The Gamma Scientific Laboratory, NVLAP Lab Code 200823-0, has been awarded accreditation by the National Voluntary Laboratory Accreditation Program (NVLAP) under the Energy Efficient Lighting Products Program.
This accreditation includes IES LM-80:2008 for Solid State Lighting Luminaires-Lumen Maintenance (SSL Life Tests), and we have an EPA Recognized Laboratory for Lighting Products.
In addition to LM80 testing, Gamma Scientific is accredited to provide LM-79 testing for Solid State Lighting Luminaires – Total Flux Measurements (Luminous Efficacy) and Solid State Lighting Luminaires –Luminous Intensity Measurements.
What is LM-80?
IES LM-80-08 is an approved method for measuring lumen depreciation and maintenance of Solid State Lighting (LED) light sources, arrays and modules. The Illuminating Engineering Society (IES) developed the standard to provide an objective method to evaluate and compare LED components from different manufacturers.
It is important to understand that LM-80 is an approved method for testing LED components, and does not cover the measurement of luminaires. LM-80 reports document how LED components perform over a set period of time under specific conditions, and are not a measure of reliability. The standard also does not define or provide methods for estimation of expected life or lumen output beyond the test data.
LED Lifetime and Lumen Maintenance
Life testing for LEDs is different than conventional light sources because LEDs do not typically fail. Other light sources (incandescent, fluorescent, etc.) usually burn out before they begin to lose light output. However, since LEDs do not have a filament to burn out, the light output for an LED will degrade over time until it is no longer useful.
Lumen maintenance is the percentage of initial lumens that a light source maintains over a defined period of time. LM-80 measures the depreciation of lumens over a specific timeframe to determine the useful life of LED components. Life tests for other more traditional light sources measure rated lamp life, which is typically set at a 50% failure rate since these sources burn out.
LM-80 Measurement Methods
- Case Temperatures
- Measurement performed at multiple temperatures to address in-situ conditions
- 55°C, 85°C and 3rd manufacturer selected temperature
- Spectral radiometer preferred method
- Temperature: 25°C ambient
- Drive current per manufacturer
- Testing Intervals
- 6,000 hours minimum testing periods; 10,000 hours preferred
- Minimum at least every 1,000 hours
- Ambient conditions and setup
- Case temperature measured and maintained
- Case temperature measurement point
- Airflow minimized
- Operating orientation and spacing per manufacturer
- Voltage and Current (AC or DC levels)
- Voltage waveshape (harmonic distortion < 3%)
- Current regulation
LM-80 Test Reports
- Description of sources tested
- Ambient conditions (Airflow, temp, RH, etc.)
- Case Test point temperature
- Electrical conditions
- Lumen maintenance date
- Observation of failures
- LED monitoring interval
- Chromaticity shift over time