Waters GCT Premier Operator's Manual page 123

3. Double-click at the top of the Spectrum window.
4. In the Header Editor, click Spectrum QTOF in the Group list.
5. Click Temp Correction in the Element list.
6. Click OK.
Result: The current temperature inside the instrument is displayed in
Spectrum window.
7. Repeat the same acquisition later in the day under the same conditions
and when the room temperature has changed by up to 3°C.
8. Display both spectra.
9. From the difference in mass and the difference in temperature, the drift
constant can be calculated in ppm/°C.
Note: The instrument applies the temperature compensation only when
the acquisition is performed using a calibration file.
See also:
Dynamic External Calibration Temperature Compensation on page 5-16
10. Open the TDC Settings window.
11. Click Use DXC Temperature Compensation.
12. Specify the value you calculated in the Drift (PPM/C) field.
13. MassLynx records the temperature at which it was calibrated, and then
applies the ppm/degree value according to the measured temperature on
each spectrum.
Requirements:
can be generally achieved for less than 3°C temperature drift. If more
reliable mass accuracy is required or the instrument is subject to a
temperature variation of greater than 3°C, then you have to use a lock
mass.
Using DXC, a mass accuracy of less than 10 ppm RMS
Dynamic External Calibration Temperature Compensation 5-17