Do cal (manual) – YSI 5000 User Manual
Page 24
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21
DO Cal (manual)
1. Prepare the probe according to the probe instructions.
2. Connect the probe to the meter.
3. Place the probe in a known oxygen environment, such as a BOD bottle containing about 1
″
of
water to provide a 100% relative humidity environment or a Winkler-titrated sample.
4. Press [ ] to turn the instrument on.
5. Allow the probe to polarize and the temperature to stabilize for at least 15 minutes. If
calibration is performed prematurely the values will drift and may be out of specification.
6. Press the [CALIBRATE] soft-key to change to Calibration mode. The following screen will
be displayed.
98.0
*
% 8.15
mg/L
Calibrate
0.0
ppt
740
mmHg
24.38°C 11:33
AM
AUTO CAL
DO CAL
SETUP
DIAGNOSTICS
7. Press the [DO CAL] soft-key to enter the manual DO calibration menu.
98.0
*
% 8.15
mg/L
Cal %
0.0
ppt
740
mmHg
24.38°C 11:33
AM
UP
DOWN
DIGIT
NEXT
8. Make sure that the display readings are stable, then enter the calibration value in percent
saturation, using the [UP], [DOWN] and [DIGIT] soft-keys. See Appendix A - Oxygen
Solubility Table and Appendix B - Pressures and Altitudes for manual calibration data.
If you wish to calibrate in milligrams per liter (instead of percent), verify that the salinity is set to
the salinity value of the calibration environment (0.0 ppt for air calibration, see 6.1 Dissolved
Oxygen Calibration, Salinity). Then, use the [NEXT] soft-key to select mg/L and enter the
calibration value in milligrams per liter as shown below.
Flashing digit