The U.S. Department of Energy recently released a report on the initial performance and reliability of chromaticity sensors used for tunable LED lighting systems.
This study found that a chromaticity sensor used in the control system of a tunable lighting installation has high reliability, even under relatively harsh test conditions. The study examined the initial performance and aging characteristics of a sensor consisting of a series of six photodiodes that respond to different wavelengths to adjust illuminance, correlated color temperature (CCT), and chromaticity.
The sensor devices were exposed to a 5,000-hour accelerated stress test: one group at a continuous room temperature operating life, a second at a continuous but elevated ambient temperature of 75°C, and a third in a temperature-humidity environment of 75°C and 75% relative humidity (also known as a 7575 environment).
No abrupt failure of the sensor was found after 5,000 hours of testing, even in the relatively harsh 7575 environment. Just one parametric failure after 5,000 hours of 7575 testing was observed. Such a failure produces a change in a tunable device that would be noticeable to an observer. Light from the tunable fixture would likely be blue-shifted.
Related Stories
| Jun 5, 2014
Over budget Homeland Security headquarters project may be canceled
A massive new headquarters for the Department of Homeland Security is more than $1.5 billion over budget, 11 years behind schedule, and may never be completed.
| Jun 5, 2014
Insurance giant sues nearly 200 Illinois communities for failing to prepare for climate change
Farmers Insurance filed nine class action suits against nearly 200 communities in the Chicago area, saying that local governments should have prepared for rising global temperatures that have led to heavier rains and flooding.
| Jun 4, 2014
Dikes, water pumps, and parks will help New York City area be more resilient
The Obama Administration has pledged $1 billion in federal funding to protect the New York City region from flooding like the area experienced from Superstorm Sandy.
| Jun 4, 2014
Green initiative may scuttle high-rise projects in Berkeley, California, critics charge
Volunteers in Berkeley, Calif., are collecting signatures for the “Green Downtown & Public Commons Initiative,” a controversial measure that critics charge would halt some development in the city.
| Jun 2, 2014
Parking structures group launches LEED-type program for parking garages
The Green Parking Council, an affiliate of the International Parking Institute, has launched the Green Garage Certification program, the parking industry equivalent of LEED certification.
| May 28, 2014
Commercial building measurement standard could meet resistance from owners
For some building owners, a new measurement standard could mean that their building would shrink in size and lose value.
| May 28, 2014
Resiliency measures for hurricanes can help with tornadoes
Architect Butch Grimes, who examined the wreckage after a half-mile tornado struck Tuscaloosa, Ala., believes toughening building codes can reduce damage from twisters.
| May 28, 2014
Rooftop wind turbines becoming green status symbol in New York City
New York City developers are using rooftop wind turbines in an effort to attract buyers by highlighting a building’s green credentials.
| May 28, 2014
Peer review process under way for the WELL Building Standard
The standard is the first protocol of its kind that focuses on improving human wellness within the built environment by identifying specific conditions that, when holistically integrated into building interiors, enhance the health and wellbeing of the occupants.
| May 22, 2014
ASHRAE releases best practice guide for liquid cooling systems in data centers
The publication provides guidelines on interface requirements between chilled-water systems and technology cooling systems and on the requirements of liquid-cooled systems that attach to a datacom electronics rack.
