Metrohm 896 Professional Detector – Amperometry - Manual (Page 45)

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6 Troubleshooting
2.896.0020 896 Professional Detector – Amperometry
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Problem Cause Remedy
Extreme spread of
the peaks in the
chromatogram.
Splitting (dual
peaks) IC system – Dead volume
at the ends of the separa-
tion column. Replace separation column.
IC system – Dead volume
in the IC system. Check the capillary connectors.
Inhibition of the detection
mechanism by the analyte
(with PAD). ￭ Dilute the sample.
￭ Allow the waveform to run-in better.
￭ Adjust the PAD waveform.
Overload the column. Dilute the sample.
6.8 Other problems
Problem Cause Remedy
High background
current. IC system – Eluent conta-
minated. Apply new eluent.
Software – Measurement
potential / pulse settings
incorrect. Optimize parameters.
Very wide peaks through
substances with delayed
elution. Wait for the complete elution of these sub-
stances.
Unstable tempera-
ture. The set temperature is too
low. Set the temperature to at least 8 °C higher
than the highest ambient temperature to be
anticipated.
Current display/
charge display in the
software is frozen. Measuring cell – electrodes
are either not connected or
not correctly connected. Connect the electrode connection cables cor-
rectly (see Chapter 4.7, page 25).
Measuring cell – Small air
bubbles in the measuring
cell. Deaerate the measuring cell (see Chapter 4.6,
page 24).
Measuring cell – Electrode
connection cable defective. Perform instrument test with dummy cell (see
Chapter 4.1, page 17).