| In many fields of application, dimmable lighting systems become more and more important. Up to now, light control has usually been realised by use of analog 1-10 V interfaces.
Dimmable electronic ballasts with 1-10 V interface prolong the lamps’ life cycle, increase their degree of efficiency and reduce energy consumption. Besides these advantages, these devices have some disadvantages as well:
 Via the 1-10 V interface, the electronic ballasts are only dimmed; switching is
still realised by use of a separate power line.
The dimmable electronic ballasts from different manufacturers have different
characteristic curves.
The lamps of one control line might provide different light levels due to the
resistance of the control line.
There is no feedback about the actual state of the lighting system.
DALI bridges the gap existing between LON network and lamp. DALI (Digital Addressable Lighting Interface) is a new, standardised interface for electronic ballasts, that has been developed by the leading European ballast manufacturers.
Individual dimming and switching via one data line by means of ballast addresses are the basic functions. Up to 64 individually addressed ballasts can be connected to the DALI line. They can be divided into up to 16 groups. Every ballast provides 16 scene memory units to store light levels so particular atmospheres can be recalled directly.
The LON DALI Controller REG-S 4DIM, 8DIM and 16DIM allow independent switching and dimming of four, eight or 16 lighting groups respectively according to the LonMark profiles. Furthermore, they provide the scene control of the DALI devices.
The electronic DALI ballasts communicate bidirectionally, i.e. DALI ballast can propagate their current state to other DALI devices. Appropriately equipped lamps can announce failures to the LON DALI Controller. The latter transmits the message via the LON network to a building management centre or via a LON TCP/IP gateway to any other place in the world.
The LON DALI Controllers are integrated in the DALI system. They control all connected DALI ballasts and provide an interface between LON and DALI bus. For easier configuration of the controller and all devices connected to the DALI bus, a LNS plug-in is available. It integrates all DALI devices into the LON bus system. The systems integrator needs neither any special accessory devices nor software to commission the DALI bus.
The controllers provide a cost-effective solution for intelligent light control - completely integrated in cross-system building automation. |
