What is the typical lifespan of an LED street light?
High-quality LED street lights typically last 50,000–100,000 hours (~10–15 years), depending on chip quality, heat dissipation, driver performance, and environmental conditions.
How does lumen depreciation affect LED street lights?
Lumen depreciation reduces brightness over time. Good-quality lamps maintain ≥70% luminous flux after 50,000 hours.
How should wattage be selected for different road types?
Residential roads: 20–60W
Urban main roads: 80–150W
Highways or large areas: 150–250W
Why is optical design important?
Proper optics ensure uniform illuminance, avoid glare, and minimize light pollution. Choose lamps with asymmetric, bat-wing, or Type II/III beam patterns for roads.
What are the recommended color temperature (CCT) and color rendering index (CRI)?
CCT: 3000K–6000K
CRI: ≥70, higher for urban or decorative roads
Which LED chips are preferred?
Brands like Cree, Bridgelux, Nichia, Lumileds; luminous efficacy ≥130 lm/W; forward voltage stable; low thermal resistance.
What specifications are essential for LED drivers?
Constant current output
Efficiency ≥90%
Over-voltage, over-current, short-circuit, and surge protection
Waterproof rating IP66 or higher
Why is heat dissipation critical?
Good heat management prolongs LED life and maintains brightness. Prefer die-cast aluminum heat sinks with fins, low thermal resistance, and convection-friendly design.
What materials are recommended for poles and housings?
Aluminum alloy or galvanized steel.
Anti-corrosion coating: hot-dip galvanization + powder coating.
Wind resistance rated for local climate.
What is the required IP rating?
Outdoor lamps: IP65 or above for waterproofing and dustproofing. Higher IP recommended for coastal or industrial areas.
