×

Lighting device

  • US 9,363,871 B2
  • Filed: 05/02/2013
  • Issued: 06/07/2016
  • Est. Priority Date: 05/04/2012
  • Status: Expired due to Fees
First Claim
Patent Images

1. A lighting control apparatus comprising:

  • a primary input power connection for connection to a primary power supply circuit external to the lighting control apparatus;

    a secondary input power connection for receiving secondary power from a secondary power supply; and

    electronic circuitry arranged to control power delivery to one or more light sources;

    wherein the electronic circuitry comprises;

    control circuitry for controlling delivery of power from said input power connections to one or more light sources; and

    sensing circuitry configured to sense and obtain a measure of impedance of the external primary power supply circuit that is coupled, in use, to the primary input power connection by applying one or more voltage or current pulses to the primary input power connection;

    wherein the control circuitry is arranged to determine a present operating state of the one or more light sources;

    wherein the control circuitry is arranged to determine a new operating state of the one or more light sources using the determined present operating state of the one or more light sources and the measure of said impedance obtained from the sensing circuitry;

    wherein the control circuitry is arranged to control delivery of power to the one or more light sources in dependence upon the determined new operating state of the one or more light sources; and

    wherein the control circuitry is configured to control delivery of power to the one or more light sources dependent of presence of primary power at the primary input power connection such that if the determined operating state of the one or more light sources is off, then the control circuitry does not deliver power to the one or more light sources even when primary power for powering the one or more light sources is available at the primary input power connection.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×