Method and device for detecting drifts, jumps and/or outliers of measurement values

An apparatus for detecting an alarm state in a signal while avoiding false alarms from gradual signal drifts and outlier measurements, comprising:

• means for obtaining a measurement value of the signal at a current time;
• a processor for determining a position parameter and a deviation parameter from previous measurement values of the signal that were measured during a time window, wherein the time window is offset in time by the processor by an adjustable time delay from the current time, the processor computing at least one of an evaluation quantity, an alarm threshold, and an outlier threshold based on the measurement value, the position parameter, and the deviation parameter, wherein the processor determines that a measurement value is an outlier measurement if the evaluation quantity exceeds the outlier threshold;
• and
• means for indicating an alarm state in response to the processor determining that the evaluation quantity exceeds the alarm threshold but not the outlier threshold, whereby the alarm state indicates a significant drift or jump of the signal.

An article of manufacture comprising a computer program carrier readable by a computer and embodying one or more instructions executable by the computer to detect an alarm state in a signal while avoiding false alarms from gradual signal drifts and outlier measurements, the computer program comprising:

• program instructions for obtaining a measurement value of the signal at a current time;
• program instructions for determining a position parameter and a deviation parameter from previous measurement values of the signal that were measured during a time window, wherein the time window is offset in time by an adjustable time delay from the current time;
• program instructions for computing at least one of an evaluation quantity, an alarm threshold, and an outlier threshold based on the measurement value, the position parameter, and the deviation parameter;
• and
• program instructions for indicating an alarm state in response to the evaluation quantity exceeding the alarm threshold but not the outlier threshold, wherein the measurement value is determined to be an outlier measurement if the evaluation quantity exceeds the outlier threshold, whereby the alarm state indicates a significant drift or jump of the signal.