Product Selection Guide Page 785 Product Selection Guide-11th Edition

785 PSG11 LITHONIA LIGHTING OUTDOOR PRODUCT INFORMATION DESIGN GUIDELINES Floodlighting Design Guide 90 AIMING POINT AIMING LINE Aim at least 30 to avoid glare. 13' 40' 27' Flag Lighting When using ground-mounted floodlights to light flags there are three considerations: 1. Setback 2. Spacing 3. Aiming Pole-Mounted Floodlights Pole-mounted floodlights are commonly used for general area lighting applications such as parking lots and storage yards. When using pole-mounted floodlights, there are four considerations: 1. Mounting height 2. Spacing 3. Vertical aiming 4. Horizontal aiming 1. Setback The recommended setback for lighting a flag is one-third times the pole height. If the pole is 30 feet tall, the floodlight should be set back a distance of 10 feet away from the pole. 2. Spacing When more than one pole is added, pole placement is a concern. The "4 times" rule of thumb for spacing indicates that a pole should be placed four times the mounting height from the adjacent poles. If a flood is mounted on a 20-foot pole, space the poles 80 feet apart. 1. Mounting Height The recommended mounting height is one half the distance across the area to be lighted. If the area to be lighted is 40 feet across, the lowest recommended mounting height is 20 feet. 2. Spacing Ideally, three floodlights are recommended to light a flag. The floodlights should be placed approximately 120 apart. 3. Vertical Aiming A single floodlight uses the two-thirds rule of thumb for vertical aiming. The fixture is aimed two-thirds of the distance across the area to be lighted and at least 30 below horizontal. If the area to be lighted is 40 feet across, the recommended aiming point is 27 feet. Additionally, to minimize glare, the recommended aiming point distance should never exceed twice the mounting height. If a pole is 20 feet high, the verti- cal aiming point should not exceed 40 feet out. 2 (20 ft. mtg. ht.) = 40 ft. 3. Aiming The recommended aiming point for each floodlight is the center of the flag or the top of the pole. Mounting a full or upper visor to the floodlight can reduce unwanted spill light. 4. Horizontal Aiming When an additional floodlight is added to a single pole, horizontal aiming also must be considered. First, each floodlight should be vertically aimed according to the two-thirds rule. As long as the floodlight has a horizontal NEMA 6 or 7 beamspread, the floodlights can be aimed up to 90 apart. 30' 10' Aim at least 30 to avoid glare 13' 40' 27' 40 ' 20' Setback distance = 1/3 x pole height 1/3 (30 ft.) = 10 ft. Pole spacing = 4 x mounting height 4 (20-ft. pole) = 80 feet between poles Aiming point = 2/3 across distance to be lighted 2/3 (40 ft.) = 27 ft. aiming point Mounting height = 1/2 distance to be lighted 1/2 (40ft.) = 20 ft. 3 floodlights spaced 120 apart 120 120 120 FLOODLIGHTING

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