BATTERY REPLACEMENT
When the battery is rundown
"V" is displayed on the Liquid
Crystal Display to warn the
user.
This is to inform the user that the display will be
shut-off after about 4 hours of use to prevent
erroneous measurements being taken due to
low voltage.
Battery replacement must only take place in a
non hazardous area using alkaline 1.5 V AA
type batteries.
In order to replace run-down batteries, simply
remove the two screws on the rear cover of the
instrument and replace the four 1.5V AA batter-
ies with new ones, paying attention to the
correct polarity (refer to #1 in the Functional
Description page 5).
V
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•
Make sure that the rubber O-ring is seated
properly inside the membrane cap.
•
With the sensor facing down, screw the
membrane cap clock-wise. Some electro-
lyte will overflow.
The Platinum cathode (#8 in the Functional
Description at page 4) should always be bright
and untarnished. If it is tarnished or stained,
which could be due to contact with certain
gases or extended use with a loose or damaged
membrane, the cathode should be cleaned. You
can use a clean lint-free cardboard or cloth. Rub
the cathode very gently side to side 4-5 times.
This will be enough to polish and remove any
stains without damaging the platinum tip. After-
wards, rinse the probe with deionized or distilled
water and install a new membrane cap using
fresh electrolyte and follow the steps above.
Recalibrate the instrument.
Important: in order to have accurate and stable
measurements, it is important that the surface
of the membrane is in perfect condition. This
semi-permeable membrane isolates the sensor
elements from the environment but allows oxy-
gen to enter. If any dirt is observed on the
membrane, rinse carefully with distilled or deion-
ized water. If any imperfections still exist, or any
damage is evident (such as wrinkles or tears -
holes), the membrane should be replaced.
Make sure that the O-Ring is properly seated in
the membrane cap.
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