Cree XLamp XM-L LED 10,000-Lumen High Bay

Cree® XLamp® XM-L LED
10,000-Lumen High-Bay Reference Design
Table of Contents
Introduction
Introduction......................................................... 1
This application note details the design of a replacement
Design approach/objectives................................... 2
high-bay luminaire using Cree’s XLamp XM-L LED. The
The 6-step methodology........................................ 2
high flux output and efficacy offered by the XM-L LED
1. Define lighting requirements............................. 2
make it a particularly strong candidate for use in a
2. Define design goals......................................... 5
high-bay luminaire. The performance of the XM-L LED
3. Estimate efficiencies of the optical, thermal &
means that it is not necessary to use hundreds of LEDs
electrical systems........................................... 5
4.Calculate the number of LEDs........................... 8
CLD-AP96 rev 0A
application note
to match the light output of traditional metal halide and
fluorescent high-bay lighting.
5.Consider all design possibilities......................... 8
www. cree.com/Xlamp
6. Complete the final steps: implementation and
An XM-L LED-based high-bay luminaire not only offers
analysis......................................................... 9
energy efficiency benefits but its long lifetime also
Conclusions........................................................14
reduces maintenance costs in typically hard-to-reach
Special thanks....................................................14
industrial and commercial applications.
Reliance on any of the information provided in this Application Note is at the user’s sole risk. Cree and its affiliates make no warranties or representations
about, nor assume any liability with respect to, the information in this document or any LED-based lamp or luminaire made in accordance with this
reference design, including without limitation that the lamps or luminaires will not infringe the intellectual property rights of Cree or a third party.
Luminaire manufacturers who base product designs in whole or part on any Cree Application Note or Reference Design are solely responsible for the
compliance of their products with all applicable laws and industry requirements.
Copyright © 2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo
Copyright ©® 2010 Cree, Inc. All rights reserved. The information in this document is subject to change without notice.
and XLamp are registered trademarks of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For
Cree, the Cree logo and XLamp are registered trademarks of Cree, Inc.
warranty information, please contact Cree Sales at [email protected] Other trademarks, product and company names are the property of their
respective owners and do not imply specific product and/or vendor endorsement, sponsorship or association.
Cree, Inc.
4600 Silicon Drive
Durham, NC 27703
USA Tel: +1.919.313.5300
XLamp xm-l 10,000-lumen High-bay Reference Design
Design approach/objectives
In the “LED Luminaire Design Guide”1 Cree advocates a six step framework for creating LED luminaires and lamps. All
Cree reference designs use this framework, and the design guide’s summary table is reproduced below.
Step
Explanation
1. Define lighting requirements
2. Define design goals
3. Estimate efficiencies of the
thermal & electrical systems
optical,
4. Calculate the number of LEDs needed
5. Consider all design
choose the best
possibilities
and
6. Complete final steps
•
The design goals can be based either on an existing fixture or on the application’s lighting
requirements.
•
•
Specify design goals, which will be based on the application’s lighting requirements.
Specify any other goals that will influence the design, such as special optical or environmental
requirements.
•
•
•
Design goals will place constraints on the optical, thermal and electrical systems.
Good estimations of efficiencies of each system can be made based on these constraints.
The combination of lighting goals and system effiiciencies will drive the number of LEDs needed
in the luminaire.
•
Based on the design goals and estimated losses, the designer can calculate the number of LEDs
to meet the design goals.
•
•
With any design, there are many ways to achieve the goals.
LED lighting is a new field; assumptions that work for conventional lighting sources may not
apply.
•
•
•
•
•
Complete circuit board layout.
Test design choices by building a prototype luminaire.
Make sure the design achieves all the design goals.
Use the prototype to further refine the luminaire design.
Record observations and ideas for improvement.
Table 1: Cree 6-step framework
The 6-step methodology
The goal of the design is an LED-based high-bay luminaire that can replace high-intensity discharge (HID) and 54-watt
fluorescent T5 and T8 luminaires in commercial, industrial and warehouse applications. As a replacement luminaire, this
design uses a form factor that is similar to traditional high-bay lighting currently in use.
1. Define lighting requirements
Table 2 shows a ranked list of desirable characteristics to address in a high-bay luminaire design.
