What are the common faults of noise meters
It is well known that the vibration will produce noise, such as: rotating machinery, impact, resonance, friction, etc., and the flow of noise generated by the place, environmental noise, noise generated by combustion, other noise. The generation of noise brings us the influence of life and work. To know the size of the noise will have to use the noise measuring instrument.
1, the monitor does not show
(1)The internal battery connection line is disconnected or the battery contact is not good: weld the connection line and replace the battery contact piece. (2) Battery damage: replace the battery.
2, the measurement reading is obviously low or calibrated when the school is not 94.0dB.
(1) microphone sensitivity is too low or damaged: replace the microphone and recalibrate.
(2) Preamplifier contact with the microphone contact is not good: cleaning contact.
(3) The plug of preamplifier is not in good contact with the socket of the host: replace the plug and socket.
(3) The reading is high when measuring low sound level , and the ground wire of preamplifier has bad contact: tighten the outer sleeve.
The correct use of noise meter
Whether the noise meter is used correctly or not, it directly affects the accuracy of the measurement results. Measurement, the instrument should be selected according to the situation of the correct gear, two hands flat grip noise measurement noise with a sound level meter, the meter head response according to the sensitivity can be divided into four kinds:
1、"Slow"：The time constant of the meter head is 1000ms, which is generally used to measure the steady state noise, and the measured value is the RMS value.
2、"Fast"：The time constant of the meter head is 125ms, which is generally used for the measurement of large fluctuation of unsteady noise and transportation noise. Fast gear is close to the human ear's response to sound.
3、"Pulse or pulse hold": the meter needle rise time is 35ms, used to measure the pulse noise with longer duration, such as punch, press hammer, etc. The measured value is the maximum RMS value.
4、"Peak hold"：The rise time of the meter needle is less than 20ms. It is used to measure the impulse sound with short duration, such as the sound of cannon and explosion, and the measured value is the peak value. That is, the maximum value. Rangefinder altimeter laser projector flow meter GPS thickness gauge level meter plate meter waveform recorder test fixture voltage and current recorder data set recorder graphic recorder flow accumulation meter.
