Metrohm 896 Professional Detector – Amperometry - Manual (Page 44)

6.7 Problems with the chromatogram
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2.896.0020 896 Professional Detector – Amperometry
Problem Cause Remedy
No measuring sig-
nal. IC system – No mains cur-
rent. Check mains connection and voltage.
Peaks cut off at the
top. Measuring range too
small. ￭ Set a less sensitive measuring range.
￭ Reduce peak height, e.g. by means of sam-
ple dilution.
6.7 Problems with the chromatogram
Problem Cause Remedy
Peak drift with
sugar analysis. Carbonate absorption in
the eluent. Use trap-column Metrosep CO3 Trap 1
(6.1015.300).
Peaks have poor res-
olution. IC system – Diminished
separating efficiency of the
separation column. ￭ Regenerate the separation column (see
Chapter Handling and maintenance in the
manual for the IC instrument).
￭ Replace the separation column (see Chap-
ter Handling and maintenance in the man-
ual for the IC instrument).
IC system – Eluent is old. Apply new eluent.
Ionic strength of the sam-
ple or pH of the sample
deviates greatly from the
eluent. Dilute the sample or optimize the pH of the
sample.
Absorption of analyte at
the electrodes. Use a suitable combination of electrodes and
eluent.
Unexpected change
to the retention
times in the chroma-
tograms. IC system – Diminished
separating efficiency of the
separation column. ￭ Regenerate the separation column (see
Chapter Handling and maintenance in the
manual for the IC instrument).
￭ Replace the separation column (see Chap-
ter Handling and maintenance in the man-
ual for the IC instrument).
IC system – Eluent is old. Apply new eluent.
Ionic strength of the sam-
ple or pH of the sample
deviates greatly from the
eluent. Dilute the sample or optimize the pH of the
sample.