Cirrus Optimus Green Series, Руководство по прибору

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Optimus sound level meter - instrument handbook
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5.1.3 Leq view
Shows you the Leq, Peak, LAE (SEL) and C-A values with a choice of A, C or Z frequency
weightings.
The C-A data can be used with the HML method for selecting hearing protection.
If the time weighting is set to Impulse, the C-A function is replaced by LAeq,I (also
known as LAIeq).
When the instrument is set to the German language, an additional ‘Taktmaximal’ page
is also available.
5.1.5 1:3 Octave band view
This view shows the noise levels divided into 1:3 octave (called ‘third-octave’) frequency
bands. This view can be used for environmental noise measurements and also for noise
control applications.
The 1:3 octave band view also provides Leq,LF (20 - 200 Hz) and LAeq,LF (20 - 200 Hz).
5.1.6 Tone detection
This is a capability displayed within the 1:3 octave view on some instruments.
Instruments with tone detection use either the ISO 1996-2:2007 simplified method or
an improved method developed by Cirrus Research, which is based on the ISO standard,
extended to include tones between bands, tones in outer bands and Z-weightings. The
ISO method only applies to overall data when measuring or reviewing, whereas the
Cirrus improved method also applies to instantaneous live values.
When a tone is detected, the band is highlighted in blue on both the graphical and
numerical pages.
The tone detection method can be set to either the Cirrus improved method (default
setting) or the ISO 1996 method in NoiseTools.
For more information, please see Technical Note 32 – Tonal noise detection with the
Optimus sound level meters, available for download from the Cirrus Research website
at www.cirrusresearch.co.uk/library/user-manuals/.