Hanna Instruments HI 98186 User Manual

Page 64

The oxygen probe is made of reinforced plastic for maximum durability. A
thermistor temperature sensor provides temperature measurements of the
sample. Use the protective cap when not in
use.
To replace the membrane or refill with electro-
lyte, proceed as follows:
Remove the protective cap by gently twisting,
and pulling and pulling it off the body of the
probe (see fig. 1).
Unscrew the membrane cap by turning it coun-
terclockwise (see fig. 2).
Wet the sensor by soaking the bottom 2 cm
(1’’) of the probe in electrolyte for five minutes.
Rinse the new membrane cap, supplied with
the meter with electrolyte solution while shak-
ing it gently. Refill with clean electrolyte solu-
tion.
Gently tap the sides of the membrane cap with
your finger tip to ensure that no air bubbles
remain trapped. Do not tap directly the bottom
with your finger, as this will damage the mem-
brane.
Make sure that the rubber O-ring sits properly
inside the membrane cap.With the sensor fac-
ing down, slowly screw the membrane cap clock-
wise. Some electrolyte will overflow.
The Platinum cathode (#8 in the Probe Func-
tional Description page 8) should always be
bright and untarnished. If it is tarnished or
stained, the cathode should be cleaned. You can use a clean lint-free card-
board 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.
Afterwards, 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.

PROBE MAINTENANCE