How to judge whether the sound level meter measurement results are accurate
Sound level meter is a basic instrument for measuring noise. Now sound level meter has been widely used in our social life. It can be used in environmental protection, labor hygiene, industrial enterprises, scientific research and teaching and other fields to complete environmental noise measurement, sound power level measurement, equipment noise measurement and architectural acoustics measurement, etc.
During the use of the sound level meter, it must be sent to the Metrology Institute for verification every year. If the sound level meter passes the verification, a verification certificate will be issued, and a qualified conclusion can be drawn before it can be used normally.
The calibration certificate of the sound level meter is useless. Only if a calibration certificate is issued and a qualified conclusion and accuracy level are obtained, it can be used normally. The daily calibration of sound level meters requires a lot of equipment, including calibrators, standard condenser microphones, signal generators, measurement amplifiers, burst signal generators, precision attenuators, voltmeters, sound sources, mufflers (free field), etc. It requires at least 30W to be fully equipped, and it occupies a large space and has certain technical requirements; at the same time, there are not many instruments for sound level meter verification, and the standard equipment must be submitted for inspection every year, so establishing a complete set of acoustic verification equipment is not cost-effective, resulting in Many provincial metrology institutes have not established sound level meter calibration equipment and cannot issue sound level meter calibration certificates.
There are some precautions when using the sound level meter. When using the sound level meter, be careful not to connect the battery poles reversely. When the sound level meter is not used for a long time, remove the battery to avoid battery leakage and corrosion of the sound level meter. Also pay attention to replace the battery in time when the voltage of the sound level meter is insufficient during use.
The sound level meter is powered by a battery. You should check whether the battery voltage meets the requirements. Place the meter switch to the "battery position" and the "attenuator" can be set arbitrarily. At this time, the indication on the meter should be within the rated battery voltage range, otherwise you need to perform Replace the battery. Pay attention to the polarity when installing the battery or external power supply. Pay attention to the polarity when installing the battery or external power supply. Remember not to connect the battery reversely.
