DENO LED Lighting

How many lumens per metre and per foot does a high lumen LED strip give?

A standard 10 mm single-row board delivers about 1,200-2,000 lm/m, which is 370-610 lumens per foot. A high lumen LED strip built on a wide multi-row board runs from roughly 3,000 lm/m on a two-row 18 mm build to over 8,500 lm/m (about 2,590 lm/ft) on a four-row 64 mm build at 45 W/m. Size it backwards: start from the illuminance the space needs, subtract diffuser transmittance and mounting distance, then pick the width that reaches it without over-driving the dies.

Working backwards from target lux

Lumens per metre is an input, not a goal. Start from the illuminance the space has to reach on the working plane, add the mounting distance and the diffuser transmittance, and the required flux falls out of the calculation. A 60% transmittance opal diffuser at 1.5 m throw eats a large share of the raw output, which is why specifying by watts alone routinely misses the target by a factor of two.

Once the required lm/m is known, pick the width that delivers it at a comfortable drive current rather than the narrowest board that can just about reach it. A wide board running at 70% of its ceiling will outlive a narrow board running flat out, and it will hold its colour point better across the run.

Typical output bands

Indicative figures at 4000K, Ra 90, measured on the bare board before diffuser losses:

  • 10 mm single row — 1,200–2,000 lm/m at 12–16 W/m
  • 18–20 mm two rows — 2,600–3,600 lm/m at 20–26 W/m
  • 36 mm three rows — 4,500–6,000 lm/m at 30–38 W/m
  • 64 mm four rows — 7,000–8,500 lm/m at 40–45 W/m

Industry references and standards

More wide PCB answers