Floodlights

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Return to '''[[Freestyle Equipment List]], [[TV Glossary of Terms]], [[Snow and Weather Glossary]]''', '''[[Working with Snow]], [[Freestyle Skiing]]''' Return to '''[[Freestyle Equipment List]], [[TV Glossary of Terms]], [[Snow and Weather Glossary]]''', '''[[Working with Snow]], [[Freestyle Skiing]]'''
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-*1 Wikipedia Reference see ''Floodlights'' [http://en.wikipedia.org/wiki/Floodlights_(sport)] 

Revision as of 17:07, 12 July 2010

Floodlights are broad-beamed, high-intensity artificial lights often used to illuminate outdoor playing fields while an outdoor sports event is being held during low-light conditions.
Floodlights are broad-beamed, high-intensity artificial lights often used to illuminate outdoor playing fields while an outdoor sports event is being held during low-light conditions.

Floodlights are broad-beamed, high-intensity artificial lights often used to illuminate outdoor playing fields while an outdoor sports event is being held during low-light conditions.

Types of floodlight:The most common type of floodlight is the Metal Halide lamp which emits a bright white light, however most commonly used for sporting events are high pressure Sodium floodlights which emit a soft orange light, similar to that of street lights; SON lamps have a very high lumens per watt ratio making them a cost effective choice where certain lux levels have to met.

Types of floodlight:The most common type of floodlight is the Metal Halide lamp which emits a bright white light, however most commonly used for sporting events are high pressure Sodium floodlights which emit a soft orange light, similar to that of street lights; SON lamps have a very high lumens per watt ratio making them a cost effective choice where certain lux levels have to met.


Contents

Outdoor sports lighting

Outdoor sports lighting is a specialized form of area lighting.

Pole locations, mounting heights, and luminaire aiming are selected to light the ball in play. There is also a need to minimize fixture brightness or glare in the eyes of the players and spectators. Selected areas such as the infield of a baseball field may be highlighted to insure sufficient light for the batter and faster play in the infield.

Specific design considerations are given with each sports lighting design.


Luminaire Selection:

Luminaires are available in a variety of beam spreads or NEMA beam types as well as construction types. In the typical layout section, recommended luminaire quantities are listed in the adjacent tables to provide the highest lighting efficiency consistent with uniform lighting. Luminaires from different manufacturers do not have the same performance characteristics even though they may have the same NEMA beam type.


Basic lamp type

The basic lamp type used for sports lighting is high intensity discharge (HID). These HID systems primarily use 400W, 1000W and 1500W metal halide or 400W and 1000W high pressure sodium lamps. While mercury lamps have been used extensively in the past for sports lighting, they are no longer recommended because of their lower efficiency.

The life of HID lamps vary from 1,500 to 24,000 hours. The most common lamps used today are the 1000 and 1500 watt metal halide lamps. The 1500 watt lamp has the best combination of lamp efficiency (115+ LPW) and life (3,000 hours) for use in most sports lighting venues.

Where longer lamp life or lower mounting heights are desired, 1000 watt metal halide lamps are recommended. Approximately 50% more 1000 watt lamps are required to achieve the same lighting levels as compared to 1500 watt lamps.

This difference increases the cost of installation due to greater quantities and added structural requirements for poles and foundations.


Warm Up & Restrike Time:

HID lamps require 3-7 minutes to warm up if a momentary power interruption occurs. These lamps require the same amount of time to return to full luminance. Some form of instant-on lighting, usually one or two incandescent luminaries per pole, is recommended to provide lighting during the 1-15 minute restrike time. In addition, the incandescent (quartz) type fixtures should be used for emergency lighting of the fields when required. HID fixtures with optional “hot lamp restrike” capability are available. This option is for “hot restrike” only and does not provide “instant light” when the fixtures are cold started.

Stroboscopic Effect:

The light output of HID lamps follows the 60-cycle current waveform. The stroboscopic effect will cause a moving object to appear to flicker or jump from position to position due to the cycling waves of light. It is most pronounced when the object is small and traveling over 50 feet per second. If the object is moving toward the player or the player is following the motion of the object, strobe will be less noticeable. This annoyance can be minimized by using three-phase power with HID lamps.


Metal

Halide lamps, do not produce as much stroboscopic effect and can be used successfully on single-phase power.

Design Criteria: The design information in this guide is based on published lamp and luminaire performance that are inherent in their design. Normal manufacturing tolerances cause changes in a lamp’s electrical characteristics and lumen output. Light changes in reflector finish and lamp position can alter the photometric distribution of the luminaire. Changes in the ballast and line voltage will also alter the output of the lamp.

As a result of these variations average illumination levels can be expected to vary with 10% of the design value. Individual point-by-point footcandle values can vary more than this, especially when only a few luminaires are involved, resulting in little overlap between luminaires.

Aiming Diagrams:

Aiming diagrams describe the unique lighting design for each field. This information contains directional aiming instructions for each luminaire, luminaire selection, NEMA types, point-by-point footcandle values, pole positioning, field layout, and other design criteria. The aiming instructions should be followed closely. A difference of a few degrees in aiming can make a significant difference in the resulting light level and uniformity. Consult our lighting application designers for a custom design.


Illumination Levels:

Snow albedos can be as high as 90%; this, however, is for the ideal example: fresh deep snow over a featureless landscape. Over Antarctica they average a little more than 80%. If a marginally snow-covered area warms, snow tends to melt, lowering the albedo, and hence leading to more snowmelt (the ice-albedo positive feedback).
Snow albedos can be as high as 90%; this, however, is for the ideal example: fresh deep snow over a featureless landscape. Over Antarctica they average a little more than 80%. If a marginally snow-covered area warms, snow tends to melt, lowering the albedo, and hence leading to more snowmelt (the ice-albedo positive feedback).

The suggested light levels in this book are based on the Illuminating Engineering Society “Recommended Practice for Sports and Recreational Area Lighting,” RP-6. Sports lighting for television requires special design considerations. Requests for TV sports lighting should be directed through your local sales office.

Also See

References

  • 1 Wikipedia Reference see Floodlights [1]
  • CHM Industries CHM Sports Lighting [2]
  • International Dark-Sky Association (IDA) — Information Sheet #185Sports and Recreational Area Lighting http:[//data.nextrionet.com/site/idsa/is185.pdf][Image:Nps27C7.tmp.pdf]

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