Svantek SV 104BIS, Руководство пользователя

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SV 104BIS User Manual
The instrument can also operate as a real time 1/3-octave band analyser (RTA). In addition, and if enabled,
1/3-octave analysis is performed in parallel with the dosimeter operations. All 1/3-octave digital pass-band
filters (with 28 centre frequencies from 10 kHz down to 20 Hz; in base 10 system) are working in real-time with
the broadband frequency weighting filters (Z, A or C) and the linear LEQ detector. This enables the user to
pre-weight a spectrum with one of the selected broadband frequency curves if required for a particular
application such as the provision of hearing protectors in the control of high workplace noise levels.
Note: The three overall TOTAL LEQ results are measured with the weighting filters (A, C, Z) without
taking into account the settings of the level meters for profiles. The spectra are always linearly
averaged. Thus, the TOTAL values from 1/3-octave band analysis can be different from those
obtained for the profiles (if the LEQ Integration was set as Exponential).
The results of 1/3-octave analysis (so-called spectrum) can be examined by the user on a display in Spectrum
VIEW presentation mode. 1/3-octave spectra for all 28 centre frequencies of pass-band filters together with
the 3 TOTAL overall values measured with the user selected frequency weighting filters are presented in the
Spectrum mode, if enabled in the configuration setup. Spectrum cursor can be moved left and right with the
and keys respectively.
With the use of the Supervisor software, the user can select which spectrum ( LEQ , MAX or both) will be
available for view (Chapter 6.3.7 ).
Figure 3-16 1/3-octave analysis LEQ spectrum plot view
Figure 3-17 1/3-octave analysis MAX spectrum plot view
current
centre
frequency
current
Total LEQ
weighting filter
value of the
spectrum
at cursor
position
weighting
filter
cursor
current
centre
frequency
current
Total Lmax
weighting filter
value of the
spectrum
at cursor
position
weighting
filter
cursor