Norsonic nor140, Instructional Manual

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6 6
Introduction
Recording the sound
The instrument may be set up to record the sound
during a measurement facilitating easy identification
of a noise source. The start of the recording may be
triggered by the noise event, an external command or
started by pressing the
RECORD
button.
Different formats for the recording may be selected
to balance the requirements to signal quality and
memory usage.
Excellent for noise monitoring
With the Nor140 you are able to do nearly all types
of noise measurements – community noise, industrial
hygiene, product control, noise mapping and more.
But, you don’t need to attend the measurement
sessions all the time. In fact, the Nor140 is able to do a
lot on its own.
The measurement time can be preset to e.g. 30
minutes or an hour and the instrument put in a mode
where it measures and stores the results, then starts
measuring again, stores the results, starts measuring
again and so on. Each measurement will be stored
in a separate file, but all files are stored in the same
directory, which has the name of today’s date.
In this way the instrument will measure the periods
you need. And if this store and go feature (which is
standard) is combined with the optional time profile
each measurement will provide global data and a time
profile with a resolution specified by you!
Of course, the instrument will spend a little time
storing the data (housekeeping). Therefore, if you start
the session with hourly measurements exactly on the
hour, long “store and go” sessions will – after a while
– experience a small, but significant time shift, so that
each period no longer starts exactly on the hour.
Enter
synchro mode
. This feature (standard in
all models) stops the measurement on the hour and
restart the next measurement a couple of seconds
later to provide time for storage. By sacrificing a
little at the start of a measurement, the synchronisation
with the time of day is retained - a feature important to
many of our customers.
The principle of optional extensions
The capabilities and setup options of your Nor140 will
depend on which of the available extensions it has
been equipped with.
Extensions are modules – made as software, in the
instrument or e.g. as software for your PC – available
for your Nor140. Norsonic extensions are always
optional and hence often referred to as options. In
this way you do not have to pay for features you’re not
going to use.
However, you may find that your tasks are expand-
ing into new areas of acoustics as time goes by. There-
fore a typical Norsonic extension will be available for
installation as retrofit.
The optional extensions may enhance the operation
of the instrument considerably. Normally these types
of options are called modes of operation. Such
extensions may be transferring the instrument to an
FFT-analyser, an analyser for speech transmission
index, or a building acoustic analyser for the
measurement of sound insulation including
measurement of the reverberation time.
Transducers
Nor140 is normally equipped with microphone Nor1225
and preamplifier Nor1209. Other types of transducers
may be connected to the input socket – directly or by
suitable interface and/or power supply. Pre-polarised