Metrohm 2.946.0010, Руководство пользователя

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7.3 Application problems
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Problem Cause Remedy
suring range the maximum current which is
displayed correctly is ±4 µA. Please note that in
square-wave and differential pulse measuring
mode only potential differences are displayed,
so the absolute measured current can be
higher than what is displayed.
Select the next higher current measuring range
or consider using current measuring range
Auto , and repeat the determination. Please
note that with
Potential step / Sweep rate < 20 ms or
Potential step
·
Frequency < 20 ms the use
of a fixed current range is recommended.
Gas bubbles stick to one of
the electrodes. Remove the gas bubbles and check the
method parameters to prevent the formation
of more gas bubbles.
Curve shape - the
curves are very
noisy. The electrode is not in a
good condition. Clean the electrode as recommended in the
application documentation and repeat the
determination. If the situation does not
improve, replace the electrode by a new one.
Moisture penetrated the
SPE holder.
Remove the SPE from the holder and thor-
oughly dry the electrical connection for the
SPE.
The conductivity of the
measuring solution is too
low. Verify the concentration of the electrolyte solu-
tion and the volume of electrolyte added for
the application. In case of doubts prepare a
fresh electrolyte and repeat the determination.
The electrolyte is too old. Prepare a fresh electrolyte solution. Also con-
sider the stability and age of the reagents used
for the preparation.
The current measuring
range is too high. The resolution of the current measurement is
0.25% of the selected current measuring
range. This means the higher the selected cur-
rent measuring range the poorer the current
resolution.
Select the next lower current measuring range
or consider using current measuring range
Auto
, and repeat the determination. Please