Addressable electrical outlets
Smart Appliances are defined that assist in reducing energy consumption or cost. The Smart Appliances communicate with Smart Energy sources via the power lines and in particular by injecting communications signals between the live plus neutral power lines on the one hand and the ground line on the other hand, the communications protocol allowing a power source to identify the electrical circuit to which an appliance is connected and thereby to route a selected type of power to the appliance on the correct electrical circuit for that appliance. An addressable electrical outlet is also disclosed as one form of Smart Appliance.
1. An addressable electrical power connector comprising:
terminals for connecting to live, neutral and ground conductors from a power distribution unit;
a signal injector and extractor circuit operative to inject, without electrical contact, on to a common mode of the live and neutral conductors, relative to the ground conductor, a data-bearing communications signal and further operative to extract, without electrical contact, a data-bearing communications signal from the common mode of the live and neutral conductors, relative to the ground conductor;
a low impedance connection, at the communications signal frequency, between the neutral and ground conductors, the low impedance connection comprising a capacitor in series with a damping resistor; and
a transceiver circuit operative to process a signal extracted by said signal extractor, and to decode said communications data, and further operative to encode communications data to be injected by said signal injector circuit, the transceiver circuit passing on said decoded communications data to permit control of the operation of an appliance connected to said connector when said data contains an address associated with said connector.
2. The addressable electrical power connector of claim 1 configured as an electrical power outlet, said decoded communications data being used to turn on or off the power flow out of the outlet.
3. The addressable electrical power connector of claim 1 configured as an electrical power outlet including a USB data connector, said decoded communications data being reformatted and routed to and from said USB data connector when the data does not terminate in the outlet.
4. The addressable electrical power connector of claim 1 configured as an electrical power outlet, having further terminals for the connection of live, neutral and ground conductors to a downstream electrical power outlet.
5. The addressable power connector of claim 1 configured as a power inlet connector of a Smart Appliance.
6. The addressable electrical connector of claim 1 configured as an adapter for plugging into an electrical outlet and providing a further outlet into which an appliance can be plugged.
7. The addressable electrical connector of claim 1 configured as an adapter for plugging into an electrical outlet and providing a further outlet into which an appliance can be plugged, and a USB socket for connecting data signals to and from said appliance to said transceiver.
8. The addressable electrical connector of claim 1 configured as a Ground Fault Interrupting outlet, in which said signal extractor also extracts from said common mode a 60 Hz signal indicative of a ground leak and interrupts power output from the outlet in the case of a ground leak.
9. The addressable electrical connector of claim 1 configured as a Ground Fault Interrupting outlet, in which said signal extractor also extracts from said common mode a 60 Hz signal indicative of a ground leak, interrupts power output from the outlet in the case of a ground leak and encodes an indication of ground leak circuit interruption with a recipient address into a signal modulated on to said carrier frequency signal, and injects the modulated carrier frequency signal on to said common mode of neutral and live conductors relative to the ground conductor for transmission to said recipient.
10. The addressable electrical connector of claim 1 configured as a Ground Fault Interrupting outlet, in which, when said decoded address is that of the outlet itself, and said decoded data is indicative of a reset, resets a previously occurred ground fault trip.
11. The addressable electrical connector of claim 1 wherein values for the capacitor and damping resistor are selected so as to render the shape of the communications signal transmission frequency response substantially independent of the length of the live, neutral and ground conductors from the power distribution unit.
12. The addressable electrical connector of claim 1 wherein the transceiver circuit is further operative to perform error correction decoding on signals extracted by said signal extractor circuit, and to perform error correction encoding on signals injected by said signal injector circuit.
13. The addressable electrical connector of claim 1 wherein the transceiver circuit is further operative to perform error correction on said communications data.
14. The addressable electrical connector of claim 1 wherein said error correction comprises generating and comparing a Cyclic Redundancy Check code for each received packet of data.