DENO LED Lighting

When is a long RGBW LED strip better than RGB on a long run?

Choose RGBW whenever the same long run has to serve as everyday white light as well as a colour scene. RGB 'white' is a three-die mix: it carries a colour cast, renders skin and timber poorly, and is the least efficient state the board can sit in — which matters most on a 20 m run that stays white for most of its operating hours. A long RGBW LED strip adds a dedicated Ra 90+ white die at 2700K to 6500K, so white comes from a real white source and the colour channels are reserved for scenes.

Efficiency and colour quality over a long run

Producing white by driving three colour dies at once costs roughly twice the wattage of a dedicated white die for the same lux, and it does so at a CRI no specifier would accept for architectural light. Over 20 m that is both an energy penalty and a thermal one, since the extra watts also raise junction temperature and shorten life.

Splitting the job also simplifies the electrical design: the white channel can be dimmed conventionally and the colour channels driven only when a scene calls for them, which keeps average current — and therefore voltage drop — lower across the run.

Specifying long RGBW correctly

Four decisions define the board:

  • White CCT and CRI — 2700K, 3000K, 4000K or 6500K at Ra 90+
  • Four-channel driver and controller, matched to total run wattage
  • Constant-current regulation so the colour mix survives the run length
  • Cut unit — four channels need a longer repeat, typically 62.5–100 mm
  • Whether tunable white (CCT) would serve the project better than colour

Industry references and standards

More long run answers

Published by DENO LED Lighting — denoled.com, a custom long run LED strip manufacturer serving EU, Americas and Middle East projects.