Product Selection Guide Page 784 Product Selection Guide-11th Edition

PSG11 784 LITHONIA LIGHTING OUTDOOR www.lithonia.com PRODUCT INFORMATION DESIGN GUIDELINES Floodlighting Design Guide IES Beamspread Classifications for general-purpose floodlighting The IES classification was formerly referred to as NEMA Type. The following outdoor design tips provide general guidelines for lighting design. These guidelines may not apply to all applications. Facade Lighting When lighting building facades with ground- mounted floodlights, there are three considerations: 1. Setback 2. Spacing 3. Aiming Sign Lighting When lighting a sign with ground-mounted flood- lights, there are three considerations: 1. Setback 2. Spacing 3. Aiming 1. Setback The recommended setback is three-fourths the building height. If a building is 30 feet tall, the rec- ommended setback is 22.5 feet from the building. Locating the floodlight closer to the building will sacrifice uniformity; setting it farther back will result in a loss of efficiency. 1. Setback When using ground-mounted floodlights to light a sign, the recommended setback is a distance equal to three-fourths the sign height. For example, the setback distance for a 12-foot by 6-foot sign would be 4.5 feet. Locating the floodlight closer will sacrifice uniformity while setting it farther back will result in a loss of efficiency. 2. Spacing The rule of thumb for spacing floodlights is not to exceed two times the setback distance. If the setback is 22.5 feet, the floodlights should not be placed more than 45 feet apart. 2. Spacing The rule of thumb for spacing floodlights is not to exceed two times the setback distance. If the setback is 4.5 feet, the floodlights should not be placed more than 9 feet apart. 3. Aiming The floodlight should be aimed at least two-thirds the height of the building. For example, if a building is 30 feet high, the recommended aiming point is approximately 20 feet high. After installation is complete, aiming can be adjusted to produce the best appearance. Mounting a full or upper visor to the floodlight can reduce unwanted spill light. 3. Aiming The floodlight should be aimed at least two-thirds up the sign. For example, if a sign is 6 feet tall, then the floodlight will be aimed approximately 4 feet high. After installation is completed, aiming can be adjusted to produce the best appearance. Mounting a full or upper visor to the floodlight can reduce unwanted glare. 22.5' setback 10' 20' 30' 12' 4-1/2' 6' 4' 2' 45' spacing 22.5' setback 10' 20' 30' 12' 4-1/2' 9' 4-1/2' 6' 4' 2' 20' 3/4 building height 10' 20' 30' 45' spacing 12' 4-1/2' 6' 4-1/2' 6' 4' 2' The IES beam spreads indicate the angular ranges (horizontally and vertically) through which the intensity of the floodlight is greater than 10% of its maximum intensity. This angular range is referred to as the "Field Angle." For example: FIELD ANGLE DEGREES IES TYPE BEAM DESCRIPTION 10 up to 18 1 Very narrow 18 up to 29 2 Narrow 29 up to 46 3 Medium narrow 46 up to 70 4 Medium 70 up to 100 5 Medium wide 100 up to 130 6 Wide 130 and up 7 Very wide Setback distance = 3/4 x building height 3/4 (30 ft.) = 22.5 ft. Setback distance = 3/4 x sign height 3/4 (6 ft.)= 4.5 ft. Spacing = 2 x setback distance 2 x 22.5 ft.= 45 ft. apart Spacing = 2 x setback distance 4.5 ft. x 2 = 9 ft. apart Aiming point=2/3 x building height 2/3 (30 ft.)=20 ft. high Aiming point = 2/3 x sign height 2/3 (6 ft.) = 4 ft. high Asymmetrical beam spread 138 (H) x 119 (V) Horizontal Vertical = IES 7 X 6 FLOODLIGHTING

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