1 Subject content and applicable scope
This standard defines a measurement method for rotating electrical machinery operating under a standard deviation which is greater than 4 dB (for the electrical machinery with broadband spectral characteristic), or 5 dB (the electrical machinery with discrete frequency constituent), and the result can be expressed in A-weighted sound power level.
Where the test conditions cannot meet the requirements of GB 10096.1 and the accuracy of the test method can be reduced (for instance, an electrical machinery in the field or the electrical machinery which cannot be operated by a single machine butneeds to measure the noise), the method specified in this standard should be applied.
2 Normative references
GB 3785 Electric, sonic properties and measuring methods for sound level meters
JJG 188 Verification regulation of sound level meters (trail)
JJG 176 Verification regulation of sound pressure level calibrators
GB 3768 Determination of sound power levels of noise sources -- Simple method
3 Test items
a. Determination of the A-weighted mean sound pressure level
b. Determination of the A-weighted sound power level Lw
4 Measuring instrument
4.1 Requirements for measuring instrument
The instrument shall adopt the sound level meter that meets the requirements of GB 3785 and with an accuracy of not lower than II type, or other acoustical instrument with equal accuracy.
Foreword i
1 Subject content and applicable scope
2 Normative references
3 Test items
4 Measuring instrument
5 Installation requirements for electrical machinery
6 State of electrical machinery during test
7 Correction for background noise
8 Distribution of measuring positions
9 Calculation of mean sound pressure levels and sound power levels of the electrical machinery
10 Test records and information to be reported
