TA Instruments TMA 2940, Operator'S Manual

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Using Your Options
TA I
NSTRUMENTS
TMA 2940 4–24
4. Hold the probe-locking lever in the up
position and continue lowering the probe
into the stage until you can feel it seat in the
locking mechanism.
5. Tighten the probe-locking lever by turning it
clockwise.
6. Position the sample thermocouple on the
stage so that the tip is 13 mm (0.5 inch)
above the stage.
7. Change the instrument mode, if needed.
Calibration
In addition to the normal probe calibration, the
dilatometer accessory should be calibrated for
baseline and displacement using the procedures
described as follows.
Baseline
Calibration
The dilatometer filling medium must be kept dry.
Store it in a desiccator when it is not being used.
If the sample has become contaminated through
long exposure to humidity, dry it in a vacuum oven
at 200
o C for one hour.
Run a thermal scan, under the same load that
will be used when analyzing your samples
(typically 0.01 N or less). Use a vial three-
quarters full with filling medium only (no
sample). Make sure the filling medium is well
packed.
Marking the vial at the fill level and filling future sample
runs to this level will insure that the baseline effect due
to the fill medium are minimized from run to run.
NOTE:
NOTE: