WPI APOLLO 4000, Instruction Manual

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APOLLO 4000
OXYGEN DETECTION
World Precision instruments d-
Care of the Electrode
the reduction of oxygen and other trace impurities causes a decrease in the
surface activity of the working electrode. this phenomenon is referred to as
“poisoning”, and over time has the effect of gradually reducing the electrode’s
capability to generate a sufficient redox current. As such, it is recommended to use
the following guidelines to maximize the life of the electrode:
if the oxygen electrode is being used on a daily basis, it’s recommended that the
instrument be left on with the electrode connected to maintain polarization (see
“Polarization” on page d-2). However; if the electrode is not to be used for a period
of more than 2-3 days, it’s recommended that the electrode be disconnected from
the instrument, and stored with the tip immersed in distilled water. this practice
will reduce the possibility of a gradual reduction of electrode surface activity (as
discussed above) under long term polarization. if the electrode will not be used for
a long period of time (several months), refer to the section titled “storage” below.
Handling Precaution
When passing the o
2
probe through small holes, gaskets or o-rings, allow
sufficient clearance so that the probe tip is not damaged by abrasion. the probe
tip should slide through openings easily before sealing the probe shaft to assure
an air-tight fit.
Storage
For long term storage (several months) unscrew and remove the sleeve from the
probe handle, rinse the electrode tip and the sleeve with distilled water. When
both are dry, replace sleeve to protect probe wand but do not screw the sleeve
completely onto the handle.