CSA C2.2:25

Preface This is the second edition of CSA C2.2, Pole-mounted, single-phase distribution transformers for electric utilities . It supersedes the previous edition published in 2006. This edition includes requirements for single-phase, single-bushing, 60 Hz distribution transformers suitable for direct pole mounting and designed for operation on an effectively grounded wye system, Type ONAN, rated at 167 kVA or below, up to 34.5 kV system nominal voltage. Changes to this edition include updates to various clauses, tables, figures, and annexes to reflect minimum industry requirements. This Standard specifies the requirements for pole-mounted, single-phase distribution transformers rated up to and including 167 kVA intended primarily for operation by electric utilities. The operation of transformers complying with this Standard by other than an electric utility can be subject to additional requirements by the electrical inspection authority having jurisdiction. CSA Group acknowledges that the development of this Standard was made possible, in part, by the financial support of Alectra Utilities, Electricity Canada, EPCOR, Fortis Alberta, FortisBC, Hydro One, Hydro-Québec, IFD Corp., K-Line Insulators Ltd., Maritime Electric, NB Power, Newfoundland and Labrador Hydro, Newfoundland Power, Nova Scotia Power, S&C Electric Canada Ltd., Schneider Electric Canada Inc., Toronto Hydro, and Utilities Standards Forum. This Standard was prepared by the Subcommittee on Overhead and Pad-Mounted Distribution Transformers, under the jurisdiction of the Technical Committee on Distribution Transformers and the Strategic Steering Committee on Power Engineering and Electromagnetic Compatibility, and has been formally approved by the Technical Committee. This Standard has been developed in compliance with Standards Council of Canada requirements for National Standards of Canada. It has been published as a National Standard of Canada by CSA Group. Scope 1.1 General This Standard specifies the requirements for distribution transformers intended primarily for operation by electric utilities. Note: The operation of transformers complying with this Standard by other than an electric utility might be subject to additional requirements by the electrical inspection authority having jurisdiction. 1.2 Ratings This Standard applies to single-phase, single-bushing, 60 Hz distribution transformers suitable for direct pole mounting and designed for operation on an effectively grounded wye system, type ONAN, rated at 167 kVA or below, up to 34.5 kV system nominal voltage. 1.3 Performance characteristics This Standard includes voltage ratings, kVA ratings, certain mechanical characteristics, and test procedures. It also includes the following performance characteristics: a) energy efficiency (in accordance with CSA C802.1); b) temperature rise; c) loading capabilities; d) sound level; and e) radio influence voltage (RIV). 1.4 Self-protected transformers Requirements for self-protected transformers are not covered by this Standard. 1.5 Exclusions This Standard does not apply to auto-, testing, dry-type, welding, furnace, rectifier, network, pad-mounted, subway-type, or special-purpose transformers, or to step-voltage regulators. 1.6 Terminology 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.