2measurement of sound pressure level - spl – Casella CEL CEL-414 User Manual
Page 26
6. Fit the windshield when one is to be
used.
7. Configure the instrument to measure
any required parameter by sliding
the P-I-F-S, A-L-FA-FL/A-C-FA-FL,
and 80-50-20 switches to the
settings required for the selected
parameter.
Changing the settings of any of these
switches performs a general reset
of the complete instrument, and
resets the measuring period for ALL
PARAMETERS to zero.
WHEN SEVERAL PARAMETERS
ARE TO BE CALCULATED AT THE
SAME TIME, USE THE RESET
FACILITY WITH GREAT CAUTION.
Some combinations of function and
time weighting must not be used,
and cannot be selected. Full details
are given in Table 1 and in a table on
the back of the instrument.
8. If necessary, press the RESET button
while a parameter is being displayed
to reset ONLY the measurment
parameter for that particular period.
6.2Measurement of Sound
Pressure Level - SPL
1. Sound Pressure Level measurement
is selected automatically at the end
of the self test, otherwise use the
FUNCTION buttons to step the
arrow marker round the display (as
described in Sections 3.2 and 3.4).
Note:
SPL cannot be selected if peak P) is
the chosen time weighting.
Figure 8 shows the settings for Linear
measurement, move the A-L-FA-FL/
A-C-FA-FL switch to L, A or
C to use the internal weighting
networks, (or to FA or FL for
frequency analysis).
The instantaneous sound pressure
level is shown on the digital portion
of the display with a resolution of
0.1 dB. This display is updated every
500 ms, irrespective of the time
weighting in use.
The instantaneous sound pressure
level is also shown on the analog
display with a resolution of 1 dB
updated every 125 ms.
6.3Measurement of One
Second Mode - 1SM (not
CEL-266/3, CEL-328/3 or
CEL-414/3)
Measurement of the one second maxi-
mum profile is possible only when the
880020
Pause
Reset
CAL
Function
Range
OFF
BAT
ON
80
50
20
P
I
F
S
A
L
FA
FL
DATUM
SEL
EVENT
1SM
L
40+
10
15
20
25
5
LEQ
SPL
MAX
DUR
BAT
PSE
LT3
LT5
Figure 8: Settings for SPL
measurement
Page 22 - General CEL Sound Level Meters Handbook