DALI2

DALI2
Name	DALI2
Type	lighting control protocol
Developer	ZVEI
Released	2012
Latest release	2019

DALI2 DALI2 is an industry specification for digital lighting control that extends and formalizes the original DALI protocol introduced by IEC 62386 standards work and industrial consortia such as ZVEI and IEC. It defines interoperable device classes, standardized commands, and conformance tests to enable multi-vendor ecosystems spanning luminaires, sensors, control gear, and building automation interfaces. The specification targets commercial, institutional, and architectural installations specified in procurement documents alongside standards like EN 15232 and guidance from organizations such as CENELEC and BIS.

Overview

DALI2 builds on the original DALI framework standardized under IEC 62386 and is managed through collaborative efforts of ZVEI, test houses, and manufacturers including Philips Lighting, OSRAM, Tridonic, and Zumtobel Group. It introduces device-type definitions for ballasts, LED drivers, sensors, and application controllers, promoting interoperability with gateways to systems like KNX, BACnet, and LonWorks. DALI2 also aligns with commissioning workflows used on major projects by consultancies such as Arup and WSP, and is cited in tender documents for clients including Siemens, Schneider Electric, and Honeywell.

Design and Architecture

The architecture of DALI2 is layered around the physical two-wire bus topology derived from earlier IEC work and integrates device addressing, scene control, and grouping semantics that mirror concepts found in ASHRAE and CIBSE guidance. The protocol supports point-to-point and broadcast messaging with up to 64 addresses per bus as specified by IEC 62386-101, and introduces extended features in subsequent parts like IEC 62386-251 for sensors and IEC 62386-207 for color control. Gateways and application controllers implement higher-level logic analogous to systems used in Siemens Smart Infrastructure and interface with building management systems conformant to BACnet/IP.

Hardware Components

Typical hardware in a DALI2 ecosystem includes control gear such as LED drivers produced by companies like Tridonic and Philips Lighting, line-powered DALI power supplies comparable to units from Mean Well, sensors and presence detectors by vendors such as Helvar and Acuity Brands, and application controllers or gateways from integrators like Schneider Electric and Siemens. The bus uses a two-wire low-voltage circuit and requires compliant power supplies and wiring practices often referenced in IEC 60598 installation guidance. Test and certification equipment used in laboratories such as TÜV Rheinland and VDE validate electrical and electromagnetic compatibility alongside interoperability matrices used by ZVEI test events.

Software and Protocols

DALI2 specifies command sets, device types, and mandatory features for conformance testing under suites administered by ZVEI and accredited test houses including UL and ETL. Firmware in DALI2 control devices implements parts of the IEC 62386 series and supports profiles for dimming curves, color control (including color temperature and RGBW) as laid out in EU and international project specifications like those from CIE and IESNA. Integration software and middleware often provide bridging to BACnet, Modbus, and KNX using gateways from companies such as Helvar and Tridonic, and commissioning tools from vendors like Lutron and Philips support offline/online commissioning workflows used by system integrators including Schneider Electric.

Applications and Use Cases

DALI2 is applied in office buildings procured by entities such as GSA, healthcare facilities designed by NHS Trusts and Mayo Clinic-affiliated projects, retail environments by chains like IKEA and Walmart, museums curated by institutions like the British Museum and Smithsonian Institution, and transport hubs managed by authorities including Transport for London and Munich Airport. Use cases include scene-setting and energy optimization in retrofits driven by regulations such as EU Energy Performance of Buildings Directive and projects aiming for certifications like LEED and BREEAM. DALI2’s sensor integration supports daylight harvesting and occupancy control strategies specified in standards like ASHRAE Standard 90.1 and referenced in consultancy reports from AECOM and Arup.

Development History and Timeline

DALI2 emerged as an evolution of the original DALI work documented under IEC 62386 with key milestones involving vendor consortia and test labs. Early DALI deployment was promoted in products from Philips' pre-2010 portfolios; formal DALI2 extensions and a centralized testing program were rolled out by ZVEI and participating manufacturers around 2012–2015, with subsequent harmonization of device types and additional parts added through 2019 under international working groups linked to IEC SC 34C. The conformance program and interoperability test events attracted participation from major lighting manufacturers, test bodies such as TÜV SÜD, and smart-building integrators including Schneider Electric.

Safety, Regulations, and Compliance

DALI2 devices and installations must comply with electrical safety and EMC standards like IEC 60598 and CISPR 15, and conformance testing is performed by bodies such as VDE, UL, and TÜV Rheinland. Procurement specifications often require certified interoperability demonstrated through ZVEI test reports and may reference national rules enforced by authorities such as BSI in the United Kingdom or DIN in Germany. Projects seeking green building ratings under LEED or BREEAM commonly cite DALI2-compliant control strategies in daylighting and energy credits, while large integrators coordinate compliance with local codes enforced by organizations like NFPA and IEC committees.

Category:Lighting control protocols