Thermo Scientific Dionex UltiMate 3000 Series Operating Instructions Manual page 176

UltiMate 3000 Series:
NCS-3500RS and NCP-3200RS
Problem
Poor peak area precision
Page 168
Probable Cause
The capillary connections are not
installed properly or they are
leaking.
There are dead volumes in the
capillary connections.
There are air bubbles in the pump
heads and/or flow meter.
After changing solvents, the
previous solvent has not been
flushed out completely.
The gradient is irreproducible.
The sample is unstable and
decomposes.
Baseline fluctuations
The environmental conditions are
unstable.
Contamination occurs
somewhere in the system.
For additional causes, see the
Autosampler manual.
If the problem is observed while
the module is used together with
a mass spectrometer, the nanoESI
emitter may be the cause.
Remedial Action
Check and tighten the
capillary connections.
Consider using Viper
capillaries.
Replace the conventional
(non-Viper) fitting
connections. Make sure that
the capillaries are connected
correctly. Consider using
Viper capillaries.
Purge the pump (→ page 72).
Purge the pump (→ page 72).
The pressure transducer offset
may not be correct. Check the
offset and calibrate the
pressure transducers if
required (→ page 172).
Use new sample or change
the conditions. Cool the
sample in the autosampler if
possible.
See the remedial actions
provided in the related
baseline sections further up in
this table.
Make sure that the
temperature and the humidity
are constant. Avoid draft.
Consider using the
thermostatted column
compartment.
Flush the system with an
appropriate solvent.
→ Autosampler manual
→ Instrument manual
Operating Instructions