# LED street light pole height and spacing design method

#### LED street light pole height and spacing design method

Abstract for LED street light pole: The average illuminance of the road surface is one of the evaluation indexes of the city’s motor vehicle traffic roads and sidewalk lighting, and it is also a vital reference indicator for street lamp configuration. A city road should be configured or replaced with LED street lamps. Technically, it first involves the calculation of relevant indicators of lighting. Calculating with the “use factor” method is one of the more straightforward and more effective means.

The formula calculated by the “use factor” method is entirely the same as the conclusion of the study of traditional lighting theory. What we need to do is to input some experimental or theoretical data of the LED street lamp into the formula, get the result and compare it with the requirements of the road lighting design standard. These calculations are also necessary for the design, development, improvement, improvement, and marketing of LED street lamps.

##### First, concept

The use factor (U) is the ratio of the light flux directly on the road surface to the luminous flux emitted by all the light sources and is related to the height, elevation angle, arrangement, and road width of the street light fixture.

The luminous flux (Φ) is the sum of the energy emitted by the light source and received by the human eye. Indicates the amount of radiant energy per unit of time in lm. Other methods of expression: cd.sr (cd is the unit of luminous intensity: Candela. Sr is a unit of solid angle spherical power.

Illuminance (E) is the ratio of the luminous flux to the illuminated area, in lux lx. 1lx means that the flux of 1lm is evenly distributed over an area of 1 square meter of energy, i.e., lm/m2.

LED street light pole the average road surface illuminance (Eav) is the average value of the illuminance at each point measured or calculated at a predetermined position on the road surface by the relevant regulations.

The maintenance factor (k) is the ratio of the average illuminance or the average luminance on a predetermined surface after the lighting device is used for a specified period to the average illuminance or the average luminance obtained on the same surface when the device is newly mounted under the same conditions.

The installation height (H) of the luminaire is the vertical distance from the light center of the luminaire to the road surface.

The installation spacing (S) of the luminaire is the distance between two adjacent luminaires measured along the centerline of the road.

The cantilever length (XL) is the horizontal distance from the light center of the lamp to the edge stone adjacent to the side, that is, the horizontal distance that the filament extends or retracts into the edge stone.

The effective road width (Weff) for LED street light pole is the breadth of the theoretical road surface used for road lighting design. It is related to the actual width of the road, the cantilever length of the luminaire, and the layout of the luminaires.