Norsonic nor140, Instructional Manual, Page: 23 / 220

5
Norsonic Nor140
Instruction Manual
5
Norsonic Nor140
Instruction Manual
For the global analysis the functions measured are
the instantaneous SPL, the maximum and the minimum
SPL, the equivalent level, the sound exposure level
and the maximum peak level. All levels are measured
as A-weighted and Z- or C-weighted levels.
The time profile logs the A-weighted equivalent
level, the A-weighted maximum sound pressure level
and the Z- or C-weighted peak level.
The enhanced profile option.
In need of even better
resolution or better control of the functions measured?
No problem! The time profile extension can be expanded
into the enhanced profile extension – our option 7 for
the Nor140. Order it when you purchase your Nor140
or later, if that suits you better.
In the enhanced mode, the instrument logs the time
profile of the same functions as with the global:
• SPL The Instantaneous Sound Pressure Level
• L
MAX
The Maximum Sound Pressure Level
• L
MIN
The Minimum Sound Pressure Level
• L
eq
The Integrated Equivalent SPL
• L
E
The Sound Exposure Level
• L
PEAK
The Maximum Peak Level
If you then add the option 5, parallel time constants,
you may set up the instrument to log any combination
of functions and time constants, for example the SPL
with S time constant and the maximum SPL with F time
constant simultaneously.
Enhanced time resolution as well.
The enhanced
profile has a time resolution which can be from 50 ms
and upwards in 25 ms steps (in 1 second steps above
1 second time resolution), so beware unless you want
to create a busy day for yourself – there will easily be
quite a lot of data generated, so avoid more details than
strictly needed!
Multispectral measurements
The Nor140 functionality can be expanded to include
multispectral measurements. This extension takes the
instrument’s time profile capabilities to new heights by
allowing complete spectra to be logged as a function
of time.
Source coding
Have you ever made a measurement where you later
found out that you desperately need to know what
caused the level to be what it turned out to be?
Enter
source coding
. With the enhanced profile
option you may tag or code sources as they happen. A
one digit code (which appears in the display as 1~4) is
entered to later serve as an identification of the type of
noise. This can also be referred to as adding a marker
to the measurement.
For example, in a traffic noise measurement, a bus
passing may be identified by the digit “1”, while trucks
may be identified by “2”, unexpected vehicles by “3”
etc. In the profile display the markers appear as dots
or lines below the graph. If you move the time cursor
onto such a dot, the marker type (i.e. its number) will
appear in the display.
During a measurement, adding any of the markers 1,
2 and 3 will assign the corresponding marker number
to the current period only. Adding marker number 4,
however, will assign this marker to the current period
plus all consecutive periods until the marker again is
deactivated. A typical application for marker 4 is to
denote intervals of particular interest.