TA Instruments TMA 2940 CE, Руководство оператора

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Running Experiments
TA I
NSTRUMENTS
TMA 2940 CE 3–6
• When you change software
• Periodically (approximately once a month).
A force calibration performs the functions of a
probe calibration (see the next section). There-
fore, it is not necessary to perform a probe
calibration immediately following a force
calibration.
Probe Calibration
This procedure, sometimes called “initializing,” is
used to calibrate zero force, the LVDT, and the
probe's compliance. It corrects for any differ-
ence in the different probes used on the TMA
2940 CE and should be done every time you
change the instrument mode or when you change
a probe on the TMA 2940 CE. This calibration is
performed from the TA controller.
Temperature Calibration
Temperature calibration is based on a run in
which a temperature standard ( e.g. , indium) is
heated through its melting point. The recorded
melting point of this standard is compared to the
known melting point, and the difference is
calculated for temperature calibration.
In addition, you can use up to four other stan-
dards to calibrate temperature. If you use one
pair of known and observed points, the entire
curve is offset, or shifted, to the actual melting
point. If you use multiple standards, the tempera-
ture is corrected by a cubic spline fit. The
multiple-point temperature calibration is more
accurate than the one-point calibration.
NOTE: