"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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Halogen Lamp
A halogen lamp is an incandescent lamp with a filament that is surrounded by halogen gases, such as iodine or bromine. Halogen gases allow the filaments to be operated at higher temperatures and higher efficacies. The halogen participates in a tungsten transport cycle, returning tungsten to the filament and prolonging lamp life.

Harmonic Distortion
A measurement of the magnitude of voltage and current harmonics as compared with the amplitude of the fundamental frequency. Harmonic distortion can be generated by a load and fed back into the AC mains, causing distortion of the sinusoidal waveform.

Harmonics
Refers to components of the overall frequency, an integral multiple of the fundamental sinewave frequency.

Hertz (Hz)
Unit used to measure frequency (cycles per second) of alternating current or voltage.

High Frequency Electronic Ballast
In this book, refers to the operation of electronic ballasts as frequencies > 20,000 Hertz (20 kHz).

High-Intensity Discharge (HID) Lamp
A general term for mercury, metal halide and high-pressure sodium. HID lamps contain compact arc tubes which enclose various gases and metal salts operating at relatively high pressures and temperatures to produce light.

High Power Factor Ballast (HPF)
A ballast in which the power factor is greater than 0.9 (90%). These ballasts require less line current than normal power factor ballast.

High-Pressure Sodium (HPS) Lamp
HPS lamps are high intensity discharge light sources that product light by an electrical discharge though sodium vapor operating at relatively high pressures and temperatures.

High Reactance AutoTransformer Ballast (HX)
HID ballast used when the input voltage does not meet the starting voltage requirement for a lamp. The ballast will transform the input voltage to the required level.

High Flux
LEDs that are approximately 1.0 watts or more and provide a significantly high light intensity. Operate at 350mA.

Hot Restart Time
The time it takes a HID lamp to restart and reach 90% of its light output after going from on to off to on. Typical restart times are 1 to 2 minutes for HPS and 5 to 20 minutes for Metal Halide.

High Light Output
Ballast with a nominal ballast factor of 1.18.

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