Toward a realistic estimate of octave band sound levels for electric transformers

Authors

  • Robert D. Stevens HGC Engineering, 2000 Argentia Road, Mississauga, ON L5N 1P7, Canada
  • Chris Hung HGC Engineering, 2000 Argentia Road, Mississauga, ON L5N 1P7, Canada

Keywords:

Electric transformers, Frequency bands, Manufacture, Textbooks, Measured data, Octave bands, Ontario, Prediction equations, Sound emission, Sound level, Whole body

Abstract

The typical starting point, when evaluating the sound emissions of a proposed transformer, is to obtain the manufacturer's sound level data or develop an estimate using generic prediction equations from a published textbook. If sound level information is available from the transformer manufacturer - whether measured or estimated - it is usually given only in terms of an overall A-weighted ("dBA") value. So, for detailed analysis in octave frequency bands, textbook information is still usually required, in terms of the spectral weightings needed to apportion the single dBA level into its component octave band sound levels. Unfortunately, the information in the published reference texts varies enormously with regard to the suggested spectral weighting corrections. The corrections in some texts are internally inconsistent, and the discrepancy among different texts (even those which cite the same primary references) is severe enough to call the whole body of data into question. This paper enumerates the inconsistencies and discrepancies within and among several commonly used acoustical engineering text books and compares the textbook levels to a wide body of data collected at numerous outdoor transformer installations throughout Ontario. Suggestions are provided for realistic spectral weightings and sound level estimates for transformers, on the basis of the measured data.

Additional Files

Published

2010-03-01

How to Cite

1.
Stevens RD, Hung C. Toward a realistic estimate of octave band sound levels for electric transformers. Canadian Acoustics [Internet]. 2010 Mar. 1 [cited 2026 May 14];38(1):13-8. Available from: https://jcaa.caa-aca.ca/index.php/jcaa/article/view/2214

Issue

Vol. 38 No. 1 (2010)

Section

Technical Articles

License

Author Licensing Addendum

This Licensing Addendum ("Addendum") is entered into between the undersigned Author(s) and Canadian Acoustics journal published by the Canadian Acoustical Association (hereinafter referred to as the "Publisher"). The Author(s) and the Publisher agree as follows:

  1. Retained Rights: The Author(s) retain(s) the following rights:

    • The right to reproduce, distribute, and publicly display the Work on the Author's personal website or the website of the Author's institution.
    • The right to use the Work in the Author's teaching activities and presentations.
    • The right to include the Work in a compilation for the Author's personal use, not for sale.

  2. Grant of License: The Author(s) grant(s) to the Publisher a worldwide exclusive license to publish, reproduce, distribute, and display the Work in Canadian Acoustics and any other formats and media deemed appropriate by the Publisher.

  3. Attribution: The Publisher agrees to include proper attribution to the Author(s) in all publications and reproductions of the Work.

  4. No Conflict: This Addendum is intended to be in harmony with, and not in conflict with, the terms and conditions of the original agreement entered into between the Author(s) and the Publisher.

  5. Copyright Clause: Copyright on articles is held by the Author(s). The corresponding Author has the right to grant on behalf of all Authors and does grant on behalf of all Authors, a worldwide exclusive license to the Publisher and its licensees in perpetuity, in all forms, formats, and media (whether known now or created in the future), including but not limited to the rights to publish, reproduce, distribute, display, store, translate, create adaptations, reprints, include within collections, and create summaries, extracts, and/or abstracts of the Contribution.