Integration into Building Automation Systems
Lighting systems provide a life safety function, assisting in security or lighting evacuation pathways from a building. Lighting systems may be integrated with fire alarm systems, security systems, or emergency power generators. In the case of a fire alarm or loss of normal power, the lighting control system may turn on key emergency lighting fixtures.
Data and information from a lighting system is also an integral part of an overall energy strategy and at some facility or business level needs to be considered with HVAC systems, metering, and building plug loads. Monitoring the number of hours that the lights are operated and the number of times lights are turned on provides information in estimating lamp life, which can be used to schedule group relamping.
Lighting systems have a communication protocol called digital addressable lighting interface or DALI for ballasts and relay switches, which was developed in the 1990s. For a DALI implementation, each lamp uses dimming ballast and each lamp has its own network address. DALI uses a two-wire low-voltage wiring scheme in a bus topology, with the bus providing both power and control signals to the ballast.
DALI is an open-source protocol based on standard IEC60929, which specifies performance requirements for electronic ballasts. Each DALI controller (called a busmaster) can handle up to 64 addresses and 16 groupings. Because the DALI protocol is solely for use by lighting control systems its integration to other systems may require a protocol translation with systems using BACnet or LonWorks. DALI has been extended into shading control, and wired network connectivity has been supplemented with wireless connectivity.
Programming lighting control systems use smart technology infrastructure at the higher levels of the control system. Technology evolution is introducing increased use ofstructure cable, Ethernet, and TCP/IP protocols.