Importance
Critical
Characteristics
Units
Illuminance distribution
footcandles (fc)/lux (lx)
Electrical power
watts (W)
Lifetime
hours
Luminous flux
lumens (lm)
Manufacturability
1 LED Luminaire Design Guide, Application Note AP15, www.cree.com/xlamp_app_notes/luminaire_design_guide
Copyright © 2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo and XLamp® are registered trademarks
of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact Cree Sales at [email protected]
2
XLamp xm-l 10,000-lumen High-bay Reference Design
Importance
Important
Characteristics
Units
Operating temperatures
°C
Operating humidity
% RH
Correlated Color Temperature (CCT)
K
Color Rendering Index (CRI)
100-point scale
Ease of installation
Table 2: Ranked design criteria for a high-bay luminaire
Table 3 summarizes the ENERGY STAR® requirements for solid-state luminaires.2 There are no ENERGY STAR requirements
for high-bay luminaires.
Characteristic
Requirements
Light source life requirements:
all luminaires
The LED package(s) / LED module(s) / LED array(s), including those incorporated into LED light engines or
GU24 based integrated LED lamps, shall meet the following L70 lumen maintenance life values (refer to Lumen
Maintenance Requirements in the next section):
•
•
•
25,000 hours for residential grade indoor luminaires
35,000 hours for residential grade outdoor luminaires
35,000 hours for commercial grade luminaires
Lumen maintenance life projection claims in excess of the above requirements shall be substantiated with a TM-21
lumen maintenance life projection report.
Lumen maintenance
requirements: directional and
non-directional luminaires
The LED package(s) / module(s) / array(s), including those incorporated into LED light engines or GU24 based
integrated LED lamps, shall meet the following
•
•
•
L70(6k) rated lumen maintenance life values, in situ:
L70(6k) ≥ 25,000 hours for residential indoor
L70(6k) ≥ 35,000 hours for residential outdoor, or commercial
Compliance with the above shall be documented with a TM-21 lumen maintenance life projection report as detailed
in TM-21, section 7. The report shall be generated using data from the LM-80 test report for the employed LED
package/module/array model (“device”), the forward drive current applied to each device, and the in situ TMPLED
temperature of the hottest LED in the luminaire. In addition to LM-80 reporting requirements, the following
information shall be reported:
•
•
•
•
•
•
sampling method and sample size (per LM-80 section 4.3)
test results for each TS and drive current combination
description of device including model number and whether device is an LED package, module or array (see
Definitions)
ANSI target, and calculated CCT value(s) for each device in sample set
Δ u’v’ chromaticity shift value on the CIE 1976 diagram for each device in sample set
a detailed rationale, with supporting data, for application of results to other devices (e.g. LED packages with
other CCTs)
Access to the TMPLED for the hottest LED may be accomplished via a minimally sized hole in the luminaire housing,
tightly resealed with a suitable sealant if created for purposes of testing.
All thermocouple attachments and intrusions to luminaire housing shall be photographed.
CCT requirements: all indoor
luminaires
The luminaire (directional luminaires), or replaceable LED light engine or GU24 based integrated LED lamp (nondirectional luminaires) shall have one of the following nominal CCTs:
•
•
•
•
•
2700
3000
3500
4000
5000
Kelvin
Kelvin
Kelvin
Kelvin
Kelvin (commercial only)
The luminaire, LED light engine or GU24 based integrated LED lamp shall also fall within the corresponding 7-step
chromaticity quadrangles as defined in ANSI/NEMA/ANSLG C78.377-2008.
Color rendering requirements:
all indoor luminaires
The luminaire (directional luminaires), or replaceable LED light engine or GU24 based integrated LED lamp (nondirectional luminaires) shall meet or exceed Ra ≥ 80.
2 ENERGY STAR Program Requirements, Product Specification for Luminaires (Light Fixtures), Eligibility Criteria, Version 1.1, www.
energystar.gov/ia/partners/prod_development/new_specs/downloads/luminaires/Final_Luminaires_Program_Requirements.pdf
Copyright © 2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo and XLamp® are registered trademarks
of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact Cree Sales at [email protected]
3
XLamp xm-l 10,000-lumen High-bay Reference Design
Characteristic
Requirements
Color angular uniformity
requirements: directional solid
state indoor luminaires
Throughout the zonal lumen density angles detailed above, and five degrees beyond, the variation of chromaticity
shall be within 0.004 from the weighted average point on the CIE 1976 (u’,v’) diagram.
