CSA C310-09 (R2019)

1.1 This Standard applies to open-type (fused and solid-blade) cutouts with a polymeric insulator structure component. These cutouts are intended for operation on alternating current distribution systems.

1.2 In some cases, specific types of construction are envisaged. This does not preclude the use of other types of construction, provided that the engineering representatives involved can demonstrate the safety and suitability of these alternatives.

1.3 In CSA Standards, “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.

1.4 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.