BIL impulse voltage having a front time of 1 ,2 µs and a time to half-value of 50 µsCore diameter does not form part of the specified characteristics of composite line post insulators; however some fitting dimensions depend on the core diameter. Common nominal core diameters (in mm) are as follows: 37, 40, 45, 51 , 63, 76, 88, 1 02, 1 20, 1 30. Creepage distance does not form part of the specified characteristics of composite line post insulators; however it may be included in the insulator designation. All dimensions are expressed in millimetres. The dimensions apply to the finished product after any surface treatment. 4.2 Maximum design cantilever load (MDCL) and specified cantilever load (SCL) Each insulator is characterised by the MDCL and SCL as defined in IEC 61 952. The manufacturer’s recommended working cantilever load may be listed as the MDCL or the reference cantilever load (RCL) and may be as much as 50 % of the SCL.