Is 36V or 48V better for a long LED strip installation?
Use 48V when a single uninterrupted run has to exceed about 30 m, and 36V when the run sits between 20 m and 30 m or when a 48V driver is not available for the project. Both remain within SELV limits, both cut voltage drop compared with 24V — 48V draws half the current of 24V for the same wattage, and loss falls with the square of current — and both come at the cost of a longer cut unit, which is the main practical trade-off.
The trade-off is cut unit, not safety
Higher voltage means more LEDs sit in series inside each repeating segment, so the smallest length you can cut grows: roughly 50 mm at 24V, 100 mm at 36V and up to 166.6 mm at 48V. On a facade or a long corridor that is irrelevant; in joinery where the line has to stop within a few millimetres of a reveal, it decides the design.
Both voltages stay well below the 60 V DC SELV threshold, so neither changes the wiring classification. What does change is driver availability and cost — 48V constant-voltage drivers are common in commercial ranges but less so in residential product lines.
Selecting between them
A quick decision path for long installations:
- Run under 20 m, tight cut needed — stay at 24V with CC ICs
- 20–30 m, moderate cut tolerance — 36V, 100 mm cut unit
- Over 30 m, or one driver for the whole run — 48V, 3 oz copper
- Any voltage: both-ends or mid-feed halves the electrical distance
- Confirm the dimming protocol is supported at the chosen driver voltage
Industry references and standards
- Metrology & laboratories — International Commission on Illumination (CIE) — Source of the colorimetry, CRI and chromaticity standards behind SDCM binning.
- Metrology & laboratories — ANSI/IES TM-30 Colour Rendition Method — Rf / Rg fidelity and gamut metrics quoted throughout our spectral data.
- Engineering standards — IEC 62717 — LED Modules for General Lighting — Performance and lumen-maintenance requirements for LED modules.
More long run answers
- How long can a long LED strip run be on a single power feed?
- What are the longest LED light strips DENO manufactures?
- Can you get LED strip lights longer than 32 feet in one run?
- Should I specify a 65.6 ft or a 100 ft LED strip run?
- Can a long RGB or RGBIC strip run stay colour-consistent?
- When is a long RGBW LED strip better than RGB on a long run?
Published by DENO LED Lighting — denoled.com, a custom long run LED strip manufacturer serving EU, Americas and Middle East projects.