Maintenance; Meter Maintenance; Electrode Maintenance; Disposal - Mettler Toledo SevenCompact S220 Instrucciones De Manejo

8 M aintenance
8.1 M eter 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
hous i ng is made of acrylonitrile butadiene styrene/polycarbonate (ABS/PC). This material is sen s i-
tive to some organic solvents, such as toluene, xylene and methyl ethyl ketone (MEK).
Any spillage should be wiped off immediately.
8.2 E lectrode 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
elec t rode 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 sen-
sor
Silver sulfide contamination of pH sensor
Note
Cleaning and filling solutions should be handled with the same care as that given to toxic or cor r o-
sive substances.
8.3 D isposal

38 Maintenance

Run a new calibration after treatment.
In compliance with European Directive 2002/96/EC on Waste Electrical
and Elec t ron i c Equipment (WEEE), this instrument must not be disposed of
togeth e r with domestic waste. This also applies to countries outside the EU,
per their specific requirements.
Please dispose of this product in accordance with local regulations at the
col l ect i ng point specified for electrical and electronic equipment.
If you have any questions, please contact the responsible authority or the
dis t rib u t or from which you purchased this instrument.
Should this instrument be passed on to other parties (for private or pro f es-
sion a l 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
Remove deposits by soaking the electrode in
an HCl/pepsin solution.
Remove deposits by soaking electrode in a
thiourea solution.