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
| Jul 16, 2012
Business school goes for maximum vision, transparency, and safety with fire rated glass
Architects were able to create a 2-hour exit enclosure/stairwell that provided vision and maximum fire safety using fire rated glazing that seamlessly matched the look of other non-rated glazing systems.
| Jul 12, 2012
Federal budget chief to explain impact of pending defense cuts before Congress
Office of Management and Budget Director Jeffrey Zients is scheduled to testify before the House Armed Services Committee Aug. 1 to explain the possible effects of $500 billion in defense cuts on U.S. companies, including those in the design and construction industry.
| Jul 12, 2012
Pennsylvania legislature moves to prevent undocumented workers on public construction projects
Legislation to prevent undocumented workers from being hired by construction companies working on state-funded projects passed the Pennsylvania Legislature.
| Jul 12, 2012
New York’s One Bryant Park Bank of America tower is first new high-rise to achieve LEED Platinum
The new One Bryant Park Bank of America tower in midtown Manhattan is the first new commercial high-rise to achieve LEED Platinum certification.
| Jul 12, 2012
OSHA launches campaign to prevent heat illness
The Occupational Safety and Health Administration has launched its 2012 Heat Illness Prevention Campaign to educate employees and their employers about the hazards of working outdoors in heat, and how to prevent heat-related illnesses.
| Jul 12, 2012
Contractors have increasing concerns over new federal hiring quotas
A proposed rule by the U.S. Department of Labor's Office of Federal Contract Compliance Programs to increase disabled- and veteran-worker hiring quotas for federal contractors continues to raise deep concerns among contractors.
| Jul 5, 2012
Veterans Administration threatens to pull contract on new Orlando medical center
The Veterans Administration asked contractor Brasfield & Gorrie to get more workers on the job and figure out a way to get the job done faster, or the VA would pull the contract on the much-delayed Orlando VA Medical Center.
| Jul 5, 2012
Cost to contractors for new federal hiring quotas much higher than estimated, AGC says
Administration officials significantly underestimated the cost to construction employers of proposed new hiring quotas for federal contractors, according to analysis by the Associated General Contractors of America.
| Jul 5, 2012
Roof membrane could have prevented roof parking deck collapse, specialist says
The collapse of a section of a roof parking deck at the Algo Centre Mall in Elliot Lake in Ontario, Canada could have been prevented if the structure had a membrane, according to a concrete expert and specialist in structure analysis at McMaster University.
