Calibrating the Baseline (T1 Heat Flow)Calibrating the Baseline (T1 Heat Flow)
The baseline slope and offset calibration involves heating an empty cell through the entire temperature range expected in subsequent experiments. The calibration program is used to calculate the slope and offset values needed to flatten the baseline and zero the heat flow signal. This calibration is used in the DSC Q10 and when the selected heat flow is T1 for the DSC Q100 or Q1000.
Baseline Slope is a calibration constant that accounts for the baseline slope of an empty cell. The baseline slope is calculated from data gathered as an empty cell is heated through the temperature range expected in subsequent experiments. Default is 0.00.
Baseline Offset is a calibration factor that shifts the curve up or down along the Y-axis to balance the heat flow at the sample and reference thermocouple positions. The baseline offset is calculated from data gathered as an empty cell is heated through the temperature range expected in subsequent experiments.
Select from the following topics for more information:
Gathering Baseline Calibration Data: There are two ways to gather the calibration data, either manually by using the Baseline template or by using the Calibration Wizard. For information on each method click on the desired topic listed below.
Baseline calibration involves heating an empty cell through the entire temperature range expected in subsequent experiments. The calibration program is used to calculate the slope and offset values needed to flatten the baseline and zero the heat flow signal.
This calibration experiment may be performed by setting up the experiment manually using the Experiment View or automatically using the calibration wizard.
A general procedure for baseline calibration is given below:
Remove any pans from the cell and cover the cell.
Check that your purge gas is connected and set to the desired flow rate. If you are using an RCS or LNCS, be sure a Base purge gas is also used.
Select Experiment View and access the Summary Page, then set the instrument to Calibration mode using the Mode drop-down list.
Select the "Baseline" test from the Test list.
Select "Baseline" from the Sample Name list. Enter the requested sample information, including zero as the Sample Size.
Click on the Procedure tab. Enter the requested test parameters that will heat the DSC cell over the same temperature range, at the same heating rate that will be used for subsequent experiments.
Click on the Notes tab. Enter/verify the requested information. If an MFC is installed, set the desired flow rate.
Click on the Apply button to save the experimental and sample parameters entered for this run.
If more than one run is in the sequence list, schedule this run. (An arrow will appear next to the run number in the Sequence Pane for the scheduled run.)
Select Start to begin the calibration run.
Wait until the run is complete, then access the calibration program using Calibrate/Analysis on the DSC menu.
Analyze the data. See Analyzing DSC Calibration Data.
Save the calibration results by clicking the Accept button (or by selecting Analyze/Accept results from the Calibration menu). This will update the current temperature parameters with this calibration data.
You can verify this result by viewing the Cell Calibration Table (selected from the Calibrate menu).
For basic calibration information see: Calibrating the DSC.
The window displayed after selecting the Calibration Wizard will depend upon your specific DSC Q Series instrument model. Follow the steps below for the DSC model desired:
Q10 Calibration Wizard
Follow the steps below when using the calibration wizard with a DSC Q10:
Verify that the installed cooler type is selected on the Tools/Instrument Preferences/Cooler Page.
Select Calibration Wizard from the Calibrate menu.
Select the
Baseline option
and follow the steps displayed. For information on the next step click
here 
more.
Q100/Q1000 Calibration Wizard (Heat Flow T1)
Follow the steps below when using the calibration wizard with a DSC Q100 or Q1000:
Select Calibration Wizard from the Calibrate menu.
Verify/select the installed cooling device and desired heat flow signal. Based on the heat flow selection the appropriate wizard will be displayed.
Select the
Baseline option
and follow the steps displayed. For information on the next step click
here more.