Preface This is the fourth edition of CSA C22.2 No. 129, Neutral-supported cables, one of a series of Standards issued by the Canadian Standards Association under the Canadian Electrical Code, Part II. It supersedes the previous editions, published in 2005 under the title Neutral supported cables, and published in 1976 and 1963 under the title Neutral Supported Cable. Scope 1.1 This Standard specifies requirements for Type NS75 and NS90 neutral-supported cables for use on outdoor overhead electrical systems that (a) have nominal voltages of 600 V or less; and (b) are intended for installation in accordance with the Canadian Electrical Code, Part I. 1.2 Neutral-supported cables covered by this Standard consist of a maximum of five conductors (one, two, or three insulated phase conductors, a neutral conductor, and an optional insulated control/supply conductor). The conductors are insulated with polyethylene (PE) rated 75 °C or cross-linked polyethylene (XLPE) rated 75 or 90 °C. 1.3 Flame test requirements for neutral-supported cable insulations or coverings are also covered in this Standard, to the extent called for by the Canadian Electrical Code, Part I. 1.4 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 (nonmandatory) to define their application.