Patent ID: 9538612
Date: 2017-01-03
CPC Classifications: H05B,Y02B

Claim:
1. A photocontrol apparatus to selectively provide alternating current (AC) power from an AC power source to a luminaire, the photocontrol apparatus comprising: an ambient light sensor having an output terminal which provides a signal responsive to an amount of light sensed by the ambient light sensor; an ambient light detection circuit including an input terminal and an output terminal, the input terminal electrically coupled to the output terminal of the ambient light sensor, the output terminal of the ambient light detection circuit provides an ambient light control signal which has a luminaire-on state and a luminaire-off state, the luminaire-on state indicates an ambient light level detected by the ambient light sensor is at a level such that AC power is to be provided to the luminaire, the luminaire-off state indicates the ambient light level detected by the ambient light sensor is at a level such that AC power is not to be provided to the luminaire; an AC sense circuit having an input terminal and an output terminal, the input terminal of the AC sense circuit electrically coupleable to the AC power source, the output terminal provides an AC sense signal indicative of at least one characteristic of the AC power source; a switch including an input terminal, an output terminal and a control terminal, the input terminal electrically coupleable to a line terminal of the AC power source, the output terminal electrically coupleable to a load terminal of the luminaire, the switch having a closed state in which the switch electrically couples the luminaire to the AC power source and an opened state in which the switch electrically decouples the luminaire from the AC power source; and a switch control circuit having a first input terminal, a second input terminal and an output terminal, the first input terminal electrically coupled to the output terminal of the AC sense circuit to receive the AC sense signal therefrom, the second input terminal electrically coupled to the output terminal of the ambient light detection circuit to receive the ambient light control signal therefrom, and the output terminal of the switch control circuit electrically coupled to the control terminal of the switch to provide a switch control signal thereto, the switch control circuit: