How to Maintain a Noise Meter Properly
A noise meter is a fundamental instrument in noise measurement. A noise meter generally consists of a condenser microphone, preamplifier, attenuator, amplifier, frequency meter network, and effective value indicator head. Usage of noise meter: Use of noise meter
A noise meter is a fundamental instrument in noise measurement. A noise meter generally consists of a condenser microphone, preamplifier, attenuator, amplifier, frequency meter network, and effective value indicator head.
Instructions for using a noise meter:
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, and hold the noise level with both hands.
The sound level meter used for measuring noise can be divided into four types of response based on sensitivity:
1. Hurry up. 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.
2. Slow down. 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.
3. Pulse or pulse hold. The rise time of the gauge needle is 35ms, used to measure pulse noise with longer duration, such as punch presses, hammers, etc. The measured value is the maximum effective value.
4. Peak retention. The rise time of the meter needle is less than 20ms. It is used to measure pulse sounds with a short duration, and the measured value is the peak value, which is the maximum 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.
The working principle of a noise meter is:
The sound is converted into an electrical signal by a microphone, and then the impedance is transformed by a preamplifier to match the microphone with an attenuator. The amplifier adds the output signal to the network, performs frequency weighting on the signal (or an external filter), and then amplifies the signal to a certain amplitude through attenuators and amplifiers before sending it to the effective value detector.
Noise meters are mainly used to measure environmental noise, conduct noise engineering, quality control, and health prevention and control. Used for measuring noise volume in various occasions such as factories, offices, transportation roads, audio systems, homes, as well as air conditioning, refrigerators, etc.
