The lighting controls scope of work is based upon the philosophy that occupants of commercial office buildings prefer natural light to electric light. The lighting controls system specified by the Times Company for its new headquarters building is a DALI (Digital Addressable Lighting Interface) based system with dimmable fixtures throughout the interior space. This allows the system to dim down the electric lighting in response to daylight admittance. It also provides for variable target set points for illuminance levels at the work plane. The Times Company intends to establish and adjust target set points on a departmental basis. The lighting control sequences are described within the specification 16575. These sequences utilize occupancy sensors, photo sensors, switches and a time clock to control the lighting in the interior space on each floor. The emergency lighting system is also described within the specification. The lighting control sequences are tied to Control Intent Diagrams that divide up the space on each floor into its various control zones. The overall intent is to provide electric light only when the space is occupied and to provide as little electric light as is necessary to achieve the target set point for the work plane in a given department. A department usually occupies multiple floors.
This specification has been made public in order to assist design professionals by providing an example of a daylight harvesting, fully dimmable lighting controls system that has been market tested. This specification combined with reflected ceiling plans, lighting fixture layouts and DALI ballast specifications was competitively bid and led to the award of the lighting controls system contract on October 4, 2004. The DALI ballasts (refer to specification 16510) were awarded as an integral part of the lighting controls contract.