LED Lighting 12 th Annual Building Codes Education Conference March 27-30 2017 Bozeman, MT Jaya Mukhopadhyay, Co-Director, Integrated Design Lab Montana State University, Bozeman, MT
Learning Objectives WHAT WE WILL COVER: WHAT ARE LEDS & HOW DO THEY WORK? THE COMPONENTS OF LED LIGHTING SYSTEMS OPERATIONAL CHARACTERISTICS DESIGN APPLICATIONS 4/7/2017 Integrated Design Lab, Bozeman, MT 2/31
What is a Diode? A DIODE IS A SOLID-STATE DEVICE THAT ACTS LIKE A GATE OR A SWITCH ALLOWS ELECTRONS TO FLOW IN ONLY ONE DIRECTION OFTEN USED TO CONVERT AC TO DC P-N JUNCTION (P: POSITIVE VOLTAGE, N: NEGATIVE VOLTAGE ELECTRONS IN THE N-SIDE WILL WANT TO GO TO THE P-SIDE HOLES OF THE P-SIDE WILL WANT TO GO TO THE N-SIDE 4/7/2017 Integrated Design Lab, Bozeman, MT 3/31
What is a Light Emitting Diode? LIGHT IS GENERATED BY A DIRECT CONVERSION OF ELECTRIC ENERGY INTO PHOTONS WITHIN A SOLID SEMICONDUCTOR DIE ADVANCED LIGHTING GUIDELINES PHOTONS THAT ESCAPE THE CHIP PRODUCE VISIBLE LIGHT, OTHERS ARE REABSORBED THE LIGHT PRODUCED IS HIGHLY DIRECTIONAL & FREQUENCY (COLOR) SPECIFIC LEDS HAVE A MAXIMUM DRIVE CURRENT LEDS HAVE A MAXIMUM CHIP JUNCTION TEMPERATURE (TJ) 4/7/2017 Integrated Design Lab, Bozeman, MT 4/31
How Does a LED Work? TO TURN ON AN LED: FORWARD VOLTAGE (VF) APPLIED TO ANODE LEAD (KNOWN AS FORWARD BIASING THE LED ) LIGHT OUTPUT INCREASES WITH INCREASED FORWARD CURRENT THROUGH THE LED THE RATED CURRENT IS A FUNCTION OF CHIP SIZE & DESIGN FEW COMPANIES MANUFACTURE THE BASIC LED CHIPS https://en.wikipedia.org/wiki/light-emitting_diode LEDS HAVE NO GAS, NO FILAMENT, NO GLASS BULB, NO MOVING PARTS THAT MIGHT FAIL 4/7/2017 Integrated Design Lab, Bozeman, MT 5/31
What are the Types of LEDs? MINIATURE LEDS INDICATOR LAMPS, SIZES 2 MM TO 8 MM, THROUGH-HOLE OR SURFACE MOUNT MID-RANGE LEDS FEW LUMEN OUTPUT FOR LIGHT PANELS, EXIT SIGNS, CAR TAIL-LIGHTS HIGH-POWER LEDS FOR ARCHITECTURAL LIGHTING POWER DENSITIES UP TO 300W/CM 2, MUST HAVE A HEAT SINK EXAMPLES: NICHIA 19, LUMILEDS REBEL, OSRAM 4/7/2017 Integrated Design Lab, Bozeman, MT 6/31
What are the Components of a High-Power LED Package? AN LED PACKAGE CONSISTS OF: AN LED CHIP OR DIE SUBSTRATE: SLUG OF COPPER, CERAMIC OR ALUMINUM MOST COMMON: ACTS AS A THERMAL PATHWAY ENCAPSULANT: CLEAR COVERING THAT PROTECTS THE CHIP & BOND WIRES: USUALLY SOFT SILICON GEL OR HARD EPOXY LENS (OPTIONAL): TO INCREASE OUTPUT EFFICIENCY OR CHANGE DISTRIBUTION LEADS: ELECTRICAL CONNECTIONS, EITHER A LEADED LED PACKAGE TO INSERT IN A CIRCUIT BOARD OR A SURFACE MOUNT WITH SOLDERED CONNECTIONS ONTO PRINTED PADS 4/7/2017 Integrated Design Lab, Bozeman, MT 7/31
Advantages of LEDs EFFICACY (LUMENS/WATT): SIMILAR TO FLUORESCENT DIRECTIONAL SOURCE: EFFICIENT OPTICS POSSIBLE CCT & CRI IMPROVEMENTS, COMPARABLE TO CFL LAMPS VERY LONG USEFUL LIFE NO MERCURY OR LEAD NO INFRARED OR ULTRAVIOLET COLD OPERATION RESISTANT TO IMPACT & VIBRATION INSTANT ON, DIGITAL CONTROL POSSIBLE 4/7/2017 Integrated Design Lab, Bozeman, MT 8/31 https://www.energy.gov/eere/ssl/led-basics
