Control network for LED-based lighting system in a transit vehicle

摘要

A transit vehicle lighting system has a plurality of LED-based lighting fixtures for providing interior illumination. A control network comprises a plurality of slave nodes for controlling the LED-based lighting fixtures, and a master node for controlling the slave nodes. The master node may be connected to the slave nodes by a combined power/communication bus in a daisy chain fashion. The slave node may include a power regulator and a controller for providing a target current command to the power regulator, and may adjust the target current based upon temperature measurements or a recorded age of the LEDs. An optical sensor may provide automatic dimming. A reduced number of LEDs may be used in an emergency mode. The lighting fixture may include a ceiling panel fixture and a riser panel attachable by way of a hinge mechanism.

主权项

1. A distributed control network for a transit vehicle lighting system, comprising:
a plurality of LED-based lighting fixtures, each of said LED-based lighting fixtures comprising a plurality of light-emitting diodes (LEDs) for illuminating an area of a transit vehicle arranged in a linear array and flanked by a pair of reflective sidewalls angled outwards from the linear array and forming a cavity with the linear array at the base thereof, with a diffusive light-transmissive cover disposed over the cavity; a plurality of slave nodes for controlling the LED-based lighting fixtures; a master node in communication with said slave nodes; a battery power source coupled to said master node; a digital communications bus for communicating among the master node and the slave nodes; and a power bus interconnecting said master node and slave nodes; wherein said power bus is integrated with the digital communications bus in a plurality of power/data cable segments; wherein said master node is communicatively coupled to said slave nodes by connecting said slave nodes in a daisy chain using with said power/data cable segments; and wherein power derived from said battery power source is conveyed from said master node to said slave nodes through the power/data cable segments.