Advanced Instruments 3900, User Manual

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Calibration Cassette (optional)
A specialized cassette that initiates recalibration.
Cassette Pusher (Figure 4)
Pushes each cassette in the left (input) deck into proper position for the
cassette indexing mechanism.
Cassette Index Mechanism (Figure 4)
Indexes the most rearward cassette in the left (input) deck to the right,
one position at a time, to sequentially present each sample tube to the
operating head for testing.
Insert Test Well (Figure 4)
For single, priority tests.
Sample Freezing Chamber (Figure 4)
Thermoelectric for reliability and precise control. Contains a small
amount of heat transfer fluid for optimum cooling capacity.
Heat Transfer Fluid Pre-cooling Chamber (inside)
Thermoelectrically pre-cools heat transfer fluid for faster operation.
Operating Head (Figure 4)
Contains an electrically vibrated stir/freeze wire; an ultra-stable, ultra-
precise thermistor sample probe and devices to automatically center the
thermistor in the sample. Picks up the positioned sample tube and places
it in the sample freezing chamber for testing. After the freezing point
test, the operating head returns each sample tube to its proper position
in the cassette.
Measurement and Control Circuit Boards
Provide operating mode and calibration selections on the display during
setup.
17
Instrument Operation