Advanced Instruments 4C3, Руководство пользователя

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When setting the base value, be doubly sure of your num-
ber, scale, and mathematics. For example, as indicated in the
Foreword, the average freezing point of cows milk in the U.S.A.
has been found to be around -540 m°H, which converts to -522
m°C. If ” 522 ” is used when the “Set % DFB” requires Celsius,
the current -525 m°H AOAC confirmation level should indicate
“3% DFB” (3% difference from base). However, if ” 540 ” is
used by mistake, a false indication of 6% will be obtained.
b. When the base is set as required, press ENTER to save the set-
ting and return the display to “Set % DFB” .
Note that pressing stop at that point, instead of enter, would
have canceled the new setting and restored the previous setting.
At “Set % DFB” , you may want to repeat the setting sequence
to make sure the desired base reading has actually been record-
ed.
c. At “Set % DFB” , press stop to return the display to
“Cryoscope Ready” .
When any non-zero base is set, every sample test result will
be displayed with a % DFB value. When the base is set to 0,
no % DFB will be displayed. Thus, if you wish to eliminate
the % DFB display, simply press the clear button at “Base
Reading = xxx mC” (or xxx mH ) or set the base value to 0,
then sequentially press enter and stop to return the display to
“Cryoscope Ready” .
13. Select Display mH/mC
This menu item enables changing the readout temperature units (see
the Foreword for a discussion of the units of measurement used for
milk cryoscopy).
CAUTION Changing this setting requires changing the % DFB
setting (if not set at zero), as well. (See Set % DFB .)
28
The Advanced
®
Model 4C3 User’s Guide