DALI (Digital Addressable Lighting Interface) is a sophisticated bidirectional digital dimming protocol standardized under IEC 62386 for professional LED power supplies. It uses a two-wire bus (typically 9–16V DC) to transmit digital commands between a controller and individual LED drivers or groups of drivers. Each driver can have a unique address (up to 64 per DALI line, expandable with routers), allowing precise, individual or group control of brightness, on/off, scene setting, and status feedback.
Unlike analog methods such as 0-10V or TRIAC, DALI provides two-way communication: the driver can report faults, energy consumption, operating hours, and lamp status back to the central controller. Dimming is highly accurate (typically 0.1%–100% in 256 steps) with smooth transitions and minimal flicker, thanks to digital PWM or current control. It supports advanced features like scheduling, daylight harvesting, occupancy sensing, and integration with building management systems (BMS).
DALI is ideal for large-scale commercial, office, retail, hospitality, and smart building projects where centralized control, energy management, and maintenance diagnostics are essential. Installation requires a dedicated DALI bus (polarity-free, daisy-chain or star topology), but it offers excellent scalability and future-proofing.
Modern DALI LED drivers are highly efficient (>85–92%), incorporate full protection features, and often support DALI-2 or D4i extensions for IoT and wireless integration. They represent the professional standard for intelligent lighting systems.
