Patent ID: 7906913

Claim:
A device used with a direct current power source for energizing a lamp, said device comprising: a first and second input channel, each input channel being selectively connected the power source for providing current to the lamp for energizing said lamp; a current sensing component connected to the second input channel between the power source and the lamp, said current sensing component producing a measurable signal as a function of current provided by the second input channel; a bypass switch connected to the second input channel in parallel with the current sensing component, said bypass switch having an open mode, and said bypass switch having a closed mode for bypassing the current sensing component and conducting current provided by the second input channel for energizing the lamp; and a controller connected to the current sensing component and the bypass switch, said controller identifying the input channel that is providing current to the lamp as a function of the measurable signal and for controlling the mode of the bypass switch based on the identified input channel wherein the controller operates the bypass switch in the closed mode when the second input channel is the identified input channel and wherein the controller operates the bypass switch in the open mode when the first input channel is the identified input channel.