Interior Lighting for Designers

PHOTOMETRICS Figure 10.5Illuminance on a horizontal surface— source at an angle. Figure 10.6Illuminance on a horizontal surface— ...

Source aimed at an angle to a horizontal surface If the source is aimed at an angle toward the target instead of being perpendic ...

illuminance at the target is equal to thesine of the angle of incidence or tilt. fc=× I D^2 sinθ whereIis theintensity of the so ...

For a rough estimate of the average illuminance on a horizontal surface, the abbreviated version of the lumen method described b ...

The CU also accounts for the efficiency of the room in redirecting and inter- reflecting the incident light that strikes its sur ...

office with an 8 ft ceiling and a regular arrangement of eight luminaires; each luminaire uses two 26 W compact fluores- cent la ...

illuminance values; room surface luminances; and lighting power density (watts/ft^2 ). Output is usually a chart of calculated v ...

wall coverings, ceiling tiles, floor coverings, furniture, and machinery. The followingroom reflectancesare a guide: INTERIOR LI ...

Electricity Knowledge of the basic principles of electricity is necessary for understanding lighting circuitry, electrical distr ...

resistance or interrupted by an open switch, there will be little or no current (amps) even though the potential to produce it ( ...

same circuit. Parallel circuits are therefore not load-sensitive. A current will always follow the easiest path that is availabl ...

Electrical Distribution Electric current generated and delivered by an electric utility enters a building through a service pane ...

When comparing the life cycle costs of one system with those of another, the greater ini- tial cost of an energy-effective syste ...

other; an optional center position will turn both “off.” A double-pole, single-throw switch is able to direct the current to two ...

the quantity of electric light. The control signal can activate two modes of operation: (1) a simple on-off switch or relay, or ...

A large drawback to this kind of dimmer is that the portion of the current that would otherwise produce light is instead convert ...

Square Law Dimming Curve The manner in which light output responds to changes in the control setting is called the dimming curve ...

and tungsten-halogen lamps undergo con- siderable shifts toward the orange-red end of the spectrum when they are dimmed. Althoug ...

former is connected to the luminaire. Each kind of transformer requires a compatible dimmer. Magnetic-transformerlow-voltage dim ...

start fluorescent lamps can be dimmed because voltage is supplied continuously to the cathodes. When dimmed, the special ballast ...