Patent ID: 8009042

Claim:
A radio-frequency load control system with occupancy sensing comprising: a load control device connected between an AC power source and an electrical load, said load control device containing an RF receiver circuit for receiving radio frequency signals; and first and second battery-powered occupancy sensors, each occupancy sensor fixable to a surface of a room in which said electrical load is located for transmitting an RF signal in response to the presence of an occupant in said room, said second occupancy sensor spaced from the location of said first occupancy sensor, each occupancy sensor comprising an enclosed plastic housing including at least one battery, a detector for sensing the presence or absence of occupants in said room, and a RF transmitter circuit for producing said RF signal which is modulated to indicate the presence or absence of said occupant in said room, the RF signals of said occupancy sensors having respective identifying information to identify themselves to the load control device; wherein said load control device receives said RF signals transmitted by said occupancy sensors and controls the current supplied to said electrical load in a predetermined dependence on the detection of an occupancy or a vacancy in said room.