How Do LEDs Produce Color? COLOR IS DETERMINED BY CHIP COMPOSITION EACH CHIP PRODUCES PHOTONS OF A UNIQUE COLOR SLIGHT VARIATIONS IN CHIPS LEAD TO COLOR VARIATIONS HIGH-BRIGHTNESS RED, AMBER: ALLN-GAP CHIPS HIGH-BRIGHTNESS BLUE, GREEN, CYAN: INGAN CHIPS GAP IN YELLOW-GREEN REGION FILLED BY DIFFERENT COLORS IN SAME DEVICE PRODUCING A QUALITY WHITE LIGHT HAS BEEN A CHALLENGE 4/7/2017 Integrated Design Lab, Bozeman, MT 9/31
Colors of LED Lamps COURTESY OF LUXEON 4/7/2017 Integrated Design Lab, Bozeman, MT 10/31
White LEDs THREE METHODS FOR CREATING WHITE LEDS: SINGLE COLOR WHITE LEDS (SINGLE LAMP) MULTIPLE-COLOR WHITE LEDS (RGB MIXING OF MULTIPLE LAMPS) HYBRID METHOD 4/7/2017 Integrated Design Lab, Bozeman, MT 11/31 https://www.energy.gov/eere/ssl/led-basics
Single Lamp White LEDs BLUE LED PLUS PHOSPHOR: SPECTRUM: BLUE SPIKE WITH GREEN, YELLOW, RED PORTIONS EARLY LEDS: BLUISH WHITE, UNEVEN COLOR IN THE BEAM NEW ADVANCES IN PHOSPHORS: RED ENHANCED WARM WHITE LED WITH CCT DOWN TO 2700K NEW TECHNOLOGY: GAN ON GAN CHIPS (SORAA COMPANY) HIGH LIGHT OUTPUT, HIGH CRI (DEEP RED COLOR RENDERING) GOOD ALTERNATIVE TO MR16 HALOGENS 2700K OR 3000K, CRI UP TO 95 4/7/2017 Integrated Design Lab, Bozeman, MT 12/31
Multiple Color White LEDs RGB (RED, GREEN, BLUE) COLOR MIXING: LEDS DIMMED TO DIFFERENT LEVELS TO CREATE PARTICULAR COLOR USE WHERE COLORED LIGHT IS DESIRABLE HYBRID WHITE: WHITE LED PLUS RED LED TO LOWER THE CCT TENDS TO BE EXPENSIVE PASTELS MAY LOOK UNNATURAL 4/7/2017 Integrated Design Lab, Bozeman, MT 13/31
LED Color Binning SLIGHT VARIATIONS IN MANUFACTURING CREATES COLOR VARIATIONS: EACH CHIP TESTED FOR VOLTAGE RATING, COLOR, & LUMEN OUTPUT SORTED INTO BINS BY RANGE OF PERFORMANCE VALUES BINS RESPOND TO MACADAM ELLIPSE: RANGE OF COLOR DIFFERENCES THAT ARE PERCEPTIBLE SINGLE COLOR LEDS SORTED BY DOMINANT WAVELENGTH PHOSPHOR WHITE LEDS: USES CIE COLOR COORDINATE RANGES NEMA STANDARD SSL 3-2011 SETS BINS FOR CHROMATICITY, FORWARD VOLTAGE, LUMINOUS FLUX FOR LEDS USED IN GENERAL LIGHTING 4/7/2017 Integrated Design Lab, Bozeman, MT 14/31
LED Color Binning MACADAMS ELLIPSE 4/7/2017 Integrated Design Lab, Bozeman, MT 15/31 https://www.ecse.rpi.edu/~schubert/light-emitting-diodes-dot-org/chap17/chap17.htm
Electronic Power Control POWER SUPPLY: LED DRIVER: CONVERTS INCOMING AC VOLTAGE TO A USUALLY LOWER DC VOLTAGE REGULATES & LIMITS THE LED CURRENT MAY BE COMBINED WITH POWER SUPPLY SIMILAR TO A BALLAST IN A FLUORESCENT SYSTEM TOGETHER THESE COMPONENTS SUPPLY & REGULATE POWER TO THE LED ARRAY CONTROLLER: SWITCH, DIM, OR ALLOW COLOR MIXING IN THE SYSTEM 4/7/2017 Integrated Design Lab, Bozeman, MT 16/31
How Does Heat Affect LEDs? CURRENT THROUGH THE JUNCTION CREATES HEAT CAN DAMAGE LED IF HEAT EXCEEDS MAXIMUM TJ LEDS EMPLOY A HEAT SINK NEAR THE CHIP JUNCTION HEAT MUST FLOW EASILY FROM HEAT SINK TO THE ENVIRONMENT LIGHT OUTPUT DECREASES WITH INCREASING JUNCTION TEMPERATURE THIS HEAT EFFECT ON LIGHT OUTPUT IS REVERSIBLE 4/7/2017 Integrated Design Lab, Bozeman, MT 17/31
