摘要 |
A device is provided for monitoring a plurality of appliances, wherein each appliance is connected to an electrical circuit having a first wire and a second wire. The device includes a plurality of cores, each of the plurality of cores being constructed to be able to surround one of the first wires of each circuit and having a secondary winding at which an electrical signal is generated in response to a current polarity change in the first wire. A multiplexer is connected to the secondary winding of each of the plurality of cores. A processor is connected to the multiplexer to monitor the phase relationship between an AC voltage an AC current of each appliance connected to one of the plurality of circuits and to determine information relating to the function of the appliance based on the phase relationship. The device may be located at the circuit breaker box of an establishment.
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