Metal halide fixtures used to be the only light source for high bay lighting
but today fluorescent lighting is often the best lighting choice
Fluorescent T5/HO lamps can be used at heights of 30 feet or more yet will still
provide excellent vertical footcandles for storage racks.
The advantages of fluorescent light over metal halide are:
All lighting sources "depreciate" over time. That means the lamp puts out less light as it ages and is therefore less efficient. Depreciation can be as high as 64% for metal halide lamps on magnetic ballasts. Newer, electronic ballasts can raise that value to 86% but even then is below the 95% lumen maintenance of fluorescent lamps.
There is a great deal of debate as to whether better color rendering is important when the task is selecting cardboard. Some would argue that the yellow light of sodium light sources is sufficient while other would argue the fact that when humans are involved color rendering and color temperature are important. Our recommendation for warehouse lighting is a color temperature of 5000 degrees and color rendering of 86.
The "Instant on" issue is based on the fact that most aisles in racked storage buildings are vacant 80% of the time but illuminated 100% of the time when metal halide with magnetic ballasts are used. Electric ballasts can dim metal halide fixtures to approximately 50% but because of restrike time it is not practical to turn them off. Linear fluorescent fixtures can be turned off until occupancy sensors detect the presence of the operator. By setting the sensor to delay turning off the fixture for at least 15 minutes after vacancy and using programmed start ballasts lamp life can be maintained at acceptable levels.
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Narrow Beam Lighting Systems Recommended for tall stacked pallet rack aisles to achieve illumination in these narrow, sometimes darkened areas. Great for DC's, warehouses, and storage areas. |
Medium Beam Lighting SystemsRecommended for medium bay or low-racked, open-aisle industrial and retail lighting in warehouses, shop floors, distribution centers or staging areas. |
Wide Beam Lighting SystemsRecommended for wide open areas in manufacturing, shop floors, commercial, and mass market retail facilities |