Patent ID: 8254072

Claim:
In a load center for distributing electrical power from electrical power utility lines to multiple branch circuits via a load center bus connected to said utility lines, each of the branch circuits having a circuit breaker coupled to a signal processor that is shared by all of the circuit breakers of the multiple branch circuits, a low voltage DC power supply comprising: a switch mode low voltage power supply connected to said processor for supplying said processor with a DC power input, and a line-derived power supply and a fault-derived power supply coupled between said utility and said switch mode power supply for supplying DC inputs to said switch mode power supply, said line-derived power supply including a step-down transformer coupled to the utility lines for producing a stepped-down AC voltage, and a rectifier for converting said stepped-down AC voltage to a first DC power input for said switch mode low voltage power supply, and said fault-derived power supply including a pair of current transformers on said utility lines for producing alternating signals proportional to the currents flowing in the utility lines connected to the load center bus, and rectifiers for converting the alternating signals produced by said current transformers to a second DC power input for said switch mode low voltage power supply.