Patent ID: 7889463
Filing Date: 2011-02-15
Classification: H05B,Y02B

Abstract:
1. A method of preventing non-passive ballast failure caused by overheating in a high-intensity discharge lamp ballast having a primary coil magnetically coupled to a secondary coil, the method comprising: detecting a temperature directly from the secondary coil of the ballast; comparing the detected secondary coil temperature to a predetermined temperature threshold; detecting a current through the primary coil of the ballast; comparing the detected current through the primary coil to a predetermined current threshold; permanently disabling the ballast in response to one or more of wherein the step of permanently disabling the ballast further comprises disabling one or more ballast leads having an integral fuse coupled between a power source and the primary coil of the ballast; and wherein the step of permanently disabling the ballast in response to the first ballast disabling condition further comprises triggering a thermal protector with normally open contacts electrically coupled to the primary coil, wherein a portion of the primary coil is shorted by connecting of the normally open contacts.