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
| May 27, 2013
Bill would mandate contractors use subs identified in bids on federal projects
Rep. Carolyn Maloney (D-N.Y.) filed a bill in May that would require prime contractors that bid on federal construction projects over $1 million to list each subcontractor they plan to use for $100,000 or more of work.
| May 27, 2013
Maryland law on codes for wind resistance will take effect in October
The Insurance Institute for Business & Home Safety says that Maryland citizens will be safer due to legislation passed by the legislature and signed into law by Gov. Martin O’Malley.
| May 23, 2013
AGC Contractors Environmental Conference focuses on compliance issues
The 2013 AGC Contractors Environmental Conference June 13 and 14 in Arlington, Va., will include cost-effective strategies for firms to remain compliant and competitive.
| May 23, 2013
ASTM releases new carbon steel hollow structural sections
ASTM has released a new HSS standard, A1085 - 13 Standard Specification for Cold-Formed Welded Carbon Steel Hollow Structural Sections (HSS).
| May 23, 2013
Group Health Puyallup medical center first project to achieve 'LEED for Health Care' certification
The Group Health Puyallup (Wash.) Medical Center is the first facility to be certified under the LEED for Healthcare (LEED-HC) rating system, earning LEED Gold.
| May 17, 2013
LEED v4 has provision to reduce water use in cooling towers
The next version of the U.S. Green Building Council's LEED rating system will expand water-savings targets to appliances, cooling towers, commercial kitchen equipment, and other areas.
| May 15, 2013
New York City Council okays plans for Cornell's huge net-zero tech campus
Cornell University's proposal to build a two million sf tech campus on Roosevelt Island has been approved by the New York City Council.
| May 15, 2013
Center for Green Schools, Architecture for Humanity release new tool for green schools
The 70-page guide demystifies the processes of identifying building improvement opportunities and finance and implementation strategies.
| May 15, 2013
AAMA extends NAFS certification on fenestration products
The American Architectural Manufacturers Association (AAMA) announced the release of an interim procedural guide that will provide a documented, optional process to extend current, unexpired AAMA product certification to any edition of AAMA/WDMA(/CSA) 101/I.S.2(/A440), North American Fenestration Standard/Specification for windows, doors, and skylights (NAFS).
| May 9, 2013
New developments would face tougher stormwater rules than redeveloped sites under EPA proposal
New developments would have to meet more stringent stormwater-retention standards than redeveloped sites under a forthcoming Environmental Protection Agency proposal.
