Transcript LED in LUMINAIRES - Mercer

LED in LUMINAIRES
Benefits of LED Luminaires
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Energy savings – Up to and Exceeding 50%
LED is environmentally clean / RoHS
(International standard : Restrictions on Hazardous Substances)
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Improved security – All fixtures stay on
Long life - 70,000 hrs and longer
Potentially huge maintenance savings
- re-lamp and ballast replacement up to $1000 each
HID vs LED Lumen Maintenance
100
Percent Rated Lumen Output
90
80
70
60
50
40
0
4
8
12
16
20
22
26
30
34
38
40
44
48
52
56
60
Hours of Operation
LED
LED Average
HID
HID Average
62
66
70
Operating Conditions
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Metal Halide (MH) and High Pressure
Sodium (HPS) require warm-up time and
cool-down/warm-up after power failure
vs. LED instant-on.
Fluorescent has poor efficiency in
cold weather (chart) vs. LED efficiency
improves with colder temperatures.
Technical Information
Basic LED Construction
Tj
Terms
Tj – Junction Temperature
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Affects Lumen Output
Affects Life Rating
Affects Color Stability Over Lifetime
Downward Delivered Lumens
Lumens per Watt (L/W)
Lumen Maintenance (L70 @70K)
Issues
Color Rendering (CRI)
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Scotopic vs. Photopic Issue
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HPS=22, MH=65 (typ. outdoor), LED=75,
Inc=100
Human Eye Response, ASSIST
Color Temperature
– Affects LED Lumen Output
– Many LED Fixtures Use 6000K
as Standard LED Color
(Yields Highest Ratings)
DOE CALiPER Program
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Commercially Available LED Product Evaluation
and Reporting
Reference www.ssl.energy.gov/caliper.html
2100K CCT
8460 Mean Lumens
(Equiv. to 100W
HPS)
6500K CCT
3300 Mean Lumens
Mesopic Street Lighting Report
see www.lrc.rpi.edu
Jan.31, 2008
XR-E Output by Color Temperature
120
107
93.9
100
87.4
Lumens
80
60
40
20
0
5500
5500
4500
4500
Color Temperature
COLOR TEMPERATURE
3500
3500
LED Integration
Luminaire Considerations
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Heat
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Dissipation
How is the LED heat moved out of the Luminaire?
Is the method reliable (heat rises, prone to plugging, etc.)?
Rated Life (L70), Output De-rate and Color Stability based on Thermal Design and Tj
What Kind of Light is Needed?
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Color Temperature : 6000K (highest out but cold) vs. 4500K (close to MH) vs. 3500K (warm)
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CRI based on LED selection
What
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Optic System is best?
Direct Delivery: higher efficiency, higher uniformity – visible source
Indirect Delivery: lower efficiency, dark spots, lower uniformity - hidden source
IESNA Types (II, III, IV, V)
Refractor optics (higher efficiency, more light control) vs. reflectors
Dark Skies / Light Pollution / BUG Ratings (replaced cut-off designations)
LED Considerations
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Reputable, Quality Manufacturer?
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LM-80 Data / Reports (IES Standard for Lumen Depreciation Reporting)
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Reliable Circuit Design – Series-Parallel (constant light level)
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Reliable LED Printed Circuit Board design and attachment (no clips or springs)
More Considerations
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Photometric Tests per LM-79 (IES Standard for SSL Photometry)
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Requires Absolute Photometry in lieu of Relative Photometry
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Independent Test Lab or in-house Lab (if available)?
LED Driver
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Separate driver or included on LED Boards?
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Driver placement in Luminaire (away from heat)
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Drive Current (350mA vs. 700mA vs. ? mA) ties into Thermal Design
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Reputable, Quality Manufacturer?
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Warranty
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Lightning / Electrical Surge Protection (IEC 6100-4-5 Standard)
Available Options
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Hi – Low Operation or Dimming
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Controls
Warranty
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50,000 to 100,000 hrs vs. 1 Year Warranty?
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How Long has Fixture Manufacturer been in Business?
Retrofit/Conversion
Issues
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How is Heat Dissipation Accomplished
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Affects Lumen Output
Affects Life Rating
Affects Color Stability
Photometry and LM-79 (in the fixture)
Driver
Warranty
Any questions?