Preface:

This is the first edition of CSA C61869-10, Instrument transformers — Part 10: Additional requirements for low-power passive current transformers, which is an adoption, with Canadian deviations, of the identically titled IEC (International Electrotechnical Commission) Standard 61869-10 (first edition, 2017-12). It replaces relevant parts of CAN/CSA-C60044-8:07 (adopted IEC 60044-8:2002), Instrument transformers — Part 8: Electronic current transformers. It is part of the CSA C61869 series of Standards on instrument transformers, which consists of adoptions with Canadian deviations of the IEC 61869 series of Standards.

This Standard is intended to be used in conjunction with CAN/CSA-C61869-1:14, Instrument transformers — Part 1: General requirements (adopted IEC 61869-1:2007, with Canadian deviations); and CSA C61869-6:20, Instrument transformers — Part 6: Additional general requirements for lowpower instrument transformers (adopted IEC 61869-6:2016, with Canadian deviations).

Requirements common to all instrument transformer types are grouped in CAN/CSA-C61869-1. Requirements specific to conventional instrument transformer types are grouped in CAN/CSA-C61869-2, CAN/CSA-C61869-3, CAN/CSA-C61869-4, and CAN/CSA-C61869-5. Those CSA Group Standards present many inherited Canadian deviations justified by the specific conditions, practices, and regulations in Canada.

Requirements common to low-power instrument transformers (LPIT) used for ac applications having rated frequencies from 15 Hz to 100 Hz covering MV, HV, and EHV or used for dc applications are grouped in CSA C61869-6.

The remaining Standards in the series state requirements for specific types of instrument transformers.

Canada has actively participated in the development of IEC 61869-10, in order to enforce specific Canadian conditions. It should be noted that Parts 6 to 13 of the IEC 61869 series specify the requirements for ac LPIT as well as the interfaces necessary to implement the LPIT into an integrated system for protection and measurement. Such a system uses a universal digital transmission protocol compatible with IEC 61850, and has a digital output. In order to ensure full interoperability, Canadian deviations in CSA C61869-10 are minimal.

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:

This part of IEC 61869 is a product standard and covers only additional requirements for low-power passive current transformers. The product standard for low-power passive current transformers comprises IEC 61869-1, together with IEC 61869-6 and this document with specific requirements.

This document is applicable to newly manufactured low-power passive current transformers with analogue output for use with electrical measuring instruments or electrical protective devices having a rated frequency from 15 Hz to 100 Hz.

This document covers low-power passive current transformers used for measurement or protection and multi-purpose low-power passive current transformers used for both measurement and protection.

Subclause 5.6.1001 covers the accuracy requirements that are necessary for low-power passive current transformers for use with electrical measuring instruments.

Subclause 5.6.1002 covers the accuracy requirements that are necessary for low-power passive current transformers for use with electrical protective relays, and particularly for forms of protection in which the prime requirement is to maintain the accuracy up to several times the rated current. If required, the transient accuracy of low-power passive current transformers during fault is also given in 5.6.1002.

Low-power passive current transformers have analogue voltage output only (for digital output or for technology using any kind of active electronic components refer to IEC 61869-82). Such low-power passive current transformers can include the secondary signal cable (transmitting cable). The principle of operation of derivative low-power passive current transformers using air-core coils (Rogowski coils) is given in Annex 10B and the principle of operation of proportional low-power passive current transformers using iron-core coils with integrated shunt is given in Annex 10C.