Sound level meter calibration problems that need to be resolved
Sound level meter is the most basic noise measuring instrument. It is an electronic instrument, but it is different from objective mechanical electronics such as ammeter. When converting an acoustic signal into an electronic signal, it can simulate the time characteristics of the human ear's response rate to the frequency of the sound wave; there are characteristics of different sensitivities and strength characteristics of changing characteristics at different tones. A sound level meter is a subjective electronic instrument.
Whether the sound level meter is used properly or not will directly affect the accuracy of the measurement results. Therefore, it is necessary to introduce the application of the sound level meter.
1. Selection of sound level meter application environment: select a representative detection location, away from the road and away from the wall, so as to reduce the additional damage of the reflective surface of the road and wall.
2. The temperature standard stipulates that when there is no rain or snow, the sound level meter should keep the pulse damper of the microphone clean. When the wind speed is above level 3, a wind cover must be added (to prevent the influence of wind noise), and the measurement should be stopped if the wind speed is above level 5.
3. Turn on the sound level meter, remove the sound level meter, and put on the sensor.
4. Place the sound level meter to measure the situation, check the rechargeable battery, and then calibrate the sound level meter.
5. Checklist (refer to the common natural environment sound pressure level size), adjust the measurement range of measurement.
6. Next, you can use various functions such as fast (measure the instantaneous value of the environment where the sound pressure level changes greatly), slow (measure the average value in the environment where the sound pressure level does not change greatly), monopulse (measure the single pulse sound source), and filter (measure the sound pressure level of a specific frequency band).
7. According to the recorded data, it can also be connected to a printer or other computer server for automatic collection. Comb instruments and place in specific areas.
What must be paid attention to when calibrating the instrument:
1) Read the instructions of the article before application to master the operation method and common problems of the instrument.
2) The instrument should be prevented from being placed in areas with high temperature, humidity, waste water, dust, and gas containing sulfuric acid and alkali, or organic chemical vapor.
3) Pay attention to the optical rotation when installing rechargeable batteries or external power supply, and avoid reverse connection. The rechargeable battery should be selected for long-term use, so as not to damage the instrument due to liquid leakage.
4) Do not disassemble the microphone, avoid throwing it, and place it safely when not in use.
5) Do not disassemble or assemble the instrument without authorization. If the instrument is abnormal, it should be sent to the maintenance company or factory for maintenance.
6) During the whole application process, if an undervoltage protection alarm appears on the LCD screen, the battery should be replaced immediately.
7) Before the sound level meter is measured, it can be heated for 2 minutes, and it can be heated for 5 to 10 minutes in wet and cold weather.
Sensitivity Calibration
To ensure accurate measurements, calibration should be performed before and after use.
Fit the sound pressure level calibrator on the microphone, turn on the calibration power supply, load the calibration value, adjust the sensitivity resistor of the noise meter, and perform calibration.
