MODEL 1000
5.5.4.3
Baseline Drift
To ensure that the baseline is not drifting, compare the baseline upsets caused by valve actuations
with those of the chromatogram provided with the Operational Parameters Sheet. Ensure that no
evidence of component elutions is present when no sample is being injected.
If differences exist between the two chromatograms, the problem may be due to one or more of the
following:
1.
Programming of events
2.
Contamination of valve sealing diaphragms by foreign matter
3.
Improperly adjusted flows
4.
Leaks in the carrier system
5.
Column deterioration due to liquid contamination from a sample
6.
Misidentifying peaks
A noisy baseline can be caused by carrier leaks, an electronic failure in the Preamplifier, a faulty
power supply, or defective thermistors in the detector. If the baseline is still noisy after correcting
for leaks, perform the Detector Bridge Balance procedure before replacing the detector thermistors
or the preamplifier board.
MAINTENANCE
SEP 2005
5-15