Manual
6 Notes – Maintenance – Faults
761 SD Compact IC / Instructions for Use 8.761.1043
104
6.3 Faults and malfunctions
6.3.1 Error messages
If any type of malfunction occurs during operation of the 761 SD Com-
pact IC, this is shown by error messages in the PC program, which ap-
pear either in an error window or in the
SYSTEM STATE window.
Follow the instructions listed in the Error window and close this win-
dow with
<OK>.
You fill find further details of the error messages of the
SYSTEM STATE
window, their possible causes and the procedure for rectifying them in
the Software Instructions for Use «IC Net 2.3» Section 4.5.
6.3.2 Malfunctions and their rectification
If difficulties appear with The 761 SD Compact IC during analyses, their
causes are best investigated in The order separating column → high-
pressure pump → eluent → connections. Several of The malfunc-
tions which may appear are listed in The following table with details of
possible causes and countermeasures.
Malfunction Cause Rectification
Baseline with high
noise level, pulsa-
tion
• Contaminated pump
valves
• Defective piston seals
• Clean the valves (see Sec-
tion 6.2.5)
• Replace the piston seals
(see Section 6.2.5)
Drift of the
baseline
• Thermal equilibrium not
yet reached
• Leakage in the system
• Condition system with
heating switched on
• Check connections and
seal them
Considerable
pressure drop
• Leakage in the system • Check connections and
seal them
Considerable
pressure rise
• Blockage of filter unit
PEEK 6.2821.120
• Change of column pack-
ing by injection of con-
taminated samples
• Replace the filter
6.2821.130 (see Section
2.3.3)
• Regenerate the column or
replace the column (see
Section 6.2.4)
Note
:
Samples should always
be microfiltered
Chromatograms
with poor resolu-
tion, Change in
the retention times
• Deterioration in separa-
tion efficiency of the IC
column
• Regenerate the column or
replace the column (see
Section 6.2.4)
Extreme peak
broadening,
splitting (double
peaks)
• Dead volume at the col-
umn ends
• Regenerate the column
(see Section 6.2.4)