New IEEE Standard – Inactive – Withdrawn. Approved methods for conducting tests and reporting results to effect the uniform determination of rotating-electric-machine sound under steady- state conditions with an accuracy of 3 dB are defined. Three acoustical environments are considered: free field, reverberant field, and semireverberant field. Installation and operation of the machine is discussed. The test procedure assumes the presence of pure tones or the predominance of discrete frequencies in the sound spectrum.<\/p>\n
| PDF Pages<\/th>\n | PDF Title<\/th>\n<\/tr>\n | ||||||
|---|---|---|---|---|---|---|---|
| 6<\/td>\n | 5.3 Semireverberant Field 5.4 Test to Determine Type of Environment 5.5 Background Level 6.1 Standard 6.2 Additional 7 Methods of Measurement Free Field Over a Reflecting Plane Location of Measurement Points <\/td>\n<\/tr>\n | ||||||
| 10<\/td>\n | 1 Scope 2 Definitions and Terms Sound Pressure Level A-Weighted Sound Level Octave Band Level Sound Power Level Table 1 Preferred Frequencies for Acoustical Measurements <\/td>\n<\/tr>\n | ||||||
| 11<\/td>\n | A-Weighted Sound Power Level Prescribed Surface Equivalent Radius Reference Distance Reference Radius 2.10 Background Level 2.11 Mean Sound Pressure Level or Mean Sound Level 2.12 Machine 2.12.1 Small Machine 2.12.2 Medium Machine Large Machine Corrections to Be Applied to Obtain A – Weighting <\/td>\n<\/tr>\n | ||||||
| 12<\/td>\n | Installation and Operation 3.1 Machine Mounting 3.1.1 Field Installation 3.1.2 Test Mounting Multiunit Machines Operating Condition No-Load Test Full-Load Test 4 Measuring Instruments 4.1 Sound Level Meter 4.2 Band Filter Networks 4.3 Level Recorder 4.4 Sound Measuring Systems 4.4.1 Microphone 4.4.2 Interconnecting Cable <\/td>\n<\/tr>\n | ||||||
| 13<\/td>\n | 4.4.3 Microphone Signal Amplifier 4.4.4 Frequency Analyzer 4.5 Calibration 4.6 System Check Out 4.7 Electrical Characteristic Measurement Instrumentation 5 Test Environment 5.1 Free Field Over a Reflecting Plane 5.1.1 Free-Field Conditions in a Test Room 5.1.2 Other Free-Field Situations 5.2 Reverberant Field <\/td>\n<\/tr>\n | ||||||
| 15<\/td>\n | 7.1.1.1 Small Machines 7.1.1.2 Medium Machines 7.1.1.3 Large Machines 7.1.2 Test Procedure Fig 1 (A) Prescribed Points Small Machines Fig 1 (B) Six-Point Hemisphere Small Machines <\/td>\n<\/tr>\n | ||||||
| 16<\/td>\n | 7.1.3 Measurement Corrections Calculation of the Mean Level Using Octave Band Mean Sound Pressure Levels Free Field Over a Reflecting Plane Prescribed Points Medium Machines Fig 2 (B) Twelve-Point Hemisphere Medium Machines <\/td>\n<\/tr>\n | ||||||
| 17<\/td>\n | Calculation of the A -Weighted Sound Power Level Over a Reflecting Plane Prescribed Points Large Horizontal Machines <\/td>\n<\/tr>\n | ||||||
| 18<\/td>\n | 7.2 Reverberant Field Reference Sound Source Location of Measurement Points 7.2.3 Test Procedure 7.2.4 Measurement Corrections Calculation of Mean Level Octave Bands Prescribed Points Large Vertical Machines <\/td>\n<\/tr>\n | ||||||
| 19<\/td>\n | a Free Field Over a Reflecting Plane Over a Reflecting Plane 7.2.9 Calculation of A-Weighted Sound Power Level Semireverberant Field Reference Sound Source Location of Measurement Points 7.3.3 Test Procedure 7i3.4 Measurement Corrections Calculation of the Mean Level Calculation o \u2022 the Sound Power Level in Octave Bands <\/td>\n<\/tr>\n | ||||||
| 20<\/td>\n | Field Over a Reflecting Plane Over a Reflecting Plane 7.3.9 Calculation of A-Weighted Sound Power Level 8 Test Report <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":" IEEE Test Procedure for Airborne Sound Measurements on Rotating Electric Machinery<\/b><\/p>\n |