LEDKE Technology Co., Ltd. LEDKE Technology Co., Ltd.
LEDKE Technology Co., Ltd.


How to choose LED street light wattage?

Author : Henry Huang Date : 6/28/2013 7:36:16 AM

Many people often encounter such a problem, that how much wattage LED lights can replace 400 watt high pressure sodium lamp or halogen lamp? A simple proportional relationship is: LED lights: HPS = 1:4. In fact, to choose how much wattage need go through rigorous testing, and finally meet LED street lights industry standards.

Tools and steps to testing the locations:

First: Test conditions and areas:
1) Test road width 12m, pavement material is concrete, test condition is unilateral street lamp arrangement, the other side light off. Light is 10 meters high, the lamp arm length 1.5 m (extended road section of about 0.9 m), elevation angle about 10 degrees.

2) Test supposing area 12m × 33m, quality evaluation will be based on this area. Considering the narrow road demand less on road lateral light distribution, also providing application area 9m × 33m data for different widths of roads reference.

Second: the testing time and data:
The final data is the average value for the three testing, the light fades is calculated according to the first and third result, the time span is 113 days, light time about 1200 hours.

Third: Adopt lumen, efficiency and horizontal illumination uniformity to evaluate the power:
1) Set application lumen as the area total road luminous, formula is: average area illumination × area;
2) Set the application luminous efficiency as the road effective light efficiency, which is calculated as application lumen ÷ input power;
3) Lateral illumination uniformity reference to vertical illumination, that’s illuminance minimum and maximum ratio of lateral illumination.