Understanding the reliability of LED luminaires

Abstract

The purpose of this paper is to educate both manufacturers and end users on what constitutes the overall reliability of an LED luminaire and the reliabilities of individual subsystems. Wide ranges of LED luminaires are available in the market to meet the needs of a specific applications, hence a potentially wide range of product performance characteristics exist. The different subsystems in an LED luminaire introduce other potential reliability issues that will be critical in deciding the overall system lifetime. The mutual dependency of subsystems and their interactions make the prospect of characterizing LED luminaire reliability challenging. Best design practices ensure that the overall luminaire reliability will be decided by a small number of subsystems, thus reducing the complexity. In this paper, a general theory of assessing the reliability of the optical, electrical and thermal subsystems of an LED luminaire is discussed. How the remaining useful lives of the subsystems are obtained from their degradation profile and how the remaining useful life of the entire system is derived from them are explained. The theory explained in this paper is useful in designing experiments to express the reliability of an LED luminaire and its subsystems in terms of remaining useful life.

Endurance Test on Photometric Performance for First Generation Led Luminaires

“…The collected measured data can then be used for lifetime projections. Standard models (IES 2011) and experimental models (Wagner et al, 2017, Shailesh et al, 2018 exist, but predictions vary with the method used for extrapolating the accelerated test data. It is often stipulated that any projection may not exceed a pre-set multiple of the actual tested hours.…”

Quantitative Assessment of Architectural Lighting Designs

“…After the war the ruins of this building became an important memorial called the Tomb of the Unknown Soldier in Warsaw. This object is still being illuminated using up-to-date luminaires with high-efficiency electroluminescent light sources [7][8][9][10][11][12].…”

Tackling Heterogeneous Color Registration: Binning Color Sensors

“…Intelligent systems for interior lighting are conceived to automatically find the optimal balance between energy consumption, legal requirements, visual performance, user comfort, and health considerations [ 1 ]. A closed-loop feedback design with input from optical sensors seems to be most expedient and has already been adopted successfully in practical research [ 2 , 3 , 4 , 5 , 6 , 7 , 8 ] in order to ensure that such systems are capable of monitoring and dynamically adapting to continuous changes in the environmental conditions and the lighting parameters, e.g., caused by variations of the natural daylight entry through windows and skylights [ 9 , 10 , 11 ] or by degradation and temperature processes in the luminaires [ 12 , 13 , 14 ].…”