TA Instruments DSC Q Series, Руководство по началу работы

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DSC Q Series Getting Started Guide
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for subsequent samples. The heating rate can be set to a nominal value of 5 °C/min or the calibration experiment
can be performed isothermally if you are calibrating just the Reversing Heat Capacity.
At the end of the experiment the calibration constants for the Total and Reversing Heat Capacity signals are
manually calculated by dividing the theoretical value of heat capacity, at the desired temperature, by the
measured value. The constants are then manually entered into the instrument control software, where they are
automatically applied to future experiments. See the online help for more detailed information.
Pressure Calibration
Pressure calibration is an optional calibration procedure for the Pressure DSC cells. It is based on comparing
the pressure reading at two points, typically one atmosphere and another pressure selected by you, to the pressure
reading on an external pressure gauge.
Autosampler Calibration
The DSC Autosampler may require recalibration to refine pan placement and pickup capabilities. Autosampler
calibration involves calibrating both the cell and tray positions. These procedures have been automated for ease-
of-use operation. You can choose to calibrate both the sample tray and cell areas by using the calibration functions
from the touch screen or from the instrument control program.
Once the Autosampler is correctly calibrated, you may need to recalibrate it only when you replace the DSC
cell. Periodic checks are the best way of determining when the Autosampler needs recalibration. For more
complete information on calibrating the Autosampler, see the online documentation.
Q2000/Q200/Auto Q20 Autosampler Calibration
To perform Autosampler calibration follow these steps:
1. Access the Autosampler calibration functions via the touch screen or the instrument control menu. Refer
to the section that applies.
• Autosampler Calibration via the Touch Screen
a. Touch the Calibrate button at the bottom
of the touch screen. The screen shown in
the figure to the right will be displayed.
b. Press the Autosampler button.
c. Touch the Calibration tab, if it is not
already selected. The screen shown on
the next page is displayed.