DLC Releases Draft 1 of Horticultural Lighting V4.0 Specification
DLC Releases Draft 1 of Horticultural Lighting V4.0 Specification
On November 7, 2024, the DesignLights Consortium (DLC) released the first draft of the Horticultural Lighting V4.0 Standard, addressing the following key aspects:
The Photosynthetic Photon Efficacy (PPE) must exceed 2.5 μmol/J (with a tolerance of -5%).
Due to the relatively lower number of horticultural light sources applying for DLC certification compared to the full fixture category, DLC has removed the standard scope for the horticultural light source category to simplify the requirements.
【Proposed removal of lamp categories
In 2021, Hort V2.1 introduced several new product qualification pathways for Dc-powered products, liquid cooled products, and several lamp types, since then, all new categories have seen participation and QPl listings have been actively growing, except for lamps. With the lack of uptake around lamps, Hort V4.0 proposes to simplify the overall Technical Requirements and application process by removing the qualification pathway for lamps. 】
Mainly focusing on two aspects:
- Defining the coverage of LED models with different dominant wavelengths acceptable under LM80 limitations.
【LM-80 applicability claims where the difference from the nominal peak or dominant wavelength of the LM-80 tested LED to the nominal peak or dominant wavelength of a different LED is beyond +/-15nm will be rejected.】
- Tunable spectrum products are categorized into custom spectrum tuning and preset spectrum tuning.
【Customizable Spectra - This category of spectrally tunable products allows precise and dynamic control over the spectral output by allowing the user to adjust individual control points. These control points can be adjusted continuously through a variety of user interfaces such as physical or digital sliders representing LED type or wavelength, a color wheel, or other approaches. For purposes of this document, the variety of interfaces used for custom spectral control will be referred to as "custom spectral controllers".
Predefined Spectra - This category of spectrally tunable products allows the user to select from a set of predefined spectral options, often referred to as "spectral recipes," that have been design by the manufacturer with intentions for specific plants, plant growth stages or desired outcomes (e.g., vegetative growth, flowering, fruiting).】