Useful Life of LED Lamps CONVENTIONAL LAMPS RATED LIFE: RATED LIFE AT 50% LAMP FAILURE POINT LED LAMPS USEFUL LIFE: BASED ON LUMEN MAINTENANCE & DEPRECIATION STANDARD: IES LM-80 USES LP MAINTENANCE MEASUREMENT WHERE: L IS INITIAL OUTPUT P IS PERCENTAGE MAINTAINED OVER A NUMBER OF HOURS EXAMPLE: L70 / 60,000 WHERE 70% OF INITIAL OUTPUT (30% LOSS) REACHED IN 60,000 HOURS 4/7/2017 Integrated Design Lab, Bozeman, MT 18/31
Light Output for LEDs SPECTRAL DISTRIBUTION POWER WEB: http://www.gelighting.com/lightingweb/na/resources/tools/lampand-ballast/spectral-power-distribution-curves.jsp Tri-phosphor linear fluorescent Daylight Incandescent 93 CRI LED Lamp Phosphor LED Lamp Tri-Color LED Lamp
LED Replacement Lamps CURRENT LED REPLACEMENT TARGETS: INCANDESCENT/HALOGEN SCREW BASE FLUORESCENT T12 & T8, 4 FOOT LAMPS Courtesy of SATCO Courtesy of Lighting Design Lab 4/7/2017 Integrated Design Lab, Bozeman, MT 20/31
LED Incandescent Replacements OMNIDIRECTIONAL INCANDESCENT LAMPS: TARGET: GENERAL SERVICE INCANDESCENT LAMPS SHAPES: A, BT, P, PS, S, & T RECENT IMPROVEMENTS IN LIGHT OUTPUT & EFFICACY: SOME NOW SURPASSING CFL PERFORMANCE DIRECTIONAL INCANDESCENT LAMPS: SHAPES: BR, ER, K, MR16, PAR16/20/30/38 DISTRIBUTION: SPOT, FLOOD, WIDE FLOOD DOE CALIPER TESTING: LED PAR30 & PAR38 EXCEED HALOGEN IN LIGHT OUTPUT & EFFICACY WITH IMPROVED CBCP Courtesy of GE 4/7/2017 Integrated Design Lab, Bozeman, MT 21/31
LED MR16 Replacements Courtesy of GE & SORAA 4/7/2017 Integrated Design Lab, Bozeman, MT 22/31
LED Fluorescent Replacements LINEAR FLUORESCENT REPLACEMENT LAMPS: TARGET: 4 FOOT T8 & T12 IN EXISTING TROFFERS ADVANTAGES: ENERGY SAVINGS: 2-18W ABOUT 40% (CHECK LIGHT OUTPUT) MAINTENANCE SAVINGS: FEW SPOT REPLACEMENTS OVER LIFE NO MERCURY OR LEAD COLD STARTING (WHICH MAY IMPROVE LIFE) SHOCK & VIBRATION RESISTANT DISADVANTAGES: POOR LIGHT OUTPUT: MAY NEED TO ADD LAMPS TO MAINTAIN LEVELS STRONG DIRECTIONALITY: POOR UNIFORMITY COST OF BYPASSING BALLAST (OR REDUCED EFFICACY IF USING THE BALLAST) SOME FLUORESCENT LAMPS RATED AT 55,000 HOURS SO MAINTENANCE BENEFIT MAY NOT EXIST 4/7/2017 Integrated Design Lab, Bozeman, MT 23/31
LED Applications Courtesy of PHILIPS LEDALITE 4/7/2017 Integrated Design Lab, Bozeman, MT 24/31
LED Applications Courtesy of PHILIPS LUMIBLADE 4/7/2017 Integrated Design Lab, Bozeman, MT 25/31
LED Applications Courtesy of INTENSE LIGHTING 4/7/2017 Integrated Design Lab, Bozeman, MT 26/31
LED Applications Courtesy of YARNELL ASSOC. 4/7/2017 Integrated Design Lab, Bozeman, MT 27/31
LED Applications Courtesy of YARNELL ASSOC. 4/7/2017 Integrated Design Lab, Bozeman, MT 28/31
LED Applications Courtesy of GE 4/7/2017 Integrated Design Lab, Bozeman, MT 29/31
Resources Laboratories: Lighting Design Lab, Seattle www.lightingdesignlab.com Lighting Research Center www.lrc.rpi.edu Government: Energy Star www.energystar.gov Energy Efficiency & Renewable Energy www.eere.energy.gov/buildings Magazine: Architectural Solid State Lighting www.architecturalssl.com 4/7/2017 Integrated Design Lab, Bozeman, MT 30/31
Jaya Mukhopadhyay Assistant Professor School of Architecture Integrated Design Lab Montana State University Bozeman, Montana 59717 E Mail: jaya.mukhopadhyay@montana.edu wood@montana.edu Phone: 406-994-6439 (office) or 406-994-4934 (lab) Web: www.idlbozeman.com