Why is the pressure signal from an ML283 Human NIBP Controller drifting with the Auto Calibration feature turned off?

The ML283 Human NIBP Controller's Auto Calibration feature (accessible in the Human NIBP Controller's settings window in LabChart) adjusts the pressure signal to follow any changes in finger physiology during data collection and should normally be enabled.

servlet.ImageServer?id=015w0000002NjZi&oid=00D20000000HncM


If it becomes necessary to turn the feature off at specific point during an experiment, it is advised not to measure longer than 5 to 10 minutes with the Auto Calibration feature switched off as some pressure drift may result.