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Averaging: press this button repeatedly to switch averaging between 1 second (no
averaging), 10 seconds, 1 minute, 10 minutes or 1 hour. Note that the averaging is
performed on the stage signals, and not on the computed values (number, diameter,
LDSA). Because the computations are nonlinear, this is not the same as averaging the
computed values - just as <x2> is not equal to <x>2
View all: By default, the data analysis tool doesn‘t display values measured during the
hourly one-minute offset measurement. Press this button to see those values too.
Zoom out: zoom out from the graph to view the entire data set. To zoom in on the graph,
select an area on the graph with the mouse.
Filter: displays the
fi
lter stage signal over time in the graph panel
Diffusion: displays the diffusion stage signal over time in the graph panel
Corona voltage: displays the corona high voltage over time in the graph panel. Press
again the button to display the charging current over time in the graph panel.
Zero offsets: displays the zero offsets over time in the graph panel. Check this if you are
not sure whether the zero offsets were stable or if a warning on unstable zero offsets
appears when you load a
fi
le.
Temperature: displays the instrument temperature over time in the graph panel
Flow: displays the
fl
ow in the instrument over time in the graph panel. Note that this is
not actual
fl
ow in l/min, but the signal from the
fl
ow sensor.
Data adjustment software options
• If you have rapidly changing aerosol concentrations, the induction correction can give improved results
(see software section). Switch to the diameter display, and check the look of the data with and without
induction correction. If over- and undershoots during rapid transients are reduced with the induction
correction, then use it, otherwise do not use it, because it adds some noise to the diffusion stage signal
• Use the averaging option to reduce the number of data points if necessary
• Use the “time since midnight” in the software option menu to get seconds since midnight rather than
second-since start, if useful (to align data of multiple runs/instruments).
• Use the “align averages” option to align averaged values if this is useful to you. For example, for hourly
values, this option will give you averages between full hours rather than averages over the first 3600 se-
conds. Be aware that you will lose the first noncomplete hour of data (i.e. if you start measuring at 10:30,
your first data point will be the hour between 11:00 and 12:00).
• Export the data for further analysis in your favorite program (Excel, Igor, Origin etc)
