Composite station post insulators This
This Standard specifies the electrical, mechanical, dimensional characteristics, test methods, and acceptance criteria for composite station post insulators for outdoor service, operating at nominal voltages greater than 1000 V and frequency not greater than 100 Hz. Station post insulators are mainly used as support or operating elements in switching equipment, or as bus bar or other equipment supports. Station post insulators are subjected to tensile, cantilever, torsional, and compressive loads.
This Standard deals with composite insulators having a solid core with metal fittings and housing with sheds. The core has resin-impregnated glass fibres. The housing with sheds consists of elastomers (e.g., silicone, ethylene propylene). The metal fittings are aluminum, steel, or iron.
In this Standard, “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the Standard; “should” is used to express a recommendation or that which is advised but not required; and “may” is used to express an option or that which is permissible within the limits of the Standard.
Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.
Notes to tables and figures are considered part of the table or figure and may be written as requirements.
Annexes are designated normative (mandatory) or informative (nonmandatory) to define their application.
The values given in SI units are the units of record for the purposes of this Standard. The values given in parentheses are for information and comparison only.