SVAN 948 USER MANUAL
4 - 1
4. MEASUREMENT FUNCTIONS OF THE INSTRUMENT
The SVAN 948 is a unique pocket 4-channels instrument combining functions of a sound level
meter (SLM), with the Type 1 accuracy (according to IEC 651, IEC 804 and IEC 61672-1 standards), a
vibration level meter (VLM), 1/1 OCTAVE and 1/3 OCTAVE real time analyser in which in parallel
operate the digital pass-band filters. The values of the central frequencies of these filters are defined in
the sequence conforming to the base two system. All 1/1 octave & 1/3 octave filters are Type 1 (according
to IEC 1260 standard).
The narrow-band frequency analysis (FFT) is also available in this instrument as option.
Thanks to the application of the state of digital signal processing, in the instrument works in four
independent sound / vibration level meters channels, so-called here channels, which perform the
measurement of the signal with the selectable combination of:
• A, C, LIN (Z) (conforming to IEC 61672-1 standard) weighting filters and SLOW, FAST or IMPULSE
RMS detectors - in the case of sound and
• HP1, HP3, HP10, W–Bxy, W–Bz, H–A, W–Bc, KB, Wk, Wd, Wc or Wj weighting filters and 100 ms,
125 ms, 200 ms, 500 ms, 1 s, 2 s, 5 s or 10 s RMS detectors - in the case of vibration.
1/1 OCTAVE, 1/3 OCTAVE or FFT analyser works simultaneously with the mentioned above
channels.
In the case of acoustic signal the measurement of SPL, LEQ, SEL, Ld(en) (depending on the
period of the measurement d-day, e-evening, n-night the different abbreviations of the function name are
displayed), Ltm3, Ltm5, LN (statistics), PEAK, MAX, MIN and time history are performed simultaneously
in all channels (cf. Appendix D.1.1 for the definitions).
In the case of vibration signal the measurement of RMS, VDV, PEAK, P–P, MTVV, MAX and time
history are performed simultaneously in all channels (cf. Appendix D.1.2 for the definitions).
The measurement results can be presented on the display of the instrument in the different ways
depending on the selected function and the setting of the parameters. In the case of the sound / vibration
level meter the following display modes (the ways of the measurement results presentation) are available:
• One Profile, 3 PROFILES, STATISTICS and PLOT.
• In the case of 1/1 OCTAVE, 1/3 OCTAVE or FFT analysis the possibility of the spectra
presentation is also available (SPECTRUM mode).
• The selection of the display mode is made by pressing the <
> or <
> push-button.
• The switching between the channels is possible by pressing the <SHIFT> and <
> or
<SHIFT> and <
> push-buttons (in one profile, 4 PROFILES or STATISTICS modes).
• The switching between the results in the selected channel is made by pressing the <
>,
<
> push-buttons (in one profile or 3 PROFILES modes).
• The changing of the statistics class (statistics are available only for sound measurements),
1/1 octave or 1/3 octave filter, the FFT line and the value in the buffer is done by pressing the
<
>, <
> push-buttons (the movement of the cursor in STATISTICS, SPECTRUM and PLOT
modes).
• The pressing of the <SHIFT> and <
> or <SHIFT> and <
> push-buttons enables the user to
change the relation between the vertical and horizontal axis for the SPECTRUM and PLOT
modes of result’s presentations.
• In the case of 1/1 OCTAVE or 1/3 OCTAVE analysis mode of acoustic signal, pressing the
<ENTER> push-button in the SPECTRUM mode of result’s presentation enables the user to
observe on the display the statistical analysis performed for the selected 1/1 OCTAVE or
1/3 OCTAVE filter. The return to the SPECTRUM mode is made after pressing the <ESC>
push-button. The statistical analysis is not performed for the vibration signal, so nothing occurs
in this mode after pressing <ENTER> push-button in the SPECTRUM mode of result’s
presentation.
To Next Page
Loading...