AC suspension insulators

1.1
This Standard applies to wet-process porcelain and toughened glass suspension-type insulators used on ac overhead power lines with a nominal voltage greater than 1000 V and a frequency not greater than 100 Hz.

This Standard applies to single insulator units only and does not apply to long rod insulators.

1.2
This Standard specifies provisions for

a) the mechanical, electrical, and dimensional characteristics of insulators and the conditions under which the specified values of these characteristics are verified; and
b) test methods and acceptance criteria.

1.3
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 (non-mandatory) to define their application.