Since
the probe is sensitive, a series of maintenance procedures
are recommended to guarantee accurate measurements.
The electrolyte solution must be maintained at a set
level and it has to be replaced periodically. When
replacing the electrolyte solution, the probe must
be polarized to eliminate any residual oxygen that
may still be present in the cell.
The duration of the polarization process can vary
from a few minutes to several hours depending on the
instruments, and it is one of the factors that differentiate
this type of instrumentation. Hanna Instruments' oxygen
meters complete the polarization process in approximately
6 minutes, ranking amongst the fastest in the industry.
It is important to avoid trapping air bubbles when
the cap is screwed onto the probe. The Teflon® membrane
must be carefully checked, and in case of scratches,
tears or perforations, it should be replaced. It is
recommended to periodically calibrate the meter in
air to reset the 100% values (and in zero oxygen solution,
where appropriate).
By following these simple suggestions, your meter
will always remain accurate and reliable.
It
is crucial to the performance of your D.O probe to
keep the sensor active with regular maintenance. For
this purpose, Hanna has developed HI 7041S
electrolyte solution to refill the membrane cap.