US Patent 7268294 Adaptor; controller and plug receptacle for electronic device

In a system which includes adaptors a controller and plug receptacles connected to electronic devices, an adaptor that can store identification information about electronic devices is connected to an electronic device, and the plug receptacle side to which the electronic device is connected transmits to the power line its own identification information, etc. in coordination with the identification information of electronic devices from the adaptor. The controller receives this information and keeps track of locations of the electronic devices.