DALI-2 systems and components

DALI-2 systems & components

The main DALI-2 product types required for a complete lighting-control system are: 

MAIN PRODUCT TYPES

► Control gear (e.g. LED drivers) – Provide power to light sources

Control devices, which have two main types: ► Application controllers – Use information, make decisions and send commands to the control gear ► Input devices  – Sensors (e.g. light, occupancy) and devices to enable user input

► Bus power supplies – Provide power required for DALI communication

A DALI-2 product can contain more than one product type e.g. an application controller with integrated bus power supply.

 

 

An example of a DALI lighting-control system. The DALI bus carries DALI power and data on the same pair of wires. Each DALI subnet can have 64 control gear and 64 control devices. Control gear provide power to LEDs and other light sources. Control devices include application controllers (which make decisions and send commands), and input devices such as sensors, switches and push-button devices. A bus power supply is required, providing up to 250 mA and typically 16V to the DALI bus. A gateway to an external network is often integrated into an application controller. 

 

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Control gear

Control gear, such as LED drivers, provide power to light sources and are normally directly connected to the lamp(s).

The DALI protocol supports different control-gear types, such as ballasts for fluorescent lamps, and control gear for self-contained emergency lighting.

In DALI-2, each DALI subnet can have 64 control gear and 64 control devices.

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Application Controllers

Application controllers are the “brains” of a DALI-2 system. 

They use information, make decisions and send commands to the control gear.

Application controllers can use information from any source, including:

• Control gear
• Input devices
• Other application controllers
• External devices/buses/systems

Single-master or multi-master variants are allowed:

Single-masters	Multi-masters
Only one allowed on the DALI bus	More than one can be used on the same bus
Receiver is optional
May allow polling of input devices, or checking status of control gear	Supports event-driven operation of input devices
	Uses a short-address

 

 

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Input Devices

Input devices are fairly simple devices that provide user-derived and environmental information to the lighting-control system.

Includes sensors that provide information for automated control, and devices enabling user inputs to allow occupants to make adjustments e.g. dimming, colour, scene recall etc

Examples include push-buttons, sliders, occupancy sensors, and light sensors.

Input devices are multi-master. They can be polled, but are normally used in event-driven mode.

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DALI-2 products

Search for certified DALI-2 products in the online Product Database. You can filter the search according to the features required.

 

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Cabling and bus power supplies

The DALI bus carries DALI power and data on the same pair of wires, typically using standard 2-core cable (1.5 mm²).

The polarity of the wires does not have to be observed, and free wiring topology is allowed.

The maximum cabling length (the distance between the furthest-apart devices) is 300m.

Each DALI-2 system requires a bus power supply, which can be a standalone device or integrated with another device (e.g. an application controller).

Bus power supplies provide typically 16 V and up to 250 mA to provide power to devices connected to the bus.