Hitachi ZA3000 Series, Instruction Manual

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11. TROUBLESHOOTING
Listed below are the possible causes and remedies of the typical
troubles that you may often encounter in the graphite furnace
analysis. If your trouble is not covered in this table, the
instrument may be faulty. In such a case, contact our service
engineer.
Symptom Possible Causes Check and Remedy
Sensitivity is low. An excess amount of carrier gas
is flowing at the atomizing stage.
Check the atomizing stage of
temperature program and adjust to an
appropriate carrier gas flow rate.
Sample bumping has occurred. Check the drying and ashing stages of
temperature program, and set an
appropriate heating temperature and
ramp/hold time.
Wavelength setting is incorrect
(wavelength deviation or
inappropriate wavelength/ slit
width/ lamp current.).
After checking Lamp Spectrum, input an
appropriate value and execute condition
setting again.
Lamp (element) is wrong. Check the lamp house and replace the
lamp with the correct one.
Sample viscosity is too high. Check the state of aspiration while
aspirating the sample and reduce its
viscosity by dilution or decomposition.
Or slow the injection speed of
autosampler.
Interference by coexisting
substance in the sample is large.
Check in comparison with the sensitivity
for standard sample. Reduce coexisting
substances’ concentration by dilution or
extraction.
Addition of a matrix modifier may be
required depending on element.
Repeatability is
poor.
Sample bumping has occurred. Check the drying and ashing stages of
temperature program, and set an
appropriate heating temperature and
ramp/hold time.
Contamination Check for contamination due to the
previous sample and clean the cuvette as
required.
Sample container is dirty. Clean the container adequately.
The graphite cuvette has been
deteriorated.
Check the firing time of graphite cuvette
and its surface roughness. Renew the
graphite cuvette when required.
Improper temperature program Check the program, and set an
appropriate heating temperature and
ramp/hold time.