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
| Oct 28, 2011
Los Angeles County mulling building codes for improving health
An ordinance would amend county building codes to promote better walking environments, encourage more bicycling, improve access to healthy foods (farmers markets, community gardens), and enhance project review requirements to ensure that developers include healthy-lifestyle components in their building plans.
| Oct 28, 2011
Bipartisan opposition to federal 3% withholding for contractors
Both major political parties and the Obama Administration support repealing a law that would withhold 3% of all government contracts.
| Oct 28, 2011
OSHA requires training module on top causes of construction deaths
The Occupational Health and Safety Administration (OSHA) now requires a training module on the top four causes of death for construction workers.
| Oct 28, 2011
New York City requiring building energy use to be posted online
Owners of every New York City commercial and residential building larger than 50,000 sf will have to post each building’s energy use online by 2013.
| Oct 28, 2011
New ISO standard for escalator safety
A new ISO standard specifies safety requirements for escalators and moving walks.
| Oct 20, 2011
LEED 2012 to require real-time energy, water use reporting
The LEED 2012 rating system, set to launch in November 2012, will contain features to make sure buildings function as intended, and improve over time.
| Oct 20, 2011
New York City moving to speedier, online design reviews
New York City is moving towards a development design review process that will let officials and developers review blueprints for new projects online in a virtual conference room rather than in person.
| Oct 20, 2011
Michigan bill would let private firms operate as a city’s building department
Michigan House Bill 5011 would change state’s building code to allow private companies to operate as a municipality's building department.
| Oct 20, 2011
Alabama’s strict immigration law drives away construction workers
Alabama's strict new immigration law is driving many construction workers and roofers from the state.
| Oct 20, 2011
Fed bill would allow school rehab funding via historic tax credits
Virginia Sens. Jim Webb (D) and Mark Warner (D) introduced a bill this month to rehab aging schools across the country through the use of historic tax credits.
