Norsonic nor118, Instruction Manual, Page: 48 / 116

36 Chapter 6
Basic time profile measurements
37 Norsonic Nor118
User Guide
The measurement duration setup menu
The profile resolution does not have to be selected so
that the global duration becomes a multiple of the profile
resolution. The last period will be truncated if the duration
divided by the profile is not an integer.
Total (global) duration
of measurement.
Selected resolution
No. of periods with
selected duration and
resolution
Max. No. of periods
(depends on the amount
of free memory avail-
able)
The time profile display
Pause and profile
Here, the instrument is in pause mode. Global acquisition
is halted, but the profile is still acquiring data. The thin line
below the graph represents a marker associated with the
periods acquired while paused. The meaning of the line
below the graph is given by the text: Mk: P which should
be interpreted as Marker: Paused to indicate that these
data will not be a part of the global level assessment.
The
∆
indicates
profile (global is
indicated by a
Σ
)
Graph cursor.
Use
keys to move
the cursor along
the graph. This
feature is not
available during
a measurement
Display top scale
Spectral weight-
ing function
applied to the
graph
Measurement
running
Value at cursor’s
position
Which resolution should you use?
is will always be a trade-off between
the need for information and the amount of data
generated. You should also take into consideration
the global duration of your measurement.
For example, you may want a higher resolution in
a 1 minute measurement than in a 24 hour measure-
ment. Will you need a 1 second resolution for 24
hours? It’s going to be a lot of information to go
through afterwards.
No absolute rules or guidelines can be given since
there are so many different applications and require-
ments. However, we address the issue to remind you
of the need to consider it when setting up for profile
measurements.