Casella CEL CEL-393 - Manual (Page 66)

sources that could cause hearing loss to operators working in the
immediate area.
Proceed as follows.
1. Switch the instrument on, and check the battery level.
For correct operation with alkaline manganese batteries, the
voltage should be greater than 8V. Replace the batteries if the
indication is below this level.
2. Calibrate the sound level meter with a CEL-284/2 Calibrator
Type 1 to obtain a reading of 114.0dB as described in Section
8.2.
3. Move the F-P-I-S switch to F for fast time weighting.
4. Ensure that the Off-F1:1-F1:3 switch is Off.
5. Move the Lin-A-POWER OFF switch to A for A-weighted
measurements.
When the instrument is switched on, it defaults to measurement
in the 70-130dB(A) range.
6. If very large impulses are anticipated, press 8R (8 immediately
followed by R) to select the measurement range between 80
and 140dB(A).
7. Press 0835C (if the actual time is 8.35 am for example) to set
the correct time into the instrument's real time clock.
8. Press 1C to set a 1 minute calculation and period storage.
9. Press 09000C to delay the start of measurements to 9.00 am
(on the same day).
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