Carrying Out A Measurement - VOLTCRAFT 105031 Operating Instructions Manual

Time rating fAST/SLOW
The signal can be measured with two different measuring intervals. For rapidly changing sound
levels (horn, shot, etc.), you have to set the time rating to "FAST". The measuring duration is
125 ms/measuring operation. For slow and persistent sound levels (noise, humming, etc.), the time
rating must be set to "SLOW". The measuring duration is 1 s/measuring operation.
To switch, press the button "FAST/SLOW".

11. CARRyING OUT A MEASUREMENT

Wear sufficient hearing protection when measuring loud sound sources. There is
risk of hearing damage!
Observe the permissible ambient temperatures (Technical data) in order to avoid
incorrect measurements.
Calibration
The sound level meter corresponds to the European standard EN 61 672-1 for sound level meters.
To apply the device in line with the standard, it must be calibrated with the benchmark curve A (dBA)
prior to each measuring operation, meaning tested and if necessary matched with a sound calibrator
Class 2 acc. to IEC 60942. The accuracy must be checked again after each measuring operation.
Proceed as follows for calibration:
Switch the sound level meter on.
Select the corresponding settings (dBA, measuring range up to 100 dB or higher and FAST time
rating).
If necessary, deactivate the the functions "MAX" and "HOLD".
Plug the microphone of the sound level meter into the opening of the sound calibrator. Ensure a tight
fit so that the calibration chamber in the sound calibrator is sealed.
Set the following parameters on the sound calibrator: 94 dB at 1 kHz
The measuring device should now show a sound level of 94 dBA. If this is not the case, the measu-
ring device must be calibrated.
With the enclosed screwdriver, carefully turn the calibration point on the side (CAL calibration
potentiometer 17) until the value on the display is exactly 94.0 dBA.
The measuring device is ready for use.
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