Operating instructions

Charged Aerosol Detectors
Corona Veo and Corona Veo RS
Operating Instructions Page 101
Problem Probable Cause Remedial Action
High baseline drift The column is contaminated. Clean or replace the column.
The system is not sufficiently
equilibrated.
Flush the system until equilibration.
The eluents are dirty or not
homogeneous.
Before you start an analysis,
homogenize eluents already in their
reservoir. Use fresh solvent and
check the eluent filter frits. In
aqueous solvents, growth of
microorganisms is possible.
The environmental conditions are
unstable.
Make sure that the temperature and
the humidity are constant. Avoid
draft.
The mobile phase is
contaminated.
Use fresh solvent. Use HPLC-grade
eluents only.
High noise, non-periodic
baseline fluctuation
There are pressure fluctuations
from the pump.
Purge the pump; check general
function (→ Pump Manual).
There are air bubbles in the
system.
Purge the system (→ Pump
Manual).
The eluent is dirty or their purity
is insufficient.
Use fresh solvent. Use HPLC-grade
eluents only.
The gas content of the eluent is
too high.
Degas the eluent.
The system is not grounded. Verify that all system components
are grounded.
The mobile phase is
contaminated.
Use fresh solvent. Use HPLC-grade
eluents only.
Connections in the system are
leaking.
Check the system for leaks and
tighten all fitting connections if
necessary.
The mobile phase is not properly
mixed.
Check the mixing function of the
pump (→ Pump Manual).
Contaminants are eluting from the
column.
Trace levels of organic compounds
may be tightly retained by the
column.
Remove the column and see if
problems persist. Clean the column.
If problems continue to exist,
replace the column (→ TCC
Manual).
The column temperature is not
held constant.
Check the thermostatted column
compartment (→ TCC Manual).