Color maintenance
requirements: solid state indoor
luminaires only
The change of chromaticity over the first 6,000 hours of luminaire operation shall be within 0.007 on the CIE 1976
(u’,v’) diagram, as demonstrated by either:
Source start time requirement:
directional and non-directional
luminaires
Light source shall remain continuously illuminated within one second of application of electrical power.
Source run-up time
requirements: directional and
non-directional luminaires
Light source shall reach 90% of stabilized lumen output within one minute of application of electrical power.
Power factor requirements:
directional and non-directional
luminaires
Total luminaire input power less than or equal to 5 watts: PF ≥ 0.5
Transient protection
requirements: all luminaires
Ballast or driver shall comply with ANSI/IEEE C62.41.1-2002 and ANSI/IEEE C62.41.2-2002, Class A operation.
The line transient shall consist of seven strikes of a 100 kHz ring wave, 2.5 kV level, for both common mode and
differential mode.
Operating frequency
requirements: directional and
non-directional luminaires
Frequency ≥ 120 Hz
Noise requirements: directional
and non-directional luminaires
All ballasts & drivers used within the luminaire shall have a Class A sound rating.
Electromagnetic and radio
frequency interference
requirements: directional and
non-directional luminaires
Power supplies and/or drivers shall meet FCC requirements:
•
•
•
the IES LM-80 test report for the employed LED package/array/module model, or
as demonstrated by a comparison of luminaire chromaticity data in LM-79 reports at zero and 6,000 hours, or
as demonstrated by a comparison of LED light engine or GU24 based integrated LED lamp chromaticity data
in LM-82 reports at zero and 6,000 hours.
Total luminaire input power greater than 5 watts:
Residential: PF ≥ 0.7
Commercial: PF ≥ 0.9
Note: This performance characteristic addresses problems with visible flicker due to low frequency operation and
applies to steady-state as well as dimmed operation. Dimming operation shall meet the requirement at all light
output levels.
Ballasts and drivers are recommended to be installed in the luminaire in such a way that in operation, the
luminaire will not emit sound exceeding a measured level of 24 BA.
•
•
Class A for power supplies or drivers that are marketed for use in a commercial, industrial or business
environment, exclusive of a device which is marketed for use by the general public or is intended to be used
in the home.
Class B for power supplies or drivers that are marketed for use in a residential environment notwithstanding
use in commercial, business and industrial environments.
Table 3: ENERGY STAR luminaire requirements
The DesignLights™ Consortium provides requirements for a high-bay luminaire.3
Application
Characteristic
Minimum light output
Zonal lumen density
High-Bay and Low-Bay Fixtures for
Commercial and Industrial Buildings
High-Bay-Aisle Lighting
10,000 lm
10,000 lm
≥ 30% 20–50°
≥ 50%, 20–50°
≥ 30%, 0–20°
Minimum luminaire efficacy
70 lm/W
60 lm/W
Allowable CCTs (ANSI C78.377-2008)
< 5700 K
< 6000 K
Minimum CRI
L70 lumen maintenance
Minimum luminaire warranty
70
70
35,000 hours
35,000 hours
5 years
5 years
Table 4: DesignLights Consortium high-bay luminaire requirements
3 Technical Requirements Table v1.6, DesignLights Consortium Qualified Products List - Non-Residential Applications, www.designlights.
org/solidstate.manufacturer.requirements.php
Copyright © 2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo and XLamp® are registered trademarks
of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact Cree Sales at [email protected]
4
XLamp xm-l 10,000-lumen High-bay Reference Design
2. Define design goals
Table 5 shows the design goals for this project.
Characteristic
Unit
Minimum Goal
Target Goal
Light output
lm
10,000
10,000
Power
W
150
< 150
Luminaire efficacy
lm/W
66
70
Lifetime
hours
50,000
50,000
CCT
K
5,000
5,000
CRI
100-point scale
Power factor
75
> 75
0.9
> 0.9
Table 5: Design goals
3. Estimate efficiencies of the optical, thermal & electrical systems
We used Cree’s Product Characterization Tool (PCT) tool to determine the drive current for the design.4
For the 10,000-lm target, we estimated 93% optical efficiency and 85% driver efficiency. We also estimated a solder
point temperature of 85 °C.
LED System Comparison Rep
The PCT output highlighted in Figure 1 shows that, at 2.4 A, sixteen XM-L LEDs provide sufficient light output to meet
1
the design goals.
System:
10,000
Target Lumens :
93
Optical Efficiency:
Current (A)
LED 1
Model
Flux
Optic
Tj (ºC)
T6 [280]
Price
SYS # LED SYS lm tot
1.500
23
1.600
22
1.700
21
1.800
20
1.900
19
2.000
18
2.200
17
2.400
16
2.600
15
2.800
15
3.000
14
0.000
#N/A
Figure 1: PCT view
of the
LED 2
Model
Cree XLamp XM-L {CW/NW/WW}
$
85
10225.8
10313.8
10338.8
10302.9
10208.3
10056.9
10191.8
10200.8
10092.2
10579.7
10290.6
#N/A of
number
Flux
Price
-
SYS W
120.09
123.5
126.17
128.1
129.26
129.65
136.04
140.81
143.89
155.62
155.99
#N/A used
LEDs
(none)
Tj (ºC)
$
2
-
SYS lm/W
85.1
#N/A
83.5
#N/A
81.9
#N/A
80.4
#N/A
79
#N/A
77.6
#N/A
74.9
#N/A
72.4
#N/A
70.1
#N/A
68
#N/A
66
#N/A
#N/A
#N/A
and drive current
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
#N/A
This document is provided for informational purposes only and is not a warranty or a specification. For product specifications, please see the data
Copyright © 2009-2011 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree, the Cree logo a
Because this reference design is targeted as a replacement high-bay luminaire, the design has a form factor similar to
incumbent luminaires. The optic is a commercially available 16-inch diameter reflector commonly used in HID high-bay
4PCT is available at pct.cree.com
Copyright © 2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo and XLamp® are registered trademarks
of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact Cree Sales at [email protected]
5
XLamp xm-l 10,000-lumen High-bay Reference Design
luminaires. The LED array size and arrangement is designed to fit this reflector. To maximize the luminaire’s light output,
we painted the inside of the reflector with reflective white paint.
Figure 2: High-bay reflector
Thermal Requirements
The thermal solution is a key factor in the success of this reference design, as the LEDs are concentrated at the center
of the luminaire. To make this design feasible, we worked with two partners to design and fabricate a custom metal core
printed circuit board (MCPCB) and heat sink.
MCPCB
As shown in Figure 4, this high-bay luminaire design has sixteen XLamp XM-L LEDs
arranged in a closely spaced 4 x 4 rectangular array. To handle the high power density
we used a special copper MCPCB from Rayben.5 As shown in Figure 3, where a typical
MCPCB has a copper trace layer and a dielectric layer to transfer heat to the aluminum
base layer and on to the surrounding environment, the Rayben MCPCB in this design
has a “micro heat exchanger” (MHE) layer to transfer heat to the copper base layer and
offers greater heat transfer capability. The electrically neutral thermal path of the XM-L
LED makes this possible.
Figure 3: MHE thermal
substrate
5Model MHE 301, Rayben, www.rayben.com/English/contact/contact.asp
Copyright © 2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo and XLamp® are registered trademarks
of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact Cree Sales at [email protected]
6
XLamp xm-l 10,000-lumen High-bay Reference Design
Figure 4: MCPCB with XM-L LEDs
Heat Sink
This reference design uses a custom vapor-chamber heat sink by Steady Heat &
Mass Transfer Technology Academy Ltd, shown in Figure 6.6 As Figure 5 illustrates,
the heat sink has a unique vapor chamber design to enhance thermal conductivity
and heat dissipation. A special liquid is vacuum sealed in a chamber formed between
the heat source, in this design the MCPCB, and the heat fins. The heat from the
MCPCB causes the liquid to evaporate; the vapor condenses on the cooler part of the
chamber to enhance cooling and collects on the base near the heat source to repeat
the cycle.
Figure 5: Heat sink design
Figure 6: Heat sink attached to heat sink support
6 Model HBEXC-98D160L200-S, Steady Heat & Mass Transfer Technology Academy Ltd., www.cnvc.cc
Copyright © 2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo and XLamp® are registered trademarks
of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact Cree Sales at [email protected]
7
XLamp xm-l 10,000-lumen High-bay Reference Design
We performed thermal simulations to verify this thermal design is sufficient. Figure 7 shows the thermal simulation
results for the design. The simulated solder point temperature (TSP) is 72 °C.
