7
•
WK-21 ½” measurement microphone (manufacturer: SONOPAN).
Other accessories specified in chapter 1.1 are optional.
1.4. Measured quantities
Many quantities used to characterize acoustic noise can be measured simultaneously using
DSA-50 digital sound analyzer. The set of measured quantities depends on instrument operating
mode. Measurement duration and battery condition information is displayed at every operating
mode.
1.4.1. Sound level meter (SLM) mode
For two frequency weightings, selected among from three ones: A, C and Z available in the
instrument, following quantities can be measured simultaneously (in symbols listed below X stands
for selected frequency weighting):
•
L
XF
current RMS, F-time-weighted sound level,
•
L
XFmn
minimum RMS, F-time-weighted sound level,
•
L
XFmx
maximum RMS, F-time-weighted sound level,
•
L
XS
current RMS, S-time-weighted sound level,
•
L
XSmn
minimum RMS, S-time-weighted sound level,
•
L
XSmx
maximum RMS, S-time-weighted sound level,
•
L
XI
current RMS, I-time-weighted sound level,
•
L
XImn
minimum RMS, I-time-weighted sound level,
•
L
XImx
maximum RMS, I-time-weighted sound level,
•
L
XPk
current peak sound level,
•
L
XMPk
maximum peak sound level,
•
L
Xeq
time-average (equivalent continuous) sound level,
•
L
Xeq1s
time-average sound level for last one second.
If A frequency weighting is one of two selected weightings, then following quantities are
measured additionally for this weighting:
•
L
AE
sound exposure level,
•
L
AEX,T
noise exposure level referred to specified exposure time T.
1.4.2. 1/1-octave analyzer mode
1/1-octave analyzer contains nine digital octave-band filters having exact centre frequencies
specified for binary octave ratio. Nominal centre frequencies are 31.5Hz, 63Hz, 125Hz, 250Hz,
500Hz, 1kHz, 2kHz, 4kHz and 8kHz. Specifications of filters conform to Class 1 requirements of
EN 61260:1995 and EN 61260:1995/A1:2001.
Following quantities can be measured simultaneously for each filter centre frequency (and also
for wide-band response), when one frequency weighting is selected among from three available
weightings (A, C and Z):
•
L
F
current RMS, F-time-weighted sound level,
•
L
S
current RMS, S-time-weighted sound level,
•
L
eq
time-average sound level.
If A frequency weighting is selected, then following quantities are measured additionally:
•
L
ASmx
maximum RMS, A-frequency-weighted, S-time-weighted sound level,
•
L
Aeq
time-average A-frequency-weighted sound level,
•
L
CMPk
maximum peak C sound level.
1.4.3. 1/3-octave analyzer mode
1/3-octave analyzer contains twenty nine digital 1/3-octave band filters having exact centre
frequencies specified for binary octave ratio. Nominal centre frequencies are 25Hz, 31.5Hz, 40Hz,
50Hz, 63Hz, 80Hz, 100Hz, 125Hz, 160Hz, 200Hz, 250Hz, 315Hz, 400Hz, 500Hz, 630Hz, 800Hz,