BU3 Lighting

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Low Pressure Sodium (LPS)

Low pressure sodium lamps produce a monochromatic yellow- wavelength light at 589 nm. The lamp is filled with sodium vapor and small amounts of argon, xenon or helium as starting gas. LPS is not suitable for interior lighting applications in buildings. The principal applications of LPS lamps are highway exchanges, storage yards, etc. and whenever color-rendition is unimportant or a strong dominant color (yellow) is desired.

Luminous Efficacy

Luminous efficacy or, simply, efficacy is defined as the light output per unit of electrical power (watts) input or lumen/watt (lm/w)

Lead-in Wires

Made from base to stem press and nickel from press to filament; carries current to filament.

Preheat lamp

Manual or automatic starter switch is require for this type of lamp. These are limited to small wattages. Lamps 30 watts or higher are not normally used in building systems.

Mercury lamps

Mercury lamps contain mercury vapor and produces bluish white light. These type of lamps are generally used for industrial and outdoor application.

Metal Halide (MH) Lamps

Metal halide lamps contain mercury vapor and other halides to improve both thei efficacy and their color-rendering characteristics. Typical halides used are scandium, sodium oxides. dysprosium, indium oxide and other rare earth iodides. These lamps are mostly applicable to indoor use.

Support Wires

Molybdemun wires support the filament

Low Pressure Sodium (LPS) Lamps

Monochromatic lamps in the yellow region of the spectrum. Typical applications are along highways and in storage yards.

Short-arc Lamps or Compact Arc lamps

Of the xenon family of lamps, produce light in a small tube and are the closest thing to a true point source of high luminance. Used for search lights, projectors or optical instruments.

PL Lamps

PL Lamps are single-ended fluorescent lamps. They are available from a few watts up to 18 watts. Duo to their compact size, they are popular for illuminating general spaces that previously were lit by incandescent lamps. PL Lamps may last as long as 50,000 hours, compared with less than 2000 hours for incandescent lamps, and have efficacy up to 50 lm/w compared with 15-29 lm/w for incandescent lamps. Thus, they are 300 percent more energy efficient.

Brightness

Physically, small light sources of high intensity such as incandescent lamp are excellent for light control but can be too bright for visual comfort

High-Intensity Discharge (HID) Lamp

Produces high intensity light within an arc tube contained in an outer bulb. The metallic gas within the arc tube may be mercury, sodium or a combination of other metallic vapors.

Supplementary Lighting

Provides a restricted area of high intensity, but supplements the general lighting

Direct-Indirect and General DIffuse Lighting

Provides approximately equal distribution of light upward and downward

SL Lamps

SL lamps are specially designed to fit directly in an incandescent lamp fixture. The lamp has a built-in ballast

Base

Several different types used to connect the lamp to the electric circuit and to support the lamp in the lamp holder

Short Arc Lamps or Compact Arc Lamps

Short arc lamps produce high intensity light from a small bulb, thus closely resembling a point source, which is important for critical light beam controls. These devices are HID lamps containing primarily xenon gas with mercury or argon as starter. These lamps are available from 100 watts to 30,000 watts. Xenon lamps are used primarily as spotlight, in projectors, and as searchlights.

Parts of a High Intensity Discharge (HID) Lamp

1. Base 2. Support and Lead-in wires 3. Heat Deflector 4. Arc Tube Support 5. Operating Electrodes 6. Inside Phosphor coating 7. Starting resistor 8. Starting electrode 9. Arc Tube 10. Outer bulb

Semi-direct Lighting

60% to 90% of the lamp output is directed downward and the remaining component serves to illuminate the ceiling

Semi-Indirect Lighting

60% to 90% of the light output is directed upward to the ceiling and upper walls

Indirect Lighting

90% to 100% of the light output of the luminaries is directed to the ceiling and upper walls of the room

Incandescent Light Sources

A lamp in which light is produced by the heating of a small filament inside of a glass. Incandescent glow increases relative to wattage of input. The filament produces a very small, luminous point source of radiation.

Luminaire Efficiency

A measure of the total light power output in lumens versus the total light power input of all lamps in the luminaire.

Mercury

A minute quantity of liquid mercury is placed in the tube to furnish mercury vapor

General Lighting

A system designed to give uniform and generally, though not necessarily, diffuse lighting throughout the area under consideration.

Rapid-Start Lamps

Ballasts for rapid-start lamps have separate windings to provide continous healing voltage for the lame electrodes. The lamp stats in less than once second, nearly instantaneously.

Phosphor

Coating inside the tube transforms ultraviolet radiation into visible light color of light produced depends on the composition of phosphor

Fluorescent Lamp (invented by Andre Claudo, also the inventor of neon lamp)

Contains mercury vapor, an electric arc is produced between the opposing electrodes generating some viisible light

Electrodeless Lamp

Electrodeless lamps include several new generation of lamps are promise to be the lamps of the future. They have good color - rendition property, high efficacy, an up to 50,000 or more operating hours. Their light output will not depreciate, because they have no electrodes. They are ideal for installation in difficult-to-reach areas. There are two types of electrodeless lamps: Electromagnetic / Microwave

Electroluminescent Lamps

Electroluminescent lamps emit light by direct excitation of phosphor from an alternating current. It can produce different colors by the mixing of phosphors. Although extremely efficient at out 200 lumens per watt, their use is limited to signs and decorative applications.

Electroluminescent Lamps

Emit light by direct excitation of phosphor from an alternating current. They can be made in any shape, size and form.

Incandescent Lamp (invented by Thomas Alva Edison)

Employs the principle of converting electrical energy into heat at a temperature that causes the filament to be incandescent (red or white hot).

Direct Lighting

Essentially all light output is directed downward, ceiling illumination is entirely due to light reflected from floor and room furnishings

Fluorescent Light Sources

Flourescent Lamp was developed in France in the early 1930's by Andre Claude, the inventor of the neon lamp. A fluorescent lamp contains electrodes at both ends of a tube that is filled with mercury vapor. When an electric current is impressed between the electrodes, ultraviolet energy is generated and converted to visible light by the phosphor coating on the inside of a fluorescent lamp is a mixture of many chemicals that emits visible light when excited by the ultraviolet energy generated by the mercury vapor. Different phosphors emits different colors. The commonly used is the white phosphor composed of calcium halophosphate

General Service Type

For general use in buildings. They are designed to have relatively good efficacy (15 - 25 lm/w), a moderate rated life (750 - 1000 hrs) and good color- rendering characteristics.

Electrodeless Lamps

Gaseous Lamps excited by means of electromagnetic or microwave energy without the use of electrodes

Button Rod

Glass rod support button

High Intensity Discharge (HID) Light Source

High Intensity Discharge (HID) lamps are a family of lamps that incorporate a high pressure arc tube within the lamp envