Metrohm 940 Professional IC Vario TWO, Руководство пользователя

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6.1
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940 Professional IC Vario TWO (2.940.2100)
Problem Cause Remedy
Individual peaks are
greater than expec-
ted. Sample – Sample carry-
over from previous meas-
urements. Check the rinsing time (see "Checking the rins-
ing time", page 69) .
The background
conductivity is too
high. The incorrect eluent is
being used. Change the eluent (see Chapter 5.5.2, page
50) .
The retention times
are poorly reprodu-
cible. The eluent path has a leak. Check all of the connections along the eluent
path and fix the leak.
The eluent path is blocked. Check the eluent path and eliminate the block-
age.
The eluent contains gas
bubbles.
￭
Check the connectors of the eluent degas-
ser .
￭
Deaerate the high-pressure pump (see
Chapter 3.18, page 35) .
Chromatograms
have poor resolution Separation column –
Diminished separating effi-
ciency.
￭
Regenerate the separation column (see
Chapter 5.14.4, page 70) .
￭
Replace the separation column (see "Con-
necting the separation column", page 41) .
Extreme spread of
the peaks in the
chromatogram.
Splitting (dual
peaks) Capillary connections –
Dead volume in the sys-
tem. Check the capillary connections (see Chapter
3.2, page 14) (use PEEK capillaries with an
inner diameter of 0.25 mm between the injec-
tion valve and detector).
Guard column – Dimin-
ished efficiency. Replace the guard column (see Chapter 3.19,
page 37) .
Separation column – Dead
volume at the column
head.
￭
Install the separation column in the oppo-
site flow direction (if the leaflet says this is
permissible) and rinse into a beaker.
￭
Replace the separation column (see "Con-
necting the separation column", page 41) .
Precision problems -
the measured values
are highly scattered.
Injection valve – Sample
loop. Check the installation of the sample loop (see
"Optional: Exchanging the sample loop",
page 29)
.
Sample – There are gas
bubbles in the sample. Use the sample degasser .
Sample – The rinsing vol-
ume is too small. Increase the rinsing time (see Chapter 5.13,
page 68) .