Routine Maintenance: Detectors
Maintaining a Microcell Electron Capture Detector (µECD)
Released: March 2004 6850 Series II GC User Information page 201 of 256
Correcting performance problems
Performance problems, such as an output reading that is too high or too low or
unsatisfactory chromatographic results (for example, a noisy baseline), can be
caused by leaks or deposits in the detector or other part of the
chromatographic system. To determine the location of the problem, you need
to perform a series of tests.
Before testing the detector, consider the nature of the problem. If you have
recently made a change to the GC system and now see an elevated output level,
there is a good chance that the change has either introduced contaminants or
caused a leak in the system. For example, if you recently switched gas supplies,
the new gas may contain impurities. Or if you recently installed a new column,
there could be a leak at the detector fitting.
If the output value or noise level has been increasing gradually, the cause is
probably a slow build-up of deposits. The detector may contain contaminants
from column bleed or a trap may be saturated. If the change has been gradual
and if you have not modified the GC system recently, you can probably start by
checking for contamination. Note: Contamination in this procedure refers to non-
radioactive deposits from such things as column bleed or dirty samples!
To Next Page
Loading...
Need help?
General
