PerkinElmer PINAACLE 900 Series, Руководство по оборудованию и обслуживанию для клиентов

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Maintenance
5. If you have installed a new graphite tube, perform the procedure outlined in
Conditioning the graphite tube on page 305.
If you are reusing a previously conditioned graphite tube, heat manually at
2500 °C for 5 seconds to remove surface contamination.
6. Every time you open the furnace, subsequently always heat it out manually at
2500 °C for approximately 5 seconds.
7. Check alignment of the furnace (see Aligning the Graphite Furnace on page
186).
8. Check alignment of the furnace autosampler (see To Align the Autosampler
Tip in the Graphite Tube on page 145).
Cleaning the graphite tube and graphite contacts
Good, reproducible analytical results depend on good electrical contact between
the graphite contacts and the graphite tube. The contact surfaces of the graphite
tube and the graphite contacts must be smooth and clean to allow good electrical
contact.
After prolonged use the graphite contacts may become contaminated with
remnants of samples and small particles of graphite. Even quite small particles
can spoil the contact and cause poor analytical results.
Every time that you open the furnace, clean the contacts as described in
Cleaning the contact surfaces of the graphite tube and contacts on page 301.
Note
Do not touch the graphite tube or contacts with your fingers. Perspiration
can affect the tube lifetime and the analytical results by contaminating and
damaging the surface of the graphite.
If a graphite tube breaks inside the furnace you must remove all the
remnants and thoroughly clean the contacts.