IEC 60076-10-1:2016

FOREWORD
1 Scope
2 Normative references
3 Basic physics of sound
4 Sources and characteristics of transformer
  and reactor sound
5 Measurement principles
6 Practical aspects of making sound measurements
7 Difference between factory tests and field sound level
  measurements
Annex A (informative) - Sound level built up due to
        harmonic currents in windings
Bibliography

IEC 60076-10-1:2016 provides supporting information to help both manufacturers and purchasers to apply the measurement techniques described in IEC 60076-10. Besides the introduction of some basic acoustics, the sources and characteristics of transformer and reactor sound are described. Practical guidance on making measurements is given, and factors influencing the accuracy of the methods are discussed. This application guide also indicates why values measured in the factory may differ from those measured in service. This application guide is applicable to transformers and reactors together with their associated cooling auxiliaries. This edition includes the following significant technical changes with respect to the previous edition:
a) extended information on sound fields provided;
b) effect of current harmonics in windings enfolded;
c) updated information on measuring methods sound pressure and sound intensity given;
d) supporting information on measuring procedures walk-around and point-by-point given;
e) clarification of A-weighting provided;
f) new information on frequency bands given;
g) background information on measurement distance provided;
h) new annex on sound-built up due to harmonic currents in windings introduced.

This publication is to be read in conjunction with IEC 60076-10:2016.