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5.4.
Calibration
5.4.1.
Zero Calibration
Select
Probe Calibration
from the screen shown in figure 6. Select
Zero cal
. Establish the zero calibration
gas (Pyxis DCC-3 Cylinder = 99.9999% Nitrogen Gas) flow for 15 minutes or until the ppb reading to be
stablized. Press OK on the
Zero cal
to start the zero calibration. If the zero calibration is complete, a
calibration succeed message will be prompted.
Figure 8. Zero Calibration
Figure 9. Zero Calibration waiting
5.4.2.
Slope Calibration
Select
Probe Calibration
from the screen shown in figure 6. Select
High cal
. Establish an oxygen containing
calibration gas (Pyxis DCC4 = 99.9% Nitrogen / 0.1% Oxygen Gas Cylinder) flow for 15 minutes or until the
ppb reading has stablized. Press OK on the
High cal
to start the slope calibration. Use the up/down button
and OK button to focus on the oxygen percentage value. Use the up and down button to change this value
to the oxygen percentage concentration in the calibration gas being used. If the slope calibration is
complete, a calibration succeed message will be prompted.
*NOTE*
- the value shown in figure 10 is the oxygen percentage in the calibration gas, not the dissolved
oxygen concentration in ppb or ppm. The ST-774 probe will automically convert the oxygen percentage
concentration along with the measured barometric pressure and temperature to the precise dissolved
oxygen concentration in ppb or ppm during the calibration process.
