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1. Bottom cover of the calibration sleeve
5. Locking cap
2. Sponge for water storage
6. Optical DO electrode
3. Sensor cap
7. O-ring
4. Calibration sleeve
Immersion line: The tested solution should be above this line
4.2
Probe maintenance
The sensor cap of the optical DO electrode must be kept in a moist environment. If the surface coating of
the sensor cap dries out, the reading will be unstable, or the response rate will be slow.
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Before the first use, unscrew the bottom cover of the calibration sleeve to check if the sponge is
damp. If the sponge is dry or if the electrode is exposed in dry air for more than 8 hours, the surface
coating of the sensor cap may be completely dried and needs to be hydrated. Soak the electrode in
tap water at room temperature 77°F(25°C) for 24 hours. If the water temperature is low, soaking time
should be 48-72 hours.
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Short-term storage (less than 30 days): Keep the probe head in the calibration sleeve. Always keep
the sponge inside the calibration sleeve moist. Several drops of clean water should be added to a dry
sponge (let the sponge be damp, but not dipping), and tighten the lock cap, so that the sensor cap is
kept in the moist-saturated air.
⚫
Long-term storage (greater than 30 days): Keep the probe head in the calibration sleeve. Check
whether the storage sponge is moist every 30 days or user can store the electrode in a beaker
containing clean water.
⚫
The sponge cannot be allowed to get stained or moldy, otherwise it will consume or produce oxygen.
If stained or moldy, please clean it or replace with new sponges immediately.
Diagram- 9
