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
| Nov 18, 2011
New OSHA fall safety rule could save contractors money on insurance premiums
The new Occupational Safety and Health Administration rule requiring employers operating in the residential construction industry to use the same methods of fall protection that historically have been used in the commercial construction industry could save them money.
| Nov 18, 2011
Some believe new Austin building code will help mom and pop shops
Austin, Texas has proposed building codes that require wider sidewalks and call for buildings to be closer to sidewalks along a 3.5-mile stretch of highway.
| Nov 11, 2011
AIA: Engineered Brick + Masonry for Commercial Buildings
Earn 1.0 AIA/CES learning units by studying this article and successfully completing the online exam.
| Nov 10, 2011
WaterSense standard for weather-based irrigation controllers unveiled
The U.S. Environmental Protection Agency’s (EPA) WaterSense program has released a final specification for weather-based irrigation controllers—the first outdoor product category eligible to earn the WaterSense label.
| Nov 10, 2011
Advocate seeks noise reduction measures in California building codes
A former chief building inspector for San Francisco wants to enact building codes that would limit noise levels in restaurants and other spaces open to the public.
| Nov 10, 2011
California seismic codes spur flurry of hospital projects
New seismic requirements in California are helping to drive a flurry of new projects and retrofits in the state’s health care sector.
| Nov 10, 2011
Senate ready to repeal 3% withholding on government contracts
The U.S. Senate is set to approve legislation that would eliminate a law requiring federal, state, and local governments to withhold 3% of their payments to contractors and companies doing business with the government.
| Nov 10, 2011
New legislation aimed at improving energy efficiency in federal buildings
Recently introduced legislation, the “High-Performance Federal Buildings Act,” would help federal agencies save energy and money by improving building performance.
| Nov 4, 2011
CSI and ICC Evaluation Service agree to reference GreenFormat in ICC-ES Environmental Reports?
ICC-ES currently references CSI's MasterFormat and other formats in all of its evaluation reports. The MOU will add GreenFormat references.
| Nov 3, 2011
House Votes to Kill 3% Withholding Requirement; Senate Yet to Vote
The U.S. House of Representatives voted last week to repeal a 3% IRS withholding tax on businesses that do work for the government.
