The benefits of HCL are rooted in how light influences our biological clock—a roughly 24-hour cycle known as the circadian rhythm.

Light and the Brain

• Light is the primary environmental cue that synchronises our circadian rhythm to the external day-night cycle.

• Specialised photoreceptors in the eye—called intrinsically photosensitive retinal ganglion cells (ipRGCs)—detect light, particularly blue wavelengths, and send signals directly to the suprachiasmatic nucleus (SCN) in the brain.

• The SCN regulates processes like melatonin production, body temperature, and alertness.

Daylight vs Artificial Light

• Natural daylight changes in intensity and colour throughout the day, supporting energy during the morning and day, and promoting rest in the evening.

• Most artificial lighting is static—offering neither the intensity nor spectral variation needed to stimulate natural biological responses.

• This disconnect contributes to sleep disruption, reduced productivity, and even long-term health impacts such as metabolic disorders, mood disturbances, and cardiovascular strain.

What the Research Says

• Exposure to cool, blue-rich light in the morning has been shown to:

  • Increase alertness

  • Improve cognitive performance

  • Enhance mood

• Exposure to warmer light in the evening supports:

  • Melatonin production

  • Improved sleep quality

  • Reduced anxiety and stress levels

Organisations like the WELL Building Standard, CIE, and European Lighting Experts have increasingly included Human Centric Lighting in their guidelines—recognising its importance for workplace design, healthcare, education, and residential living.

To achieve effective HCL, you need more than a tuneable luminaire. The intelligence comes from the controls.

Until recently, this often meant complex systems, custom programming, and costly commissioning. But now, many of the required capabilities are available within established lighting control protocols—particularly DALI.

DALI DT8: Making HCL Accessible

DALI DT8 devices allow:

• Single-address control of both CCT and dimming

• Standardised configuration across manufacturers

• Simple integration into larger DALI networks

This means specifiers and engineers can deliver HCL using familiar tools and platforms, without reinventing the wheel or dramatically increasing costs.

Manual Control Still Has a Role

Not all applications require full automation. In many environments, local control of colour temperature and brightness still offers clear benefits. For example:

• Warmer tones in the evening create comfort in homes or hospitality settings

• Cooler, higher-intensity lighting can boost productivity in offices, schools, and healthcare

There are now many standalone and intuitive control options—from rotary dials to app-based sliders—that let users interact with their light in a human-centric way, without needing a full control system.

The reality is, not all light is created equal. And as the science of lighting evolves, so too does our ability to specify systems that do more than just illuminate.

Decades of research support the connection between light quality and human health—from sleep quality and hormone regulation to focus and emotional well-being.

What’s changed is that HCL is now practical:

• It uses widely accepted protocols like DALI

• It relies on readily available hardware

• It can be installed, commissioned, and maintained using established processes

The key is correct specification—choosing the right luminaires, drivers, and controls, and commissioning them carefully to work in harmony.

We provide a wide range of LED drivers that are compatible with human centric lighting projects.  Click the links below to find out more

LM Series

• 75-100W Constant Voltage Driver
• 2 Channel CCT dimmable
• Screwless push fit terminal
• Toolless cable restraint
• 0.1% dimming
• Control protocols: Mains, 0/1-10V, DALI-2 DT8, DMX 512/RDM
• Push/switch dim on all variants to control brightness and colour temperature

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SE20 Series

• 20W Constant Voltage

• 2 Channel CCT Dimmable

• Dip switch selectable output

• Terminal Based

• 0.1% dimming

• Control protocols: 0/1-10V, DALI-2 DT8, DMX 512/RDM

• Push/switch dim on all variants to control brightness and colour temperature

VIEW RANGE