Svantek SV 971A, Руководство пользователя

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SV 971A User Manual
69
10 1/1- AND 1/3-OCTAVE ANALYSER
The real-time 1/1-octave or 1/3-octave analysis is performed in parallel with the SLM or SEM
measurements. All digital pass-band filters (eleven 1/1-octave with centre frequencies from 16 kHz down
to 16.0 Hz and thirty five 1/3-octave with central frequencies from 20 kHz down to 8 Hz; in the
“base
ten
” system) are working in real-time with the weighting filters (
Z , A , B or C ) and the LEQ detector
( Linear , Fast or Slow ). This enables a spectrum pre-weighting with one of the selected broadband
frequency curves if required for the application such as the provision of hearing protectors during the
control of high workplace noise.
For each octave or one-third octave band, the Leq, Peak,
Min or Max result is calculated and presented as a bar on
the spectrum graph. Spectra can be examined on a
display in the
Spectrum view.
The read-out of the spectrum values can be done using
a vertical cursor.
Besides results for bands three Total values are measured and displayed as additional three bars on
the spectrum graph. Parameters for Total values (e.g. filters) are set by default and cannot be changed.
Note: Total values for 1/1- or 1/3-octave analysis can be different from those obtained for
profiles (if the LEQ Integration was set as Exponential).
10.1 S
ELECTING
1/1 O
CTAVE OR
1/3 O
CTAVE FUNCTION
To select the 1/1-octave or 1/3-octave analysis function,
open the Meas. Funct screen, select the 1/1 Octave
( 1/1.&Dose ) or 1/3 Octave ( 1/3.&Dose ) position and
press <Enter> .
<ENT>
Note: The 1/1-octave and 1/3-octave analysis functions are optional and should be unlocked
by entering the activation code in the text editor screen, which is opened after first attempt to
select them. Once unlocked these options will be ready to use permanently.
10.2 C
ONFIGURING
1/1-
OR
1/3-
OCTAVE ANALYSER
10.2.1 General measurement settings for 1/1 and 1/3-octave analysis
– General Settings
Execution of 1/1- or 1/3-octave analysis depends on certain set of parameters, configured in the
Measurement section.
Averaging of results for each spectrum band is performed during the Integration
Period and is repeated the Repetition Cycles times. 1/1-octave and 1/3-octave
spectra are always saved as Summary Results.
The Integration Period and Repetition Cycles parameters are defined in the
General Settings list.