"The information on this website is meant to provide a general overview of the tax provisions for the interim rules of lighting systems listed in the Energy Policy Act of 2005. In all cases the services of a professional tax accountant should be retained to determine the specific tax treatment appropriate for your company. Requirements for lighting levels and controls, in accordance with EPAct 2005, must also be satisfied for eligibility. Rexel will not, in any way, accept any liability for decisions made based on the contents of this preliminary explanation."


Lighting Glossary

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PAR Lamp
PAR is an acronym for parabolic aluminized reflector. A PAR lamp, which may utilize either an incandescent filament, a halogen filament tube or a HID arc tube, is a precision pressed-glass reflector lamp. PAR lamps rely on both the internal reflector and prisms in the lens for control of the light beam.


Phosphor
An inorganic chemical compound processed into a powder and deposited on the inner glass surface of fluorescent tubes and some mercury and metal-halide lamp bulbs. Phosphors are designed to absorb short wavelength ultraviolet radiation and to transform and emit it as visible light.


Power
The amount of energy consumed or needed by a device (ballast, lamp, or ballast plus lamp) to perform its function. Power is measured in watts.


Power Factor (PF)
A measure of the phase difference between voltage and current drawn by an electrical device, such as a ballast or motor. Power factors can range from 0 to 1.0, with 1.0 being ideal. Power factor is sometimes expressed as a percent. Incandescent lamps have power factors close to 1.0 because they are simple "resistive" loads. The power factor of a fluorescent and HID lamp system is determined by the ballast used. "High" power factor usually means a rating of 0.9 or greater. Power companies may penalize users for using low power factor devices.


Preheat Circuit
A type of fluorescent lamp-ballast circuit used with the first commercial fluorescent lamp products. A push button or automatic switch is used to preheat the lamp cathodes to a glow state. Starting the lamp can then be accomplished using simple "choke" or reactor ballasts.


Probe Start
Method of starting mercury vapor and specific metal halide lamps in which an additional electrode at one end of the arc tube assists in lamp starting.


Pulse Start
Method of starting high pressure sodium and specific metal halide lamps in which a high voltage starting pulse starts the lamps.

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