IEEE 2400-2016 pdf free
IEEE 2400-2016 pdf free.IEEE Standard for Wind Turbine Aero Acoustic Noise Measurement Techniques.
The complete acoustic measurement system includes the recordings, a data record, analysis, and repeated calibration before and after measurement. The calibration instrument should satisfy the Class 1 instrument requirement in IEC 60942:2003. Sound-level meters and acoustic calibrators should have current laboratory calibration certificates traceable to the National Institute of Standards and Technology (NIST). It is worth noting that Type 1 instrumentation’s ANSI filter characteristics have a long impulse response time at low frequencies.
At 1 Hz, the ANSI 1/3 octave band impulse response is close to 5 s! Thus, unfortunately, ANSI flters do not capture the fast peak pressure changes occurring in low and infrasonic frequencies. The rms levels reported in this study are understating the true range and modulation of the levels obtained compared to the time response of the human ear. The octave-band and fat-Fourier-transform (FFT) results in this stuady should be considered suggestive of the possible range of pressure changes and detectability for the human ear, thereby prompting the need for more extensive field and laboratory research. The calibration frequency is the same as specified in IEC 61400-11.
4.1.4 Microphone with ground board and windscreen shield Sensors require a corresponding bottom and protective windscreen cover to reduce interference from the surrounding environment and rflctive wave interference.
4.1.5 Automatic recorder
In worksite testing procedures, the automatic recorder and the sound level spectrometer are used in combination for continuous measurement, sound level and frequency spectrum recording, and recording noise changesover time.
4.1.6 Sound recorder
In noise measurement, the complete noise conditions cannot be tested by the sound-level meter or frequency spectrometer. For obtaining all the noise conditions, the sound recorder needs to record the acoustic signal for subsequent data analysis.
4.2 Non-acoustic instruments
4.2.1 Anemometer
The maximum deviation of an anemometer and its signal-processing equipment should be +0.2 m/s within the scope of the wind speed 4 m/s through 14 m/s. The anemometer needs to be able to measure the average wind speed of the synchronization time interval of noise measurement.
4.2.2 Electricity sensor
Elctricity sensors include voltage and current sensors. The sensors should satisfy the Class 1 instrument requirements in IEC 60688:2012.IEEE 2400 pdf free download.
