DALI Short-Address Commissioner: Deterministic IEC 62386 Bus Provisioning

DALI Short-Address Commissioner walks through bringing up a DALI or DALI-2 lighting bus per IEC 62386: discovering control gear, resolving short-address collisions, assigning short addresses in the 0-63 range, programming groups (0-15) and scenes (0-15), configuring DT8 tunable-white color gear, and scheduling emergency battery duration tests.

It is built around a set of non-negotiable protocol invariants rather than loose guidance. Addressing and configuration commands such as INITIALISE (cmd 258), RANDOMISE (cmd 259), and SET SHORT ADDRESS (cmd 267) must be transmitted twice within a 100ms window or compliant gear silently ignores them.

import time

def send_dali_double_cmd(cmd_byte1: int, cmd_byte2: int):
    transmit_dali_frame(cmd_byte1, cmd_byte2)
    time.sleep(0.015)  # 15ms spacing
    transmit_dali_frame(cmd_byte1, cmd_byte2)

Sending INITIALISE starts a mandatory 15-minute commissioning timer on every ballast, inside which the master must finish a 24-bit random-address binary search (using SEARCHADDRH/M/L and COMPARE, cmd 265), isolate each unit, assign it a short address via PROGRAM SHORT ADDRESS, and immediately send WITHDRAW (cmd 266) so that fixture drops out of the remaining search. The session closes with TERMINATE (cmd 257). Every assigned address is meant to be verified visually via IDENTIFY or a RECALL MAX LEVEL/OFF toggle before it goes into a lighting schedule, and extending an existing line uses INITIALISE (without short address) rather than a global INITIALISE so already-commissioned fixtures 0-63 keep their programming.

Use it when bringing up, commissioning, or expanding a DALI or DALI-2 installation on gateways or gear from vendors such as Tridonic, Philips Dynalite, Helvar, Osram, or Lunatone - including resolving address-clash loops where multiple ballasts answer a broadcast query at once, and designing or scheduling DALI-2 Part 202 emergency lighting duration and function tests across staggered floor circuits.

Do not use it for DMX512/RDM stage lighting, 0-10V analog dimming, or proprietary wireless networks like Zigbee, Bluetooth Mesh, or Casambi. It is not a fault-diagnosis tool for dead ballasts or wiring problems - confirm basic DALI bus voltage (12V-20.5V DC) and current limits (<=250mA) first - and it does not cover building-wide KNX logic; its scope is strictly the DALI protocol layer.

Inputs are the physical DALI/DALI-2 bus state (existing addresses, PSU load, gear type) and the commissioning goal (greenfield discovery, single-ballast replacement, DT8 color/group setup, or emergency test scheduling). Output is a concrete, checked command sequence - address assignments mapped to physical fixtures, group and scene assignments, DT8 color-temperature commands, and a pre-emit checklist covering the 64-address ceiling, double-transmission timing, the 15-minute commissioning window, WITHDRAW discipline after each address, bus current headroom against the PSU rating, staggered emergency test scheduling, and a physical IDENTIFY verification step before anything is saved.

Applies to DALI and DALI-2 gear and gateways from vendors including Tridonic, Philips Dynalite, Helvar, Osram, and Lunatone, and to KNX/DALI gateway setups at the DALI-protocol layer specifically.

Lighting and building-automation technicians and integrators commissioning or expanding DALI/DALI-2 installations - greenfield bus bring-up, surgical replacement of a single failed ballast without disturbing the rest of the line, DT8 tunable-white and group/scene configuration, and emergency lighting test scheduling.