Patent ID: 8068014

Claim:
A system for communicating between a first control circuit portion and a remote second control circuit portion over an electrical power wiring of a building that receives power from an AC voltage source, the first control circuit portion having a user actuable control for remotely controlling an electrical load controlled by the second control circuit portion, the system comprising: a transmitter in the first circuit portion for transmitting control information over the power wiring to the second circuit portion; a receiver in the second circuit portion for receiving the control information transmitted over the power wiring by the first circuit portion for controlling the load; and further wherein the first and second circuit portions each include a current responsive element coupled to the building power wiring for establishing a current signal loop in the building power wiring between the first and second control circuit portions for the exchange of the control information, the current responsive elements of the first and second circuit portions coupled in series electrical connection with the AC voltage source and with each other and further coupled so that load current from the AC voltage source for powering the load is conducted through the current responsive elements, further wherein said current responsive elements each comprise a current transformer having a winding, the windings of the current transformers coupled in series electrical connection with the AC voltage source and with each other.