LED Traffic Light Specifications: Voltage, Wattage, IP Rating

A traffic light datasheet is full of abbreviations—IP65, cd, nm, V AC—that decide whether a signal will actually work in your project. Misreading one line can mean a signal that is too dim for the road, incompatible with the local voltage or unable to survive the climate. Understanding the core specifications lets you compare products on facts instead of marketing.

This guide decodes the parameters that matter most when you read or write a traffic signal specification.

Electrical specifications

Input voltage

Traffic lights are built for a specific supply: common options include 12/24 V DC (often for solar or vehicle systems) and 85–265 V AC or 110/220 V AC for mains power. The signal must match the supply available at the installation. Specifying the wrong voltage is one of the most common and most preventable ordering errors—confirm the site voltage before you order.

Power consumption (wattage)

Wattage tells you how much power each aspect draws. LED signals are far more efficient than old incandescent units, typically consuming only a few watts per aspect. Lower power reduces operating cost and is especially important for solar systems, where every watt affects panel and battery sizing.

Frequency and surge protection

For AC signals, confirm the mains frequency (50/60 Hz) and whether the unit includes surge or transient protection. Outdoor signals are exposed to lightning-induced surges and grid fluctuations, so built-in protection significantly improves field reliability.

Optical specifications

Luminous intensity and class

Luminous intensity, measured in candelas (cd), determines how bright the signal appears and from how far it can be read. Standards such as EN 12368 define intensity classes for different road conditions. The required class depends on road speed and ambient light—always match the specified class to your tender or national requirement.

Chromaticity (color coordinates)

Signal colors are defined by chromaticity coordinates so that "red" is unmistakably red to every driver. Standards specify the allowed color regions for red, yellow (amber) and green. Compliant chromaticity is essential for safety and for passing inspection.

Viewing angle

The viewing angle describes how widely the light is distributed horizontally and vertically. It must match the road geometry—too narrow and drivers off-axis cannot see the signal; too wide and it may be misread from the wrong lane. Lens design controls the viewing angle.

Environmental specifications

IP rating (ingress protection)

The IP rating describes how well the enclosure resists dust and water. The first digit is dust protection, the second is water. For outdoor traffic signals, IP65 or higher is typical—dust-tight and protected against water jets. The rating must suit the installation environment, from rain to coastal humidity.

Operating temperature

Signals must operate across the local climate, often from well below freezing to high summer heat. Confirm the rated operating temperature range matches your region, including cold starts in winter and heat inside a sun-exposed housing.

Mechanical specifications

Diameter (200/300/400 mm), housing material, weight and mounting interface determine whether the signal physically fits your poles and brackets. Confirm the mounting method and wind-load rating, especially for large 300–400 mm heads and solar installations.

How to specify a traffic light correctly

When you write or review a specification, state the diameter, aspect and color configuration, input voltage, luminous intensity class or standard, IP rating, operating temperature and mounting method. A complete specification lets the manufacturer quote exactly and prevents the misunderstandings that cause wrong shipments.

Traffic light specification FAQ

What voltage do traffic lights use?

Common options are 12/24 V DC for solar or vehicle systems and 85–265 V AC or 110/220 V AC for mains power. Always confirm the supply voltage at the installation before ordering.

What does IP65 mean on a traffic light?

IP65 means the enclosure is dust-tight (6) and protected against water jets from any direction (5). It is a common minimum rating for outdoor traffic signals exposed to rain.

What is luminous intensity in a traffic signal?

Luminous intensity, measured in candelas, describes how bright the signal appears and how far away it can be read. Standards such as EN 12368 define required intensity classes for different road conditions.

How many watts does an LED traffic light use?

LED signals are highly efficient, typically drawing only a few watts per aspect—far less than incandescent units. Exact wattage depends on size and design and matters most for solar system sizing.

GAOQIAO provides detailed specifications for every LED traffic light, with OEM/ODM customization of voltage, optics and IP rating. Browse the traffic light range, or request a datasheet for your project.