Noise Meter - Classification and Usage
Noise Meter - Classification
1. From the measurement object, it can be divided into the characteristic measurement of environmental noise (sound field) and the measurement of sound source characteristics.
2. From the time characteristics of the sound source or sound field, it can be divided into steady-state noise measurement and unsteady-state noise measurement. Non-stationary noise can be divided into periodic noise, irregular noise and pulse sound.
3. From the frequency characteristics of the sound source or sound field, it can be divided into broadband noise, narrowband noise and noise containing prominent pure tone components.
4. From the accuracy of measurement requirements, it can be divided into precision measurement, engineering measurement and noise survey.
Noise Meter - How to Use
Whether the noise meter is used correctly or not will directly affect the accuracy of the measurement results. When measuring, the instrument should select the correct gear according to the situation, and hold the noise with both hands
The sound level meter used to measure noise can be divided into four types according to the sensitivity of the meter head response:
1. "Slow". The time constant of the meter head is 1000ms, which is generally used to measure steady-state noise, and the measured value is an effective value.
2. "Fast". The time constant of the meter head is 125ms, which is generally used to measure unstable noise and traffic noise with large fluctuations. The fast gear is close to the human ear's response to sound.
3. "Pulse or pulse hold". The rising time of the watch needle is 35ms, which is used to measure the pulse noise with a long duration, such as punch press, hammer, etc. The measured value is the maximum effective value.
4. "Peak hold". The rise time of the hands is less than 20ms. It is used to measure short-duration impulsive sounds, such as guns, cannons and explosions, and the measured value is the peak value. That is the maximum value. Range finder, altimeter, laser liner, flowmeter, GPS thickness gauge, leveler, flat panel, waveform recorder, test fixture, voltage and current recorder, data recorder, graphic recorder, and flow totalizer.
