Accumet XL 20 User Manual page 149

Automatic standardization at two points—% Saturation
For this standardization, the 0% saturation must be the first point followed by 100% saturation.
The meter will accept readings below 5% saturation for 0% saturation standardization and
between 30 and 200% saturation for 100% saturation (at 760 mm Hg).
1. Touch Standardize on the DO measure screen to access the standardize screen.
2. If the screen says "Not standardized" proceed to step 4.
3. Touch Clear if you need to delete the previous standardization values.
4. Insert DO probe into a bottle containing 0% saturation solution.
5. Allow probe to stabilize for 30 minutes, constantly stirring the solution.
6. The screen will flash a 0% beaker icon. When the reading is stable, STABLE appears on
the screen. Touch Confirm to standardize. The meter will then return to the DO measure
screen.
7. Touch Standardize on the DO measure screen to access the standardize screen.
8. Insert DO probe into a BOD bottle filled with 1 inch of water to provide a 100% relative
humidity environment.
9. Allow probe to stabilize for 30 minutes.
10. The screen will flash a 100% beaker icon next to the 0% beaker icon. When the reading
is stable, STABLE appears on the screen. Touch Confirm to standardize. The meter will
then return to the DO measure screen.
Once meter is calibrated DO Measure screen shows the standards, the time/date of last
standardization and AUTO standard recognition.
DO Operation: Standardizing
XL40 and 60 meters
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