CESVA SC310, Руководство пользователя

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8. APPENDIX C: Extended frequency module
The extended frequency module of the SC310 sound level meter adds 2 modes of
measurement: Extended Frequency Module for 1/3 Octave Band Analysis and FFT (Fast
Fourier Transform) Narrow Band Frequency Analysis Mode.
The Extended Frequency Mode for 1/3 Octave Band Analysis of the SC310 sound level
meter analyses in real time the spectrum in 1/3 octave bands from 10 Hz to 20 kHz in all
dynamic measurement range (no scale settings). The SC310 measures the equivalent
continuous sound pressure level with a programmable integrating time from 1 second to 99
hours without frequency weighting and the overall equivalent continuous sound pressure
level for the consecutive integrating time T with the frequency weighting A, C and Z.
Simultaneously, the SC310 measures, in real time, “short” levels (125 ms integration time)
for the corresponding bands and overall values. Also, the SC310 measures a special
acoustical functions with the purpose to provide complementary information to the graphical
and numerical screen of the spectrum analyser in 1/3 octave bands.
The major applications of this mode include: the frecuencial analysis of noise produced by
machinery especially at low frequency, the evaluation of tonal components and impulsivity,
the detection and identification of noise sources, etc.
The FFT Narrow Band Frequency Analysis Mode of the SC310 sound level meter carries out
a frequency analysis with constant bandwidth filters covering the frequency range from 0 Hz
to 20 kHz in real time and in all dynamic measurement range (no scale settings). The FFT
analysis has 430 effective lines with a resolution of 47 Hz. The SC310 measures the
equivalent continuous sound pressure level with a programmable integrating time from 1
second to 99 hours without frequency weighting for each FFT line.
Unlike an spectrum obtained from a porcentual band analysis the FFT frequency analysis
obtains the spectrum with frequency bands of constant width, the major applications of this
mode include: frequency analysis from continuos and transient signals (environmental and
industrial), detection and evaluation of tonal components when these are between
neighbouring one third octave bands, etc.
The Extended Frequencial Module for 1/3 octave band analysis of the SC310 it is not
included with the SC310. Is an optional module and it can be acquired when buying the
SC310 or later. To incorporate it, you just have to contact your official
distributor and supply him the serial number of your sound level meter and manage the
transaction. In a few days you will receive a CD with the activation program.
8.1 Activation of the Extended frequency analysis module
To activate the Extended frequency module (EF):
•
Insert in the CD-ROM drive the CD that you have received. The activation program ‘SC310
EF module Activator’ will be automatically executed. If not, you should execute the
SETUP.EXE program in the CD-ROM drive.
• Follow the steps.