IEEE Std 1789 pdf free download

IEEE Std 1789 pdf free download.Modulating Current in High-Brightness LEDs for Mitigating Health Risks to Viewers.
These projected energy savings are based on assumptions about the adoption of this new technology; if these assumptions arc not met, the savings will not occur. The path to adoption of any new technology should take into account lessons learned from the introduction of previous technologies, in the case of LED lighting, the comparator case is the introduction of compact fluorescent lamps (CFLs) in the early- to mid- 1 990s. It is widely accepted that the uptake of CFLs was much slower than had been anticipated, and the projected energy savings did not materialize (Sandahi Ct al. [B94]). Equipment performance was among the problems that hindered adoption, and one of the key lessons derived from the CFL experience was Don’t launch a product until performance issues are ironed out” (Sandahi et at. [B94]).
Among the performance issues that contributed to slow CFL uptake was the perception that fluorescent lighting can cause adverse health effects. Flicker had long been among the complaints made about fluorescent lighting (Stone [B 103]), when Beckstead and Boyce [B4j found that the belief that fluorescent lighting could cause negative effects on people predicted the likelihood that people would use fluorescent lighting at home. As the lighting industry strives not to repeat the CFL experience, these findings underpin the need for recommended practices concerning LED flicker.
Other clauses of this document summarize what is known concerning the effects of flicker on human health and well-being (see Clause 6) and the variety of flicker rates that LED lighting systems can exhibit (see Clause 5). Possible adverse health effects can occur under flicker conditions that lie outside the visible range (see Clause 7); the nervous system can detect and respond to these conditions without their being accessible to conscious reports of the perception. This sets the stage for learned associations between LED lighting and potential adverse health effects from the specific product to the general class of’ LED products.
Given the wide variety of flicker patterns detected in LED products already on the market (Poplawski Ct al. [B84]), some of which may lie in the region where potential health risks exist, it is possible that the public will associate this new technology with negative health outcomes. However, the lighting industry has the opportunity through product design to reduce the occurrence of flicker conditions that could cause potential adverse health and well-being effects and thereby help avoid a future in which the public associates LEDs with these outcomes. A recommended practice for LED lighting flicker can make a valuable contribution to the speedy adoption of LED technology and the achievement of energy efficiency targets by defining, based on science and consensus, the flicker conditions that may best be avoided.
Prior to the IEEE P1789 Working Group, there were no formal entities that were allowing designers, health experts, and engineers to discuss the best guidelines flicker in SSL. This vacuum left engineers to design their power electronic drivers without knowledge of possible health effects to the public. The scope of this document is to
Define the concept of modulation frequencies for LEDs and give discussion on their applications to
LED lighting.
Describe LED lighting applications in which modulation frequencies pose possible health risks to
users.
— Discuss the concept of dimming of LEDs by modulating the frequency of dnving currents/voltage.
— Present recommendations and design guidelines that can help enable a designer to select, with more knowledge. appropriate power electronic drivers to desirably modulate frequencies for LED lighting and dimming applications to help protect against possible adverse health effects.
IEEE Std 1789 pdf download.