YSI ProODO - Manual (Page 15)

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display. Highlight the barometer value and press
enter to adjust it if needed. If the barometer
reading is incorrect, it is recommended that
you calibrate your barometer. Note - the
barometer should be reading “true” barometric
pressure (see Barometer section for more
information on “true” barometric pressure).
If the value is acceptable, there is no need to
change it or perform a barometer calibration.
Wait for the temperature and DO% values
under “Actual Readings” to stabilize, then highlight Accept Calibration and
press enter to calibrate. If User Field 1 or 2 are enabled, you will be prompted to
select the fields and then press Cal
to complete the calibration. The message
line at the bottom of the screen will display “Calibrating Channel...” followed by
“Calibration Successful”. Press Esc
to cancel the calibration.
CALIBRATING DO % IN AIR SATURATED WATER:
1-POINT CALIBRATION
Continuously sparge water with air using an air stone or some type of aerator
until the water becomes completely saturated with air. For 500 ml of water at
room temperature, it may take 60 minutes or more for the water to become
completely saturated . Place the sensor in the air saturated water, be sure to
immerse both the ODO and Temperature sensor into the water, and wait for the
readings to stabilize (at least 2 minutes).
Press Calibration . If Probe ID or User ID are enabled in the System GLP
menu you will be able to highlight these features and add, select, edit, or delete
an ID. When enabled these IDs are stored with each calibration record in the
GLP file.
After selecting the Probe ID and/or User ID if appropriate, highlight DO and
press enter. Highlight DO % and press enter to confirm.
The instrument will use the value from the internal barometer and will display
this value in brackets at the top of the display. Highlight the barometer value
and press enter to adjust it if needed. If the barometer reading is incorrect,
it is recommended that you calibrate your barometer. Note - the barometer
should be reading “true” barometric pressure (see Barometer section for more
information on “true” barometric pressure). If the value is acceptable, there is
no need to change it or perform a barometer calibration.
Wait for the temperature and DO% values under “Actual Readings” to stabilize,
then highlight Accept Calibration and press enter to calibrate. If User Field 1
or 2 are enabled, you will be prompted to select the fields and then press Cal
to complete the calibration. The message line at the bottom of the screen will
display “Calibrating Channel...” followed by “Calibration Successful”. Press Esc
to cancel the calibration.
CALIBRATING IN AIR SATURATION PERCENT (DO %):
2-POINT CALIBRATION WITH ZERO SOLUTION
Place the sensor in a solution of zero DO. Be sure to immerse both the ODO and
Temperature sensor into the water.
A zero DO solution can be made by dissolving approximately 8 - 10 grams of
sodium sulfite (Na
2
SO
3
) into 500 mL tap water or DI water. Mix the solution
thoroughly. It may take the solution 60 minutes to be oxygen-free.
Press Calibration . If Probe ID or User ID are enabled in the System GLP
menu you will be able to highlight these features and add, select, edit, or delete
an ID. When enabled these IDs are stored with each calibration record in the
GLP file.
After selecting the Probe ID and/or User ID if appropriate, highlight DO and
press enter. Highlight Zero and press enter. Wait for the temperature and
DO% values under “Actual Readings” to stabilize, then press enter to Accept
Calibration. If User Field 1 or 2 are enabled, you will be prompted to select the
fields and then press Cal
to complete the calibration. The screen will then
prompt for a follow-up second point calibration.
Highlight DO% for the second calibration point and press enter to continue with
the next point at full saturation. Rinse the sensor of any zero oxygen solution
using clean water. Follow the steps under either of the DO % Saturation methods
previously discussed to complete the second point.
CALIBRATING IN MG/L OR PPM AS A TITRATION:
1-POINT CALIBRATION
Place the sensor into a water sample that has been titrated by the Winkler method
to determine DO concentration. Allow the sensor to stabilize.
Press Calibration . If Probe ID or User ID are enabled in the System GLP
menu you will be able to highlight these features and add, select, edit, or delete