Merely detecting when to trigger an alarm is not very helpful - we also want to know which fault triggered the alarm
We need to add a diagnosis aspect to our detector

Thus, we desire the following characteristics of a fault detection system:

Speed

Isolability (Ability to distinguish between different failures)

Robustness

Novelty identifiability (Ability to detect previously unknown failures)

Classification error estimate

Adaptability

Explanation facility

Minimal modelling requirements

Modest storage and computational requirements

Multiple fault identifiability