Figure 7: Thermal simulation of XM-L high-bay heat sink
Driver
We used a market-ready constant-current driver that fits within the heat sink support and matches the design’s current
and voltage range.7 The high-bay luminaire design can also accommodate locating the driver separate from the luminaire.
Figure 8: Driver
4. Calculate the number of LEDs
Using Cree’s PCT, we determined that sixteen XLamp XM-L LEDs produce sufficient light to meet the 10,000-lm design
goal.
5. Consider all design possibilities
There are many ways to design an LED-based high-bay luminaire. This reference design aims to show that the XM-L LED
enables a high-bay luminaire offering superior performance.
The XM-L LED offers a wide range of color temperatures. We selected a neutral white LED for this high-bay luminaire
design, shown highlighted in Table 6.
7Model HLG-150-54A, Mean Well USA, Inc., www.meanwellusa.com
Copyright © 2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo and XLamp® are registered trademarks
of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact Cree Sales at [email protected]
8
XLamp xm-l 10,000-lumen High-bay Reference Design
AME : 10875-G.IES
CCT Range
Color
Min.
MATION (From Photometric File)
Neutral White
3,700 K
Max.
5,000 K
Base Order Codes
Min. Luminous Flux
@ 700 mA (lm)
Order Code
Group
Flux (lm)
T4
240
XMLAWT-00-0000-000LT40E3
T5
260
XMLAWT-00-0000-000LT50E3
T6
280
XMLAWT-00-0000-000LT60E3
Table 6: XM-L order codes
6. Complete the final steps: implementation and analysis
2
Bay Reference
Design
Using the methodology
described above, we determined a suitable combination of LEDs, components and drive conditions.
This section describes how Cree assembled the high-bay luminaire and shows the results of the design.
e Textured High Bay Reflector
Prototyping Details
We verified the
dimensions to ensure a correct fit.
NAIRE1.OUTPUT
= component
10443 LM
Following the recommendations in Cree’s Soldering and Handling
6 VDC2.and
113.7 Watts
Application Note for the XM-L LED, with an
appropriate solder paste and reflow profile, we reflow soldered the LEDs to the MCPCB.8
3. We ran the LED DC input wires through an enclosed channel in the heat sink.
The channel runs the length of the heat sink and insulates the LED DC input
wires from the heat and moisture in the heat sink.
4. We soldered the LED DC input wires to the MCPCB.
N.A. (absolute)
lit up.
N.A. (absolute)
6. We applied a thin layer10463
of thermal conductive compound to the back of MCPCB
and attached it to the heat sink with screws.
cy
N.A.
7. We secured the heat sink support to the end of the heat sink with screws.
ng (LER)
92
8. We connected the LED DC input wires to the driver DC output wires with
113.7
connectors.
1.00
9. We fit the LED driver into the heat sink support. This is an optional step as the
Directtype. This driver can be located apart from the
driver is a remote standalone
0)
0.64
luminaire or a centralized
dedicated power line can be directly wired to the
70)
0.64
luminaire.
to the heat sink with screws.
onal) 10.We secured the reflector
1.00
11.We performed final testing
Circular
0)
0.00 ft
0)
1.33 ft (Diameter)
0.00 ft
5. We tested the connection by applying power to the LEDs and verified the LEDs
Figure 9: Assembled high-bay
luminaire ready to test
8Cree XLamp XM-L LED Soldering and Handling, Application Note AP54, www.cree.com/~/media/Files/Cree/LED%20Components%20
and%20Modules/XLamp/XLamp%20Application%20Notes/XLampXM_SolderingandHandling.pdf
/sq.m)
e
Average
45-Deg
Average
90-Deg
Copyright © 2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo and XLamp® are registered trademarks
of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact Cree Sales at [email protected]
9
XLamp xm-l 10,000-lumen High-bay Reference Design
Results
Thermal Results
Cree verified the board temperature with a thermocouple to confirm that the thermal dissipation performance of the heat
sink aligns with our simulation. As shown in Figure 10, the measured solder point temperature was 61 °C, which shows
that the heat sink is sufficient for this design.
