Flood Light Application: General Lighting
Pole mounted flood lights are great general area lighting for parking lots, storage yards, and other lard open areas. When installing these fixtures, the following factors should be considered:
- Mounting Height
- Pole Spacing
- Vertical Aiming
- Horizontal Aiming
Mount flood lights one half the distance across the entire area to be lighted.
Mounting Height = 1/2 Distance to be lighted
1/2 x 40 ft. = 20 ft.
When installing poles, the 4 Times Rule should be used. Each pole should be spaced four times the mounting height from each other.
Pole Spacing = 4 x Mounting Height
4 x 20 ft. pole = 80 ft. apart between poles
The 2/3 Rule is used for vertical aiming. The flood light is aimed 2/3 the distance across the area to be lighted and at least 30 degrees below horizontal.
To minimize glare, the aiming point distance should never exceed twice the mounting height. If the pole height is 20 feet, the vertical aiming point should not extend past 40 feet.
2/3 x 40 ft. = 27 ft. Aiming Point
If multiple flood lights are mounted on a single pole, horizontal aiming must also be considered. Each flood light should follow the 2/3 Rule for vertical aiming, as described above. If the flood lights have a horizontal NEMA type 6 or 7, the fixtures can be aimed up to 90 degrees apart.
Source: Lithonia Lighting