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soaked in clean water at room temperature for 24 hours. If the water temperature is
low, soaking time should be 48-72 hours.
(D) The sponge can not be allowed to get stained or moldy, otherwise it will consume or
produce oxygen. If stained or moldy, please replace it immediately (some back-up
sponges are included in the kit).
4.3
Sensor Cap
(A) The sensor cap is a key part of the optical DO probe. The surface coating of the cap
cannot be scratched or mechanically worn. Otherwise, the service life of the sensor
cap will be reduced or the probe will be damaged. Please pay special attention to it
when using the probe.
(B) The surface coating of the sensor cap cannot withstand high temperature, so the
optical DO probe can not be tested in water above 50
˚C/122˚F.
(C) If the surface of the sensor cap is contaminated, please do not use alcohol or organic
solvents to clean, otherwise it may damage the probe. It can be gently wiped with a
soft clean cloth. To disinfect the probe, immerse it in 3% hydrogen peroxide for 15 to
30 minutes and then rinse off with clean water.
(D) The sensor cap has a service life of more than 8000 hours. When the probe is not
being used, the service life will not be reduced, so the actual use time of the sensor
cap is far more than a year. The major factor affecting the service life of the sensor
cap is the surface coating being damaged under external force. So the key is to
protect the sensor cap from external damage.
(E) If the sensor cap is damaged or deteriorated, users need to purchase a new one.
Every new cap has a set of calibration codes which need to be input into the
instrument. The specific input method will be described in the instruction manual of
sensor cap.
(F) Users should not take off the sensor cap when it is not in use. Nor should one swap
the caps from different instruments. When being installed, the sensor cap must be
tightened, and the interior can not be contaminated or wet.
5
Preparation for Calibration
5.1
Dissolved Oxygen Units Selection
Dissolved oxygen units displays in two forms: mg / L and %, and ppm and %. Press
to
switch between mg / L → %, or ppm → %. Users can choose mg / L or ppm in parameter
setting P3.1, but only a percentage (DO %) is displayed in calibration.
