Advanced Instruments 3250 - Power On Diagnostics; A;D Tests

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Instrument Operation
1. At Set Buzz Amplitude, press START to display Amplitude = xxx
and activate a one-second freeze pulse.
2. Each press of the START keypad will produce an additional one-
second freeze pulse.
3. Pressing the > key will increase the setting up to a maximum of 255.
Pressing the < key will decrease the setting to a minimum of 150.
4. Press ENTER to store the new setting (or STOP to restore the
original setting).
15. Set "Buzz" Point
This menu item enables setting the temperature at which crystallization
is induced by the freeze pulse (buzz) in each range.
Most freezing point osmometers supercool all samples in the
0-2000mOsm range to approximately 3000 on the mOsm scale. The
3250 buzz points default to 3000 for the lower range and 4800 for the
upper range. Because the test results may be affected somewhat by the
amount of supercooling, these default buzz points are recommended
for general use and for the most reliable comparison of data.
Certain fluids may not freeze reliably at the default buzz point,
however, or may give more repeatable results with either more or
less supercooling than the default buzz point provides. The 3250 is
designed to accommodate these, as well as the more ordinary types of
samples.
1. At Set “Buzz” Point, press START to display the current
crystallization setting, displayed as “Buzz” Point = xxxx. To change
the crystallization point:
2. At “Buzz” Point = xxxx, the present setting must be cleared before
the buzz point can be changed. Press CLEAR to clear the setting.
Alternatively, the < > keys may be used to increase or decrease the
value, one digit at a time.
3. Enter the desired buzz point (including zeros), via the numeric key-
pad, one digit at a time from left to right. The 3250 buzz point can
be set between 2000 and 5400 on the mOsm scale in either low or
high range.