NATIONAL FOREWORD

This Indian Standard (Part 103) which is identical with IEC/TR 61869-103 : 2012 ‘Instrument transformers — Part 103: The use of instrument transformers for power quality measurement’ issued by the International Electrotechnical Commission (IEC) was adopted by the Bureau of Indian Standards on the recommendation of the Instrument Transformers Sectional Committee and approval of the Electrotechnical Division Council.

This standard is applicable to inductive and electronic instrument transformers for use with electrical measuring instruments for measurement and interpretation of results for power quality parameters in 50/60 Hz a.c. power supply systems. It gives guidance in the usage of HV instrument transformers for measuring power quality parameters, power frequency, magnitude of the supply voltage and current, flicker, supply voltage dips and swells, voltage interruptions, transient voltages, supply voltage unbalance, voltage and current harmonics and interharmonics, mains signalling on the supply voltage and rapid voltage changes.

The text of IEC Technical Report has been approved as suitable for publication as an Indian Standard without deviations. Certain conventions are, however, not identical to those used in Indian Standards. Attention is particularly drawn to the following:

a) Wherever the words ‘International Standard’ appear referring to this standard, they should be read as ‘Indian Standard’.

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