407768 Version 2.0 06/06
3
Sound Level Meter Operation
Meter Power
1. The meter is powered by a 9V battery. The battery compartment is located on the rear
of the meter and the compartment cover is secured by one Phillips screw. When the
battery icon appears on the top left corner of the meter's display, replace the battery.
2. Press the POWER button to turn the meter on. Note that the Meter is equipped with an
Auto Power Off feature that shuts the meter off after 10 minutes. To defeat Auto Power
Off, put the meter in Record mode by pressing the REC MAX/MIN button.
3. Press the POWER button to turn the meter off.
Default Configuration
1. The meter's default configuration is as follows: Auto Range, 'A' Frequency Weighting,
and 'FAST' Response Time
2. The lower portion of the LCD will reflect the meter's configuration, i.e., 'A', 'Fast', 'Auto'.
Measurement Considerations
1. Use a windscreen (not included) to cover the microphone in windy conditions.
2. Calibrate the meter often, especially if the meter has been idle for a long period of time.
3. Do not store/operate the meter in areas of high temperature or humidity.
4. Keep the meter and the microphone dry.
5. Avoid severe vibration when using the meter.
6. Remove the battery when the meter will be stored for long periods of time.
Frequency Weighting
Change the Frequency Weighting by pressing the 'A/C' button. The 'A' or 'C' icon will
display on the lower left-hand area of the LCD.
Note:
With ‘A’ weighting selected, the meter responds like the human ear (boosting and
cutting the noise amplitude over the frequency spectrum - see Appendix). ‘A’ weighting is
used for environmental measurements, OSHA regulatory testing, law enforcement, and
workplace design. Select ‘C’ weighting for flat response measurements (no boost or cut).
‘C’ weighting is suitable for the sound level analysis of machines, engines, etc. Most OSHA
related testing is performed using 'A' Weighting and SLOW Response Time settings.
Response Time
Change the Response Time by pressing the 'FAST/SLOW' button. The 'FAST' or 'SLOW'
icon will display on the lower left-hand area of the LCD.
Note:
Select FAST to capture noise peaks and noises that occur very quickly. In FAST
mode, the meter responds in 200ms. Select the SLOW Mode (meter responds in 500ms)
to monitor a sound source that has a reasonably consistent noise level or to average
quickly changing levels. Selection of Fast or Slow is determined by the application and any
directives or standards related to that application.
Auto/Manual Range
Press the RANGE button to scroll through the following ranges: Auto, 30-80dB, 50-100dB,
and 80-130dB. The display will reflect the range for each button press.
Calibration
The Sound Level meter should be calibrated before each use; an external sound level
meter calibrator is required. Set the meter to the Manual range (50-100dB), FAST
response and ‘A’ weighting before starting.
1. Place the external calibrator over the Sound Level Meter's microphone and turn the
Calibrator on.
