How to Calibrate a Sound Level Meter?

Sound level meter is a basic noise measuring instrument, which is a subjective electronic instrument, different from objective electronic instruments such as voltmeter. It can convert sound signals into electrical signals, and can simulate the time characteristics of the human ear's response speed to sound waves, the frequency characteristics with different sensitivities to high and low frequencies, and the intensity characteristics of changing frequency characteristics at different loudness.

Why do you need to calibrate the sound level meter before using it?

The sound level meter measurement is to convert the vibration wave signal of the metal diaphragm of the microphone (microphone head) at the front of the sound level meter into an electrical signal through the vibration wave caused by the sound signal (sound wave), and then pass through the special weighting network and circuit. After the operational amplification, the noise decibel value is displayed by digital or meter.

The quality of the air is unstable. For example, the temperature, humidity, atmospheric pressure, etc. of the air will change at any time due to the influence of the environment and other factors. In this way, it is necessary to ensure the accuracy of the air vibration wave signal received by the metal diaphragm of the microphone. Adjust the sensitivity of the microphone accordingly.

The process of adjusting the sensitivity of the microphone is to calibrate the sound level meter.

Calibration and verification method of sound level meter

1. After the sound level meter is turned on, there will be four options: measure, set, recall, and calibrate. After Z - an option is the calibration option, just move the cursor to this option.
2. After entering the calibration page, there will still be four options: view, calibrate, apply, and modify. Place the cursor on the second option, calibration option, and then select the calibration option.
3. Insert the sensor of the sound level meter into the upgrade calibrator, and then turn on the switch of the calibrator, the calibrator will emit a standard sound level, - when it is ready, press the calibration start, and the instrument can be automatically calibrated.
4. When the data displayed by the sound level meter reaches 93.8dB(A), the instrument is calibrated.

Sound Level Meter Calibration Considerations

1. Before calibrating, read the instructions of the article 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, wet and cold, waste water, dust, gas containing sulfuric acid, high alkali content or organic chemical vapor.
3. Install the rechargeable battery or external power supply, pay attention to the optical rotation, and do not connect it in reverse. Long-term rechargeable batteries should not be selected to prevent liquid leakage from damaging the instrument.
4. Do not disassemble and assemble the microphone to avoid throwing and falling, and place it securely when not needed.
5. Do not disassemble the instrument without permission. If the instrument is abnormal, it should be sent to the maintenance company or factory for maintenance.
6. During the whole process of application, an undervoltage protection alarm appears on the LCD screen, and the battery should be replaced immediately.
7. Before the sound level meter measurement, start the heating for 2 minutes, and heat it for 5 to 10 minutes in wet and cold weather.