YSI 6200 - Manual (Page 91)

YSI 6200 DAS USER Manual
YSI/Massachusetts 508.748.0366, Fax 508.748.2543 Page 8-10
Figure 8.9 Saving, Exporting, Printing and Related Functions
8.7 Example of Customizing a Subset of SAMPLE.DAT
Using SAMPLE.DAT we decided that some of the data were not of particular interest, so using
top line menu item Setup, then Parameters, then Add/Remove.., we removed ORP and Depth
results from the data set (see figure 8.10). Note that we have not deleted this information from
the file, but rather we are choosing not to display it. You can always return to this function and
add original data back. Under the same Parameters function, we have selected Attributes… and
changed the
Average Interval from the default 0 to 60. Since data was collected every 15 minutes, the change
to a 60 minute interval helps to smooth out the graph and average out any short term “noise”
events.
Next, we again select Setup, then Graph. From the functions available, we first selected Title
Page… and typed in a name (Clear Lake Study #2) and below that we typed the parameters that
are shown in the graph. Just below Title Page…, we clicked on 2 Traces per Graph. This
combines adjacent parameters which is sometimes useful in parameter and event evaluation. For
example, in the second graph shown in Figure 8.10 below, you see that DO concentration and pH
seem to track rather closely and change in a diurnal rhythm. In actuality, when DO levels drop in
a natural body of water, CO
2
often builds up forming carbonic acid which leads to lower pH