Owner manual

5 Notes – Maintenance – Faults
761 Compact IC
186
5.3 Faults and malfunctions
5.3.1 Error messages
If any type of malfunction occurs during operation of the 761 Compact
IC, this is shown by error messages in the PC program, which appear
either in an error window or in the
SYSTEM STATE window.
Follow the instructions given in the error window and close this win-
dow with
<OK>.
You will find further details of the error messages of the
SYSTEM STATE
window, their possible causes and the procedure for their rectification in
section 4.3.8.
5.3.2 Malfunctions and their rectification
If difficulties appear with the 761 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,
pulsation
• Contaminated pump
valves
• Faulty piston seals
• Clean the valves (see
section 5.1.5)
• Replace the piston seals
(see section 5.1.5)
Drift of the
baseline
• Thermal equilibrium not
yet reached
• Leak in system
• Evaporation of organic
solvent in eluent
• Condition system with
heating switched on
• Check connections and
make leakproof
• Ensure better closure of
eluent supply vessel
Considerable
pressure drop
• Leak in system • Check connections and
make leakproof
Considerable
pressure rise
• Contamination of the
filter in the 6.2821.120
Filter unit PEEK
• Contamination of the
column inlet filter
• Change of column
packing by injection of
contaminated samples
• Replace the 6.2821.130
Filter (see section 2.3.6)
• Clean or replace
6.2821.020 Steel mesh(es)
• Regenerate column (see
section 5.1.1) or replace
column
Note:
Samples should always
be microfiltered.