TSP
Solder Point Temperature
61 °C
T2
PCB Temperature
T3
Heat Sink Temperature
56 °C
50 °C
Figure 10: Thermal measurement
Based on the measured solder point temperature of 61 °C, the junction temperature (TJ) can be calculated as follows.
TJ = TSP + (LED power * LED thermal resistance)
TJ = 61 °C + (7.8 W * 2.5 °C/W)
TJ = 81 °C
Estimated LED lifetime
Figure 11 shows the calculated and reported lifetimes, determined using the TM-21 projection algorithm, for the XM-L
LED at a 2-A input current at three solder point temperatures. The duration of Cree’s XM-L HEW LM-80 data set is 6000
hours at a 2-A drive current. The TM-21 methodology limits the projection to six times the duration of the LM-80 data
set.
Copyright © 2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo and XLamp® are registered trademarks
of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact Cree Sales at [email protected]
10
XLamp xm-l 10,000-lumen High-bay Reference Design
TM-21 Lifetime Report
LED
I
Data Set
Tsp
Sample Size
Test Duration
α
β
Calculated Lifetime
Reported Lifetime
1
45°C
25
6,048 hrs
1.459E-07
9.847E-01
L70(6k) = 2,340,000 hours
L70(6k) > 36,300 hours
XLamp XM-L White
2000 mA
2
55°C
25
6,048 hrs
9.543E-07
9.887E-01
L70(6k) = 362,000 hours
L70(6k) > 36,300 hours
3
85°C
25
6,048 hrs
2.155E-06
9.834E-01
L70(6k) = 158,000 hours
L70(6k) > 36,300 hours
Reported
Calculated
Reported
110
105
100
95
% Luminous Flux
90
85
45°C (LM-80)
80
55°C (LM-80)
85°C (LM-80)
75
45°C (TM-21)
70
55°C (TM-21)
65
85°C (TM-21)
60
55
50
1,000
10,000
100,000
1,000,000
10,000,000
Time (hours)
Figure 11: XM-L TM-21 data
Figure
showsis the
calculated
and reported
XM-L or
LED,
interpolated
from the
data shown
Figure
11,
This 12
document
provided
for informational
purposeslifetimes
only and is for
not the
a warranty
a specification.
For product
specifications,
pleaseinsee
the
datameasured
sheets available
at www.cree.com.
at the
61 °C
TSP for the XM-L LED in this design. Although this design operates at a slightly higher current
Copyright © 2011 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree, the Cree logo and
thanXLamp
the 2-A
level oftrademarks
the TM-21
dataInc.
set, Cree’s experience with the XM-L LED gives us reason to expect that, with a
are registered
of Cree,
reported L70(6k) lifetime greater than 36,300 hours and a calculated L70(6k) lifetime of 302,000 hours at 2 A, the
Copyright © 2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo and XLamp® are registered trademarks
of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact Cree Sales at [email protected]
11
XLamp xm-l 10,000-lumen High-bay Reference Design
TM-21 Lifetime Report
high-bay luminaire to easily meet the 35,000-hour DesignLights Consortium L70 lumen maintenance requirement when
operating at a measured 2.3 A.9
Ts1
XLamp XM-L White
2000 mA
Tsi (Interpolated)
Ts2
55°C
61°C
85°C
328.15 K
334.15 K
3191.23
1.5965E-02
1.136E-06
9.861E-01
L70(6k) = 302,000 hours
L70(6k) > 36,300 hours
L70(6k) = 302,000 hours
L70(6k) > 36,300 hours
358.15 K
LED
I
Tsp
Tsp
Ea/kB
A
α
β
Calculated L70
Reported L70
Calculated Lifetime
Reported Lifetime
9.543E-07
9.887E-01
L70(6k) = 362,000 hours
L70(6k) > 36,300 hours
110
45°C (LM-80)
105
% Luminous Flux
2.155E-06
9.834E-01
L70(6k) = 158,000 hours
L70(6k) > 36,300 hours
55°C (LM-80)
100
85°C (LM-80)
95
45°C (TM-21)
90
55°C (TM-21)
85°C (TM-21)
85
61°C (LM-80)
80
75
L70: 302,000hrs
70
65
60
55
50
1,000
10,000
100,000
1,000,000
10,000,000
Time (hours)
Figure 12: XM-L TM-21 data with TSP = 61 °C
This document is provided for informational purposes only and is not a warranty or a specification. For product specifications, please see the
data sheets available at www.cree.com.
