Metrohm 850 Professional IC AnCat Nonsuppressed - Manual (Page 94)

6.1 Problems and their solutions
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84 ￭￭￭￭￭￭￭￭
850 Professional IC–AnCat – non-suppressed
Problem Cause Remedy
￭ Replace separation column (see "Connect-
ing and rinsing the separation column",
page 56).
Conductivity detec-
tor is not recognized
in the software No connection.
￭ Check the cable connection (28- 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 3.5, page
17) (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 3.18,
page 53).
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 56).
Precision problems -
significant scatter-
ing of the measured
values Sample – Gas bubbles in
the sample. Use sample degasser (see Chapter 3.13, page
43).
Injection valve – sample
loop. Check installation of the sample loop (see
Chapter 3.14.1, page 44).
Sample – Rinsing volume
too low. Prolong the rinsing time (see Chapter 5.8,
page 76).
Injection valve – defective. Request Metrohm Service.
Unexpected change
to the retention
times in the chroma-
tograms Separation column –
diminished separating effi-
ciency. ￭ Regenerate separation column (see Chap-
ter 5.12.4, page 80).
￭ Replace separation column (see "Connect-
ing and rinsing the separation column",
page 56).
Eluent – Gas bubbles in the
eluent. Check connections of the eluent degasser (see
Chapter 3.9, page 34).
High pressure pump –
defective. Request Metrohm Service.