Assessments of LEDs IESNA LM-79, LM-80 & LM-82 by Rolf S. Bergman Consultant 4/30/2012 1 ALA M
Outline of Presentation Background Information EPA Energy Star specifications NVLAP Accreditation IESNA Technical Procedures 4/30/2012 2 ALA M
IESNA SSL Procedures IESNA LM-79-08 Electrical and Photometric Measurements of Solid-State Lighting Products IESNA LM-80-08 Measuring Lumen Maintenance of LED Light Sources IESNA TM-21-11 Projecting Long Term Lumen Maintenance of LED Light Sources IESNA LM-82-12 Characterization of LED Light Engines and LED Lamps for Electrical and Photometric Properties as a Function of Temperature 4/30/2012 3 ALA M
LM-79 Assessment Scope Covers Luminaires and Integrated Lamps Electrical Performance Color Performance Photometric Performance Luminous Flux (integrating sphere, either 2 or 4 geometry) Luminous Intensity (goniophotometer) Under revision, new edition in about a year 4/30/2012 4
LM-79 Integrating Sphere: Spectral data Integrating sphere shall have a broadband auxiliary lamp for self-absorption measurement 4 geometry mounted in center of sphere total spectral radiant flux standard lamp 2 geometry mounted on flush on the sphere wall total spectral radiant flux standard lamp with only forward distribution (required) ambient temperature in sphere 25 C ± 1 C input optic flat diffuser or a satellite sphere 4/30/2012 5
LM-79 Integrating Sphere: photometer Integrating sphere shall have an auxiliary lamp for selfabsorption measurement (similar spectrum) 4π geometry mounted in center of sphere 2 π geometry mounted on flush on the sphere wall total luminous flux standard lamp (spatial corrections) ambient temperature in sphere 25 C ± 1 C detector cosine response with well matched to V(λ) function including sphere spectral throughput 4/30/2012 6
Type C only LM-79 Goniometer Spatial scanning resolution fine enough to accurately define the test sample shall be used. The range of the angular scan shall cover the entire solid angle to which the SSL product emits light. The f 1 of the detector shall be less than 3 %. Detector shall be calibrated against an illuminance or luminous intensity standard traceable to national standards. 4/30/2012 7
LM-80 Assessment Scope Covers devices, modules or arrays Electrical Performance Photometric Performance according to LM-79 Every 1000 hours Spectral flux to obtain color shifts Luminous Flux (integrating sphere) Luminous Intensity (goniophotometer) Maintenance Performance 6000 hrs 4/30/2012 8
LM-82 Assessment Scope Covers LED Light Engines and Integrated Lamps Characterizes the unit under test (UUT) as a function of temperature 1. First test using LM-79 procedure (sphere or goniometer) at room temperature (25 1 C) 2. Next test with a temperature-control device to get same Temperature as measured in 1. 3. Finally measure at a temperature 25 C above that in 2. Provide data on shifts in electrical, photometric and color parameters 4/30/2012 9
Report all Assessment factors Accommodation/Environment Equipment / Reference Manuals Calibration Tests Method Procedures incorporated Handling / Preparation of Test Items Test reports Other factors 4/30/2012 10
LM-79 Current Issues needs revision to address a number of issues Power control vs. line voltage variation Power factor specification color measurement capability for goniophotometers LM-80 requires testing times (6000 hrs) that are too long for industry does not address life or maintenance of luminaires requires spectral photometry at test intervals 4/30/2012 11