9 That is, after 35,000 hours of operation, the LED will still deliver at least 70% of its initial luminous flux.
Copyright © 2011 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree, the Cree logo and
XLamp are registered trademarks of Cree, Inc.
Copyright © 2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo and XLamp® are registered trademarks
of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact Cree Sales at [email protected]
12
XLamp xm-l 10,000-lumen High-bay Reference Design
Optical and Electrical Results
We obtained the results in Table 7 by testing the luminaire in a 2-meter sphere at steady state.10 As the table shows, the
luminaire meets the 10,000-lm target goal using less than 150 W of power and compares favorably with published data
for two comparison metal halide luminaires. The XM-L high-bay luminaire also exceeds the DesignLights Consortium
efficacy, CCT and CRI requirements.
Unit
DesignLights
Consortium High-Bay
Requirement
Comparison Metal
Halide High-Bay
Luminaire
Comparison Pulse
Start Metal Halide
High-Bay Luminaire
XM-L High-Bay
Luminaire Result
Luminous flux
lm
10,000
10,427
9,676
10,737
Power
W
-
175
150
125
Characteristic
Luminaire efficacy
lm/W
70
64
66
86
CCT
K
< 5,700 K
~ 5,000
~ 5,000
5,154
CRI
100-point scale
70
65
65
75
A
-
Current
2.3
Table 7: XM-L high-bay luminaire steady-state results
Goniometric measurements show a consistent beam shape and light distribution for the XM-L high-bay luminaire.11
8802
6602
4401
2201
Figure 13: Angular luminous intensity distribution of XM-L high-bay luminaire
The light intensity and distribution data in Table 8 show the XM-L high-bay luminaire effectively illuminates the area in
which it is installed.
10Testing was performed at Cree’s Durham Technology Center.
11Ibid.
IES files for the high-bay luminaire are available at www.cree.com/~/media/Files/Cree/LED%20Components%20and%20Modules/
XLamp/XLamp%20Reference%20Designs/Design%20files/ xml_high-bay_ies.
Copyright © 2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo and XLamp® are registered trademarks
of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact Cree Sales at [email protected]
13
XLamp xm-l 10,000-lumen High-bay Reference Design
Height
Illuminance
Diameter
1.3 m
4.2 ft
507.0 fc
5457.4 lx
1.3 m
4.3 ft
2.5 m
8.3 ft
126.8 fc
1374.3 lx
2.6 m
8.5 ft
3.8 m
12.5 ft
56.3 fc
606.3 lx
3.9 m
12.8 ft
5.7 m
16.7 ft
31.7 fc
341.0 lx
5.2 m
17.1 ft
6.3 m
20.8 ft
20.3 fc
218.3 lx
6.5 m
21.4 ft
7.6 m
25.0 ft
14.1 fc
151.6 lx
7.8 m
25.6 ft
Table 8: XM-L high-bay light intensity and distribution
Conclusions
This reference design illustrates the excellent performance of a high-bay luminaire based on the Cree XLamp XM-L LED.
The efficacy of the XM-L LED allows a relatively small number of LEDs to match the light output of comparison luminaires
with better color consistency without the metal halide’s slow start-up times and ultraviolet light. The lighting-class
performance of the Cree XLamp XM-L LED makes it an attractive design option for an LED-based high-bay luminaire.
Special thanks
Cree would like to acknowledge and thank the following partner companies that collaborated in the successful prototyping
of this luminaire.
•
Rayben
•
Steady Heat & Mass Transfer Technology Academy Ltd.
Reliance on any of the information provided in this Application Note is at the user’s sole risk. Cree and its affiliates make no warranties or representations
about, nor assume any liability with respect to, the information in this document or any LED-based lamp or luminaire made in accordance with this
reference design, including without limitation that the lamps or luminaires will not infringe the intellectual property rights of Cree or a third party.
Luminaire manufacturers who base product designs in whole or part on any Cree Application Note or Reference Design are solely responsible for the
compliance of their products with all applicable laws and industry requirements.
Copyright © 2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo and XLamp® are registered trademarks
of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact Cree Sales at [email protected]
14