8 Maintenance
8.1 Meter maintenance
Never unscrew the two halves of the housing!
The meters do not require any maintenance other than an occasional wipe with a damp cloth. The
housing is made of acrylonitrile butadiene styrene/polycarbonate (ABS/PC). This material is sensitive
to some organic solvents, such as toluene, xylene and methyl ethyl ketone (MEK).
Any spillage should be wiped off immediately.
8.2 Electrode maintenance
Make sure the pH electrode is always kept filled with the appropriate filling solution.
For maximum accuracy, any filling solution that may have "crept" and encrusted the outside of the
electrode should be removed with deionized water.
Always store the electrode according to the manufacturer's instructions and do not allow it to dry out.
If the electrode slope falls rapidly, or if the response becomes sluggish, the following procedures may
help. Try one of the following, depending on your sample.
Problem
Fat or oil build-up
pH sensor membrane has dried out
Protein build-up in the diaphragm of a pH sensor Remove deposits by soaking the electrode in an
Silver sulfide contamination of pH sensor
Note
Cleaning and filling solutions should be handled with the same care as that given to toxic or corrosive
substances.
8.3 Disposal
Run a new calibration after treatment.
In compliance with European Directive 2002/96/EC on Waste Electrical and
Electronic Equipment (WEEE), this instrument must not be disposed of together
with domestic waste. This also applies to countries outside the EU, per their spe
cific requirements.
Please dispose of this product in accordance with local regulations at the collect
ing point specified for electrical and electronic equipment.
If you have any questions, please contact the responsible authority or the distrib
utor from which you purchased this instrument.
Should this instrument be passed on to other parties (for private or professional
use), the content of this regulation must also be related.
Thank you for your contribution to environmental protection.
Action
Degrease the membrane with cotton wool soaked
in either acetone or a soap solution.
Soak the tip of the electrode overnight in 0.1M
HCl
HCl/pepsin solution.
Remove deposits by soaking electrode in a
thiourea solution.
Maintenance
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