The column may be inserted too far into the flame of an FID, NPD or FPD detector Replace column.Ĭlean or replace flow or pressure regulator(s). It may be due to impurities in the carrier gas or to excessive temperatures. If the detector signal does not drop in 10 minutes, immediately cool the column and check for leaks.Īllow sufficient time for temperature equilibration of the detector.ĭownward drift is frequently due to the "back-out" of contaminants from the detector or other parts of the GCĭamage to the stationary phase of the GC columnĭetermine the cause of the damage. Maintain the temperature until flat baseline is observed. Increase the oven temperature to close to the maximum continuous operating temperature for the column.
Spiking is presented by peaks with no width, either positive or negativeĭownward drift for a few minutes is normal after installing a new column.Offset is sudden unexplained change of the baseline position.Noise is rapid and random movement of the baseline position.Drift means slow baseline movement in one direction.Baseline problemsīaseline problems could be divided into 5 categories: drift, noise, offset, spiking and wander. Regular preventive maintenance depends on particular model of GC and you should consult required operations in the operator's and service manuals.įor the problem identification we recommend to use electronic flowmeter and leak detector. For example, replacing septa or liner at regular intervals and keeping the injector and detector clean and well-maintained shoud solve many problems.
Many GC problems can be prevented if the column is properly installed and GC is maintained routinely. » Chromatography » Hints and tips » GC troubleshooting » GC troubleshooting GC troubleshooting Prevention
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