Advanced Instruments 3900, User Manual

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selection feature in Installation & Setup to make this selection. Failure
to select the right material may affect instrument performance.
If either batch numbering or bar code scanning has been enabled, follow
the procedure in Installation & Setup before re turning to the following
steps. If neither batch num bering nor bar code scanning has been
enabled via the setup menu, instrument operation in the following man-
ner is recommended:
1. Check the probe wipers (see figure 4). Replace the wiper sponges
when they begin to appear dirty or about every 50 tests.
Check the drip catcher (see figure 4). Replace the drip catcher
sponge when it appears dirty, ineffec tive or shows excessive wear.
2. Gently wipe the mandrel, probe and stir/freeze wire (see figure 7)
with a pure water dampened tis sue to remove any contaminant from
prior tests; re-wipe after about every 50 tests. Be careful not to bend
the probe or stir/freeze wire.
3. Select a reference solution or NaCl standard with a freezing point
close to that expected for your unknown (Advanced Clinitrol™ 290
is recom mend ed for serum). Swirl and carefully open an ampule of
the reference solution (or NaCl standard) selected.
4. Select two clean sample tubes. Pipet or measure identical samples of
the selected reference solution or NaCl standard into the clean sam-
ple tubes and place the tubes in the first two positions of the first
cassette.
5. Depending upon your required protocol, pipet or measure additional
samples of reference so lution or NaCl standards into identical sam-
ple tubes and load them into the next positions in the cassette to
check repeatability and accuracy before running tests on unknown
samples. Follow the techniques recommended in step 6. When
checking cal ibration and repeatability with standards or refer ence
solutions, it is usually best to average the readings from three to five
aliquots of each sample to avoid error.
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Instrument Operation