Hanna Instruments HI 4010 - Manual (Page 7)

7
•
A slightly scratched crystal may benefit from a treat-
ment with a fluoride containing toothpaste (without
baking soda). Lightly wipe the sensor tip with the
mild abrasive. Rinse well with deionized and soak in
a fluoride standard near measurement value.
•
Avoid large changes in temperature (thermal shock)
as it may damage the sensor.
HI 4010
•
Remove protective cover from sensor tip.
HI 4110
•
Remove the protective plastic wrap that covers the
ceramic junction before assembling sensor for the first
time.
•
Ensure o-ring is installed on sensing module before
screwing into the inner stem.
O-Ring
•
Add reference HI 7075 fill solution daily to maintain
a good head pressure. For optimum response, this
level should be maintained and not be allowed to
drop more than 2-3 cm (1-inch) below fill hole.
•
During measurement always operate electrode with
the fill hole open.
•
During normal use, fill solution will slowly drain out
of the tapered cone junction at the lower portion of the
electrode. Excessive loss (>4 cm drop within 24 hours)
is not normal. If this occurs verify cap is tightened and
the interface between the internal cone and outer
body is free of debris.
•
If an erratic measurement occurs, check to see if for-
eign matter is seen trapped near the internal cone.
Drain and refill with fresh fill solution.