How to determine whether a sound level meter's measurement is correct
The sound level meter is the basic instrument for measuring noise, and now the 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 of the sound level meter every year. After passing the verification, a verification certificate will be issued, and it can be used normally only after a qualified conclusion is drawn.
The calibration certificate of the sound level meter is useless, and it can only be used normally if a verification certificate is issued and a qualified conclusion and accuracy level are drawn. The daily verification of sound level meters requires a lot of equipment, such as calibrators, standard condenser microphones, signal generators, measuring amplifiers, tone burst signal generators, precision attenuators, voltmeters, sound sources, anechoic boxes (free field), etc., all of which are fully equipped and require at least 30W or more, and occupy a large space, and have certain technical requirements. The verification device cannot issue a sound level meter verification certificate.
There are some precautions when using the sound level meter. When using the sound level meter, pay attention not to connect the two poles of the battery reversely. When the sound level meter is not used for a long time, the battery should be removed to avoid battery leakage and corrosion of the sound level meter. Pay attention to replace the battery in time when the voltage of the sound level meter is insufficient.
The sound level meter is powered by batteries. You should check whether the battery voltage meets the requirements. The switch of the ammeter is set to the "battery position", and the "attenuator" can be set arbitrarily. At this time, the indication on the ammeter should be within the rated battery voltage range, otherwise the battery needs to be replaced. 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, and remember not to reverse the battery.
