The instantaneous power consumption of an appliance is used to determine the status of the appliance, from which further actions may be taken. This invention is premised on the observation that most appliances have a characteristic power consumption pattern that can be used to determine the state of operation of the appliance. An electric coffee pot, for example, consumes high power substantially continuously during the brewing state, then reduces its power level, or power duration, or both, while keeping the pot warm, then terminates its power consumption when it is turned off. In like manner, the power consumption patterns of other appliances, such as toasters, washing machines, dryers, and so on may also be used to determine the state of each appliance. The communicated state may be used by a home-automation system to effect a variety of actions, including notifying the user, terminating the available power to the appliance, initiating an action by another appliance, and so on.
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