Alerting policy

Vibration-anomaly alert threshold (z-score): 2.5

This case study monitors one machine's vibration sensor over 200 days using a simple rolling z-score anomaly detector. A lower z-score threshold flags more readings as anomalous, catching the buildup to a real failure earlier, but also triggers more false alarms from ordinary sensor noise.

200-day outcome

Alerts raised—

Failures caught in advance—

False alarms—

Vibration reading over time (dashed = alert threshold, red = true failure onset)