Patent ID: 6731080
Filing Date: 2004-05-04
Classification: H05B

Abstract:
A luminaire having a plurality of ballasts connected to a plurality of lamps and further comprising:a plurality of relays connected to respective ones of the plurality of ballasts; a control device connected to each of said plurality of relays; and a control input for providing a control signal to said control device, said control device comprising a counter for counting and generating an output signal in response to said control signal and a decoder configured to receive said output signal and sequentially select which of said plurality of relays to actuate and thereby operate the corresponding ones of the plurality of ballasts in response to said output signal; wherein said control signal is a DC signal comprising pulses, said counter being operable to increment said output signal in response to each pulse, said decoder being configured to implement a truth table whereby all of the plurality of ballasts are powered on in response to a first one of said pulses, and then one or more subsets of the plurality of ballasts are powered down in response to subsequent ones of said pulses until all of the plurality of ballasts are powered down.