Analysis of daily failure factors of noise meters
The correct use of a noise meter directly affects the accuracy of measurement results. When measuring, the instrument should select the correct gear according to the situation. Hold the sound level meter used for noise measurement with both hands, and the response of the meter head can be divided into four types according to sensitivity:
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 the effective value.
2. "Quick"
The time constant of the meter head is 125ms, which is generally used to measure unstable noise and transportation noise with large fluctuations. Fast gear approaches the human ear's response to sound.
3. "Pulse or pulse hold"
The rise time of the gauge needle is 35ms, used to measure pulse noise with a longer duration, such as punch presses, hammers, etc. The measured value is the maximum effective value.
4. "Peak Maintenance"
The rise time of the meter needle is less than 20ms. It is used to measure pulse sounds with short duration, such as gun, cannon, and explosion sounds. The measured value is the peak value, that is, the large value. Distance measuring instrument, height measuring instrument, laser projection instrument, flow meter, GPS thickness measuring instrument, level instrument, flat panel instrument, waveform recorder, testing fixture, voltage and current recorder, data collector, graphic recorder, flow integrator instrument.
To ensure the accuracy of the noise meter measurement, a sound level calibrator should be used for calibration before and after using the noise meter. Connect the sound level calibrator to the microphone, turn on the calibration power, read the value, adjust the sensitivity potentiometer of the sound level meter, and complete the calibration.
