Percent Air Saturation
Appendix J
YSI Incorporated
Environmental Monitoring Systems Operations Manual
J-3
%Local” values. For example, assume that the temperature of the calibration standard is 21 C (where air
saturation at 760 mm Hg is 8.915 mg/L) and that the oxygen content of the solution has been determined to
be 7 mg/L by Winkler titration. Assume also that the local barometric pressure was entered as 700 mm at
the last “DOsat %” calibration. After the new “DO mg/L” calibration, the “DO mg/L” value will be set to
7.00, the “DOsat %” value will be set to (7/8.915)*100 = 78.5, and the “DOsat %Local” will be set to
(760/700)*78.5 = 85.2.
NOTE:
As pointed out above, it is important to realize that UNLESS THE BAROMETRIC PRESSURE IS
KNOWN FOR EVERY DO READING AFTER CALIBRATION, the values of “DOsat %” and “DOsat
%Local” will be incorrect if the barometric pressure has changed since calibration. Thus, even if the
barometer had been input at the time of a mg/L calibration (a method used by some instrument
manufacturers, the values of “DOsat %Local” will still not be exactly accurate after calibration.
Activation of the “DOsat %Local” or “ODOsat %Local” Parameter
On receipt of your sonde or after upgrading your 6-series software to Version 2.13 or higher, the “DOsat
%Local” or “ODOsat %Local” parameter will NOT appear in your Report menu. To activate the
parameter, it is necessary to exit the menu structure of the sonde software to the command line prompt
(“#”). The “#” sign appears after you press
Esc
from the Main menu and then answer “Y” to the question,
“Exit menu (Y/N)”? Once the “#” prompt is shown on the display, type “dolocal 1” as shown in the
display below and press
Enter
. The screen will show “OK” to indicate that the action was successful and
return another “#” sign as shown. Then type “menu” at the second “# sign and press
Enter
to return to the
sonde software menu structure.
After taking the above action the parameter “DOsat %Local” or “ODOsat %Local”, depending on the type
of DO sensor used in your sonde, will be present in your Report menu. If you want to remove the
parameter, return to the “#” prompt, type “dolocal 0”, and press
Enter.
Summary of Contents for 6 series
Page 195: ...650 MDS Section 3 YSI Environmental Monitoring Systems Operations Manual 3 65 ...
Page 196: ...650 MDS Section 3 YSI Environmental Monitoring Systems Operations Manual 3 66 ...
Page 345: ...PAR Sensor Appendix K YSI Incorporated Environmental Monitoring Systems Operations Manual K 4 ...