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
| Sep 11, 2013
Sports stadium accidents suggest code updates may be necessary to prevent falls
Since 2000, at least three individuals have died as a result of falling from the upper decks of stadiums in the United States. In addition, eight non-fatal falls have occurred in stadiums and arenas over that time.
| Sep 11, 2013
White paper examines Joint Commission requirements for NFPA codes in healthcare
The healthcare industry has experienced great attention from The Joint Commission concerning fire and life safety issues.
| Sep 11, 2013
San Francisco expected to drop firefighter air tank refilling station rule for skyscrapers
San Francisco is poised to drop a requirement that skyscrapers have refill stations so firefighters can recharge their air tanks during a blaze. The city has required that new high-rises have the air refill systems for about ten years.
| Sep 5, 2013
State legislatures continue to raise the bar on green school construction
Since the beginning of 2013, the USGBC has followed more than 125 bills across 34 states that seek to advance healthy, high-performing schools.
| Sep 5, 2013
Construction industry groups create coalition to respond to new OSHA silica rule
A group of 11 construction trade associations has created the Construction Industry Safety Coalition in response to the Occupational Safety and Health Administration’s (OSHA) proposed rule on silica for the construction industry.
| Sep 5, 2013
Red tape delays California county jail construction projects
California authorized $1.2 billion for jail construction in 2007, but not a single county in the state has completed a jail project since then.
| Sep 5, 2013
New CM-at-risk and design-build options create controversy in Ohio
Some contractors say Ohio's new system puts small and midsize construction companies at a disadvantage.
| Sep 5, 2013
Outdated codes slowed disaster recovery in Tuscaloosa, Ala.
Outdated building codes and lack of a master plan slowed the initial rebuilding stage after a devastating tornado leveled parts of Tuscaloosa, Ala. in 2011, according to the city’s mayor.
| Aug 28, 2013
Building collapse prompts legislation to beef up demolition regulations in Philadelphia
Philadelphia City Council will introduce legislation next month to strengthen the regulation of building demolition practices.
| Aug 28, 2013
Rules requiring contractors to boost hiring of veterans criticized
Some businesses are pushing back against proposed rules requiring federal contractors to step up their hiring of returning military service personnel.
