OHAUS a-AB33EC, Инструкция по эксплуатации

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EN-38 Analyzer and Bench Meter
11.2 Meter maintenance
Never unscrew the two halves of the housing!
The meter does not require any maintenance other than occasional wipe with a damp
cloth and the replacement of depleted batteries.
The housing is made of acrylonitrile butadiene styrene (ABS). This material does not
hold up well to some organic solvents such as toluene, xylene and methyl ethyl ketone
(MEK). Any spillage should be immediately wiped off.
11.3 Electrode maintenance
11.3.1 PH electrode maintenance
Make sure the electrode is filled with electrolyte solution. Always store the electrode
according to the electrode instruction manuals and do not allow it to dry out. It is
necessary to store a pH electrode in a solution in order to keep the glass membrane of
the pH electrode hydrated. Ideally a storage solution should be used. Never store an
electrode in distilled or deionized water.
If the electrode response becomes sluggish or the slope is not acceptable, try the
following:
 Soak the electrode in 0.1M HCl for at least 8 hours.

For fat or oil contaminant, degrease the membrane with cotton wool soaked in
either acetone or a soap solution.
After electrode treatment, a new calibration should be performed. If the electrode slope
is still not acceptable, the electrode might need to be replaced.
11.3.2 Conductivity electrode maintenance
Conductivity Cell Storage
Conductivity cells can be stored in distilled or deionized water between measurements.
For overnight storage or long-term storage, conductivity cells should be thoroughly
rinsed and stored dry.
Conductivity Probe Maintenance
Cleaning recommendations:
Table 11-3 Cleaning
Contaminant Cleaning Solution Cleaning Time
Water soluble contaminants Rinse with deionized water No limit
Lubricants and oils Soak in warm water about 60°C
and liquid detergent
10 to 30 minutes
Lime or hydroxide coating Soak in 10% acetic acid or 10%
hydrochloric acid
10 to 30 minutes