TA Instruments TMA 2940 CE, Руководство оператора

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TA I
NSTRUMENTS
TMA 2940 CE 3–19
• Because of its conductivity, helium is the
purge gas recommended for performing
TMA measurements at temperatures below
ambient. Helium reduces the time required
to cool the sample, provides a more stable
sample environment, and reduces cold drafts
on the system mechanism.
• Use the following helium purge rates for
subambient operation:
100 mL/min at –100 o C and above
200 mL/min at –150
o
C and above.
• If a denser purge gas than helium is used for
subambient experiments, it is recommended
that the silicon washer found in the
accessory kit be attached to the probe.
Raise the probe to the fully open position,
then place the washer so it is just below the
opening in the stage. This will minimize cold
drafts into the lower balance enclosure.
• Let the purge gas flow for 3 to 5 minutes
before adding coolant or starting the run;
doing so allows a thorough exchange of
sample atmosphere.
Starting an
Experiment
You can begin the experiment using either the
START
key on the TMA keypad or Start on the
controller.
Running a TMA Experiment