PerkinElmer aanalyst 200, User Manual

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AAnalyst 200 User’s Guide
10-13
Troubleshooting Deuterium Background Corrector
Problems
Background correction requires the use of both the primary and the continuum source. It is
important that these sources be of similar intensity and pass through exactly the same area of the
sample cell. There are three possible problems that may be observed when the background
corrector source lamp is not aligned or needs replacing:
•
Measurements are excessively noisy.
•
The intensity of the background source may be much less than the intensity of the primary
source.
•
Background absorbance may not be properly corrected. You can check this by measuring a
sample containing only matrix components with no analyte.
These problems indicate that the background corrector source is either not properly aligned or
should be replaced. Refer to the section called
Replacing the Deuterium Lamp in Maintenance
chapter if it needs replacing.
Possible Cause of Problem Check and/or Remedy
Background source
intensity is much
lower than the
primary source May not need to use the
background corrector. Determine if the background corrector
should be used. It is useful up to about
400 nm.
The intensity is not matched. 1). Reduce the hollow cathode or the
EDL current in order to reduce the
primary source intensity. This may
increase the noise for the
determination.
2). In addition (or alternatively)
increase the slit width (this may
increase the possibility of spectral
interferences or increase the
calibration curvature).
The deuterium lamp may need
replacing (B315-0160). Replace the lamp.