The use of noise meters and what factors affect noise meter measurements
Factors affecting the choice of noise meter
Noise meter is mainly used to measure noise, and the classification of noise measurement is mainly as follows:
1. From the measurement object, it can be divided into the measurement of the characteristics of environmental noise ( sound field ) and the measurement of the characteristics of the sound source.
2. From the time characteristics of the sound source or sound field, it can be divided into steady state noise measurement and non-steady state noise measurement. Non-stationary noise can be divided into periodic variation noise, irregular variation noise and impulse 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 precision of measurement requirements, it can be divided into precision measurement, engineering measurement and noise census.
The general use of noise meter
Whether the noise meter is used correctly or not, it directly affects the accuracy of the measurement results. Therefore, it is necessary to introduce the use of noise meter.
1,Precautions
a. Read the instruction manual before use to understand how to use the instrument and precautions.
b. Pay attention to the polarity of the battery or external power supply and do not connect it in reverse. Long-term use should be removed from the battery, so as not to leak liquid damage to the instrument.
c. Do not disassemble the microphone to prevent it from being thrown or dropped, and place it properly when not in use.
d. Avoid placing the instrument in places with high temperature, humidity, sewage, dust and air or chemical gases with high hydrochloric acid and alkali content.
e. Do not disassemble the instrument without permission. If the instrument is not normal, can be sent to the repair unit or factory overhaul.
2, sensitivity calibration, in order to ensure the accuracy of the measurement, before and after use to be calibrated. Match the sound level calibrator with the microphone, turn on the calibration power, read the value, adjust the sensitivity potentiometer of the noise meter to complete the calibration.
3,Measuring method, when measuring, the instrument should choose the right gear according to the situation, hold both sides of the noise meter with two hands flatly, and point the microphone to the sound source to be measured, or use the extension cable and extension pole to reduce the influence of the noise meter's appearance and the human body on the measurement. The position of the microphone should be determined according to the relevant regulations.
