Conventional building lighting systems, both residential and commercial, include numerous lighting units controlled by wall switches interconnected together by electrical wiring. Any changes and modifications to the lighting system are either constrained by the electrical wiring or require re-wiring of the lighting system. Conventional lighting system configurations are therefore inflexible and costly to modify.
Lighting system control configurations range from simple to complex. In one of the simplest control schemes, lights are turned on/off by dedicated wall switches located, typically, in the same room as the lights controlled by the wall mounted switches. Additionally, wall dimmers may be used to control (i.e., vary) the intensity of the lights. More complicated control functions such as grouping, preset lighting scenes, dimming and lighting based on ambient light, occupancy, and other factors can be implemented to provide intelligent control of the building lighting system. Such intelligent lighting system control may be implemented using an open, proprietary, or a standard lighting control command set such as, for example, the industry-standard DALI (Digital Addressable Lighting Interface). However, retrofitting and/or modifying a lighting system for DALI requires extra control wires for connecting a control box to the lighting units' ballast. Also, the conventionally wired DALI system has the disadvantage of added installation cost and retrofit inflexibility.
