Astronomy:Non intrusive appliance monitoring
Non Intrusive Appliance Monitoring is a method to determine from a centralized point (e.g. a fuse board or distribution point) what appliances are being powered on and off in a building without the need to have individual sensors on individual loads.
Methods
Two main methods are proposed for detection of an appliance switching on or off.
Steady state detection
Steady state detection - where the final state of the power etc. is measured or transient - where the start up or change in level is identified.
Reactive power
In order to differentiate between 2 appliances with very similar loads other parameters, e.g. Reactive power, can be used to differentiate between them.
Other methods
Investigation is continuing into whether there are any other distinguishing parameters to identify similar appliances (including the frequency domain).
See also