IEC 60044-1-2003 Instrument transformers - Part 1: Current transformers

Language: English, French
International Standard IEC 60044-1 has been prepared by IEC technical committee 38: Instrument transformers.
This consolidated version of IEC 60044-1 consists of the first edition (1996) [documents [documents 38/161/FDIS and 38/174/RVD, its amendment 1 (2000) [documents 38/245/FDIS and 38/257/RVD] and its amendment 2 (2002) [documents 38/285/FDIS and 38/289/RVD].
The technical content is therefore identical to the base edition and its amendments and has been prepared for user convenience.
It bears the edition number 1.2.
A vertical line in the margin shows where the base publication has been modified by amendments 1 and 2.
Annex A forms an integral part of this standard.
Annex B is for information only.
Scope
This part of IEC 60044 applies to newly manufactured current transformers for use with electrical measuring instruments and electrical protective devices at frequencies from 15 Hz to 100 Hz.
Although the requirements relate basically to transformers with separate windings, they are also applicable, where appropriate, to autotransformers.
Clause 11 covers the requirements and tests, in addition to those in clauses 3 to 10, that are necessary for current transformers for use with electrical measuring instruments.
Clause 12 covers the requirements and tests, in addition to those in clauses 3 to 10, that are necessary for current transformers for use with electrical protective relays, and in particular for forms of protection in which the prime requirement is the maintenance of accuracy up to several times the rated current.
For certain protective systems, where the current transformer characteristics are dependant on the overall design of the protective equipment (for example high-speed balanced systems and earth-fault protection in resonant earthed networks), additional requirements are given in clause 13 for class PR transformers and in clause 14 for class PX transformers.
Clause 13 covers the requirements and tests in addition to those in clauses 3 to 10 that are necessary for current transformers for use with electrical protective relays, and in particular for forms of protection in which the prime requirement is the absence of remanent flux.
Clause 14 covers the requirements and tests in addition to those in clauses 3 to 10 that are necessary for current transformers for use with electrical protective relays, and in particular for forms of protection for which knowledge of the transformer’s secondary excitation characteristic, secondary winding resistance, secondary burden resistance and turns ratio is sufficient to assess its performance in relation to the protective relay system with which it is to be used.
Current transformers intended for both measurement and protection shall comply with all the clauses of this standard.