LaMotte 1761 Manual - page 11
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4. Moisten the sponge in the electrode cap with distilled water or tap water.
Do not soak the sponge.
5. Replace the electrode cap on the electrode. There must be an air gap
between the membrane and the sponge.
6. Wait until the reading stabilizes. Press and hold CAL until ‘CAL’ is
shown on the display. The readings will blink ‘101.7’ and ‘SA’ will
appear. ‘SA’ will not appear if the calibration fails.
7. When the calibration is complete ‘End’ will appear and the meter will
return to the measurement mode.
Optional Zero Oxygen Calibration
The zero oxygen calibration will improve the measurement accuracy for very low
or very high dissolved oxygen samples.
1. Place the electrode in a zero dissolved oxygen calibration solution, such
as 5% sodium sulf te.
2. Slowly stir the sample with the electrode and wait for the reading to
stabilize. This may take a while, depending on the electrode history.
3. Press CAL until ‘CAL’ is shown on the display. The readings will blink
‘101.7’ and ‘SA’ will appear. ‘SA’ will not appear if the calibration fails.
4. When the calibration is complete ‘End’ will appear and the meter will
return to the measurement mode.
NOTE: Sodium Sulf te can become deposited on the electrode and on
the coined surface of the electrode retaining collar. The presence of the
Sodium Sulf te will negatively affect dissolved oxygen measurements
unless it is removed completelyfrom the electrode.
CALIBRA
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