IEC 61109:2008 pdf download.Insulators for overhead lines – Composite suspension and tension insulators for a.c. systems with a nominal voltage greater than 1 000 V – Definitions, test methods and acceptance criteria.
IEC 61109:2008 applies to composite suspension/tension insulators consisting of a load-bearing cylindrical insulating solid core consisting of fibres-usually glass-in a resin- based matrix, a housing (outside the insulating core)made of polymeric material and end fittings permanently attached to the insulating core.
Composite insulators covered by this standard are intended for use as suspension/tension line insulators, but it should be noted that these insulators can occasionally be subjected to compression or bending, for example when used as phase-spacers.
This standard can be applied in part to hybrid composite insulators where the core is made of a homogeneous material ( porcelain, resin),see Clause 8.
The object of this standard is to
— define the terms used
— prescribe test methods
— prescribe acceptance criteria
This standard does not include requirements dealing with the choice of insulators for specific operating conditions.
4 Identification
In addition to the requirements of EC 62217, each insulator shall be marked with the SML.
It is recommended that each insulator be marked or labelled by the manufacturer to show that it has passed the routine mechanical test.
5 Environmental conditions
The normal environmental conditions to which insulators are submitted in service are defined IEC 62217.
6 Transport,storage and installation
In addition to the requirements of IEC 62217, information on handling of composite insulators can be found in CIGRE Technical Brochure 184 [7].During installation, or when used in non standard configurations, composite suspension insulators may be submitted to high torsion,
mpression or bending loads for which they are not designed Annex C gives guidance on catering for such loads.
7 Hybrid insulators
As stated in Clause 1 this standard can be applied in part to hybrid composite insulators where le core is made of a homogeneous material (porcelain, resin)。 In general, the load-time echanical tests and tests for core material are not applicable to porcelain cores. For such insulators, the purchaser and the manufacturer shall agree on the selection of tests to be used from this standard and from IEC 60383-1.
8 Tolerances
Unless otherwise agreed, a tolerance of
±(0,04*d+1,5) mm when d≤300mm
±(0,025*d+6)mm when d> 300 mm with a maximum tolerance of +50 mm
shall be allowed on all dimensions for which specific tolerances are not requested or given o the insulator drawing(d being the dimension in millimetres)
The measurement of creepage distances shall be related to the design dimensions and tolerances as determined from the insulator drawing, even if this dimension is greater than the value originally specified. When a minimum creepage is specified, the negative tolerance is also limited by this value.IEC 61109:2008 pdf download.