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AUTOMATIC LIGHT CONTROL SYSTEM

  • US 3,790,848 A
  • Filed: 04/10/1972
  • Issued: 02/05/1974
  • Est. Priority Date: 04/10/1972
  • Status: Expired due to Term
First Claim
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1. A lighting system comprising a power source, light means for illuminating a space, and control means for communicating the power source with the light means, the control means comprising a breakdown device having a first terminal and having a second terminal connected to ground, a first resistance connected between the first terminal and ground, resistance reducing means connected in parallel to the first resistance, an exterior photocell for sensing daylight conditions connected to the reducing means and for activating the reducing means, thereby maintaining a circuit through the breakdown device in the control means open during daylight conditions, a controller connected to the power source and to the first terminal for completing the circuit in the control means from the power source through the breakdown device when the controller is activated and when the exterior photocell is inactive during darkness, and switch means connected to the circuit and connected to the power source and to the light means for communicating the power source and the light means upon completion of the circuit in the control means.

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