Advanced Instruments 4C3, User Manual

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2. Gently wipe the mandrel, probe and stir/freeze wire (see figure
8 on next page) with a pure water dampened tissue to remove
any contaminants 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
Lactrol
®
530 is recommended for milk). Swirl and carefully
open an ampule of the reference solution (or NaCl standard)
selected.
4. Select two clean sample tubes. Pipet or measure identical sam-
ples of the selected reference solution or NaCl standard into the
clean sample 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 solution or NaCl standards into
identical sample 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 section G. When checking calibration and repeatability with
34
The Advanced
®
Model 4C3 User’s Guide
Figure 8: Operating Head