Casella CEL CEL24X - Manual (Page 11)

C. MEASUREMENT RANGE (30 – 100dB or 60 – 130dB)
Care should be taken to select the correct measurement range depending
on the noise climate being measured. Make sure the noise being measured is
within the range selected. If the Over Range indicator (
) is displayed the
incorrect range has been selected. (Refer to Figure 7 [C]). If the noise level is
lower than the selected measurement range ‘--.-dB’ will be displayed.
D. TIME WEIGHTINGS
FAST - Use this setting for comparatively stable noise.
SLOW - Use this setting for noise with a slow variation.
IMP (Impulse) - Use this setting for noise with rapid variation and impulsive
noise.
Note: If unsure please refer to your local legislation and application
standards.
E. FREQUENCY WEIGHTINGS
Frequency weightings are used to represent the human ears response to
noise.
A WEIGHTING - Make this selection for general noise measurements.
C WEIGHTING - Make this selection for very high noise levels.
Note: If unsure please refer to your local legislation and application
standards.
F. AVERAGE SETTING (CEL-244/246 ONLY)
The parameter to measure average noise can be set to Leq or Lavg. This is
dependent on local legislation which sets the exchange rate (Q) to either 3
or 5 respectively. The Q value determines the increase in dB associated
with the doubling of risk to hearing damage. Q=3 means that the increase in
hearing damage risk doubles every 3dB increase in noise, respectively Q=5
means that risk to hearing damage doubles every 5dB increase in noise
level. Use Leq (Q=3) for EU based workplace noise regulations and Lavg
(Q=5) for US/OSHA based noise legislation.
Note:
If unsure please refer to your local legislation and application
standards.
G. LOGGING INTERVAL SCREEN (CEL-246 ONLY)
In Figure 8 (C), the currently selected logging interval is displayed and is
also shown above the Right key (B). Press the Right key (B) to change the
logging interval. Press Left key (A) to exit the settings menu and return to
the measurement screen.
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