Method and Apparatus for Operating a Group of Lighting Fixture Nodes

A method of selectively operating a group of networked and commonly powered lighting fixture nodes at reduced power, each of said networked lighting fixture nodes including at least one controllable lighting fixture, said method comprising:

• electrically coupling a single lighting fixture node of said lighting fixture nodes to a power circuit having a power circuit maximum output;
• broadcasting a query fixture network topology command to all of said fixture nodes
• wherein each of said lighting fixture nodes sends a fixture query command to at least one of any downstream of said lighting fixture nodes after receipt of said query fixture network topology command;
• determining a master lighting fixture node of said lighting fixture nodes which did not receive any said fixture query command;
• determining an expected nominal current of at least one fixture of said lighting fixture nodes;
• operating said one lighting fixture node and any of said lighting fixture nodes downstream from said one lighting fixture node at a nominal fixture power level that is less than a maximum power level of a respective of said lighting fixture nodes;
• identifying a current draw across at least said one lighting fixture node when said one lighting fixture node and any of said lighting fixture nodes downstream from said one lighting fixture node are being operated at said nominal fixture power level;
• reducing power consumption of at least some of said lighting fixture nodes based at least in part on comparing said expected nominal current draw to said current draw.

Alighting fixture network, comprising:

• a plurality of lighting fixture nodes in communication with one another, each of said lighting fixture nodes comprising:
• at least one lighting fixture having at least one light source;
• at least one adjustable driver driving said at least one light source at a selectively adjustable power level;
• a controller in communication with said adjustable driver;
• a communication system in communication with said controller and in communication with at least one other of said lighting fixture nodes;
• a power input receiving power directly from at least one of other of said lighting fixture nodes and a power circuit;
• and
• a power output for selectively transmitting power to at least one other of said lighting fixture nodes;
• wherein each said is operable in a power level determination mode;
• wherein in said power level determination mode each said controller causes a corresponding said driver to operate at a nominal fixture power level;
• wherein each said nominal fixture power level is less than a maximum power level of a respective of said driver;
• and
• wherein at least one said controller selectively communicates expected current draw data to at least one other of said lighting fixture nodes and selectively communicates actual current draw data from operation in said power level determination mode to at least one other of said lighting fixture nodes;
• wherein each said controller is operable in a reduced power mode;
• wherein in said reduced power mode each said controller causes a corresponding said driver to operate at a reduced power level;
• and
• wherein each said reduced power level is based at least in part on comparing said expected nominal current draw to said current draw.