A discussion on sphere theory, practical measurements and pitfalls experienced while measuring lamps and luminaires in an integrating sphere. Due to economies of scale, the acquisition of an integrating sphere is no longer confined to larger corporations. This tool is now available at reasonable cost to small companies and research facilities. Indeed, this bodes […]
Emergency lighting cycles without electrode heating before lamp ignition usually damage fluorescent lamps. Emergency lighting cycles usually damage fluorescent lamps as most emergency gear does not provide a programmed electrode heating cycle before lamp ignition or external heating during low power emergency arc discharge. These shortcomings are amplified by South Africa’s currently fragile grid, […]
A description of the process used to determine typical thermal resistance values from LED junction to case and LED junction to Ts reference point. Thermal performance is the most critical factor of a well-designed LED lighting system. A lighting system with proper thermal design has higher efficacy, meaning more light can be extracted using […]
The iconic Times Square New Year’s Eve ball, which represents a convergence of tradition and technology, has been redesigned using 9576 LEDs and triangular, double-cut crystal lenses. Each year, millions of eyes from all over the world focus on the Times Square New Year’s Eve ball, “dropped” in New York City to mark the […]
“Light Fidelity” (Li-Fi) is a new technology using visible light energy from LEDs to provide ubiquitous wireless access for communications in illuminated areas. With LiFi, data is transmitted by modulating the intensity of the light, which is then received by a photo-sensitive detector, and the light signal is demodulated into electronic form. This modulation […]
The causes of lighting overvoltages and how they affect public lighting installations Voltage surges have a very destructive impact on public lighting systems. They wear out LED drivers and distribution panels prematurely and increase service interruptions to street lighting. Beyond material damage to the luminaires, voltage surges caused by lightning, for example, can trigger […]
This article provides guidelines for LED selection, given a particular optical system. When choosing an LED for an application, its optical properties must first be considered. Properties such as lumen output, intensity distribution, and source size must be suited to the optical system of the application. Fig. 1: Example listing of flux bins. Brightness […]
Technological improvements have enabled LED floodlights to replace HID luminaires and to either achieve substantial energy savings or at least to match the power consumption of HID luminaires. High-mast lighting is found in almost all geographical locations in South Africa. It provides light to areas where either limited electrical reticulation is found or because […]
This article investigates how human nature influences our reaction to a new environment with respect to lighting. Research indicates a preference for directional or peripheral lighting as opposed to diffuse lighting, as the former provides the observer with environmental cognition while maintaining their involvement in the space. It is suggested that meeting these basic […]
The Edge is a multi-tenant office building in Amsterdam where the architect’s goal was to create an intuitive and productive environment for employees, and to inspire sustainable design around the world. Opened in 2015, The Edge received a 98,36% Building Research Establishment Environmental Assessment Methodology (BREEAM) rating, the highest rating ever. A key aspect […]
