Metrohm 850 Professional IC Anion MCS LP-Gradient - Manual (Page 121)

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6 Troubleshooting
850 Professional IC – Anion – MCS – LP Gradient
￭￭￭￭￭￭￭￭ 111
Problem Cause Remedy
￭ Replace separation column (see "Connect-
ing and rinsing the separation column",
page 73).
Conductivity detec-
tor is not recognized
in the software No connection.
￭ Check the cable connection (38- 1 ).
￭ Turn the instrument off and on again (after
15 seconds).
Extreme spread of
the peaks in the
chromatogram.
Splitting (dual
peaks) Connections – dead vol-
ume in the system. Check the connections (see Chapter 3.6, page
20) (use PEEK capillaries with an internal diam-
eter of 0.25 mm between the injection valve
and detector).
Guard column – diminished
performance. ￭ Replace guard column (see Chapter 3.23,
page 70).
Separation column – dead
volume at column head. ￭ Install separation column in reverse flow
direction (if permitted by the information
sheet).
￭ Replace separation column (see "Connect-
ing and rinsing the separation column",
page 73).
Greater rise in the
baseline MSM – reduced capacity. Regenerate the MSM (see Chapter 5.11.3.1,
page 96).
Precision problems -
significant scatter-
ing of the measured
values Sample – Gas bubbles in
the sample. Use sample degasser (see Chapter 3.15, page
48).
Injection valve – sample
loop. Check installation of the sample loop (see
Chapter 3.16.1, page 50).
Sample – Rinsing volume
too low. Prolong the rinsing time (see Chapter 5.8,
page 93).
Injection valve – defective. Request Metrohm Service.
MCS – vacuum too low. ￭ Check connectors. If they are ok:
￭ Contact the Metrohm Service.
Unexpected change
to the retention
times in the chroma-
tograms Separation column –
diminished separating effi-
ciency. ￭ Regenerate separation column (see Chap-
ter 5.15.4, page 106).
￭ Replace separation column (see "Connect-
ing and rinsing the separation column",
page 73).