Hach PLATINUM Series, Руководство пользователя

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13
Introduction,
continued
1.3.2.2 Low Ionic Strength (LIS) Conditioning
(For measurements in samples of low ionic
strength, approximately 150 µS/cm or less):
Initial use: Before measuring a LIS sample, pre-soak the
electrode in a solution similar to the sample in ionic strength
and pH for 10 to 15 minutes. Remove the electrode from this
solution and click the reference electrolyte dispenser until gel
emerges from the tip. Rinse the electrode with deionized water
from a wash bottle. Blot excess liquid with a soft paper towel.
Place the electrode in the sample.
Between uses: Between uses, in intervals of up to a few hours,
the electrode can be stored in the sample (if not an extreme pH),
or in a neutral LIS solution such as tap water. Before measuring
a new sample, refresh the reference electrolyte gel by clicking
the dispenser until fresh gel emerges and carefully rinse the
electrode to prevent sample contamination.
1.4 Measuring Hints
These suggestions will improve the accuracy of your
calibration and sample measurement.
•
Dispense electrolyte if reading becomes unstable, erratic, or
if stabilization takes too long. An unstable reading may
also indicate an air bubble in the reference line. Remove the
electrode from the sample and invert it to view the
reference junction. Depress the dispenser button repeatedly
until the bubble is expelled (5 to 10 clicks should be
sufficient). Rinse with sample and blot to dry. Immerse the
electrode in the sample.
•
Allow the potential to stabilize completely
(<1 mV/minute drift) before accepting a calibration point
or sample reading. Meters set to higher resolutions will take
longer to stabilize than meters set to lower resolutions.
•
Use calibration standards and samples that are at the same
temperature to improve accuracy.
•
Use fresh calibration standards to achieve greater accuracy.