US Patent 10529202 Motion detector alert device

The motion detector alert device comprises a detector unit and an annunciator unit. The detector unit comprises a threaded base and a threaded socket. The threaded base of the detector unit screws into a motion sensing light fixture in place of the bulb. The bulb screws into the threaded socket. The detector unit monitors electrical energy passing from the motion sensing light fixture to the bulb and transmits a signal when the light fixture energizes the bulb. The annunciator unit may be located inside of a building. Responsive to reception of the signal sent from the detector unit, the annunciator unit may produce an audible sound to alert occupants of the building that motion has been sensed outside.