Svantek Shawcity SVAN 977C, Руководство пользователя

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93 SVAN 977C User Manual
10 1/1- AND 1/3-OCTAVE ANALYSER
The instrument operates as a real-time 1/1-octave or 1/3-octave analyser in a very similar way to the level meter.
Moreover, 1/1-octave or 1/3-octave analysis is performed in parallel with the level meter measurements. All
digital pass-band filters (16 1/1-octave with centre frequencies from 31.5 kHz down to 1.0 Hz and 48 1/3-octave
with central frequencies from 40 kHz down to 0.8 Hz; in the base ten system) are working in real-time with the
weighting filters (
Z , A , B , C , HP or HPE ) and the RMS/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 RMS, 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 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 RMS/LEQ results are measured with their own weighting filters (A, C and Z - for sound
measurements; HP, HP3 and HP10
– for vibration measurements) regardless of settings made in the
profiles for the Level Meter. Total values for 1/1-octave or 1/3-octave analysis can be different from
those obtained for profiles (if RMS 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
Measurement Function screen, select the
1/1 Octave or 1/3 Octave position and
press <ENTER> .
<ENT>
Note: The 1/3 Octave function is optional and should be unlocked by entering an activation code in
the text editor screen, which is opened after first attempt to select this option. Once unlocked this
option will be ready to use permanently.
Note: It is not possible to change the current function during a running measurement.
In this case, the instrument displays for about 2 seconds the message:
“Measurement in Progress”.
To change the current function, the measurement must be stopped!