IS 1885 : Part 27 : 2008 /IEC 60050-551 : 1998 Electrotechnical Vocabulary - Part 27 : Power Electronics

National Foreword

This Indian Standard (Part 27) (Third Revision) which is identical with IEC 60050-551 : 1998lnternationalElectrotechnical Vocabulary - Part 551 : Power electronics issued by the InternationalElectrotechnical Commission (IEC) was adopted by the Bureau of Indian Standards on therecommendation of the Basic Electrotechnical Standards Sectional Committee and approval of the Electrotechnical Division Council.

This standard was first published in 1969. The first revision was published in 1985 and the secondrevision was published in 1993. The third revision has been undertaken in order to bring it in line with thelatest IEC publication IEC 60050-551 : 1998.

The text of IEC Standard has been approved as suitable for publication as an Indian Standard withoutdeviations. Certain conventions are, however, not identical to those used in Indian Standards, Attentionis particularly drawn to the following:

a) Wherever the words International Standard appear referring to this standard, they shouldbe read as Indian Standard.

b) Comma (,) has been used as a decimal marker while in Indian Standards, the currentpractice is to use a point (.) as the decimal marker.

For the purpose of deciding whether a particular requirement of this standard is complied with, thefinal value, observed or calculated expressing the result of a test or analysis, shall be rounded off inaccordance with IS 2 : 1960 Rules for rounding off numerical values (revised). The number of significantplaces retained in the rounded off value should be the same as that of the specified value in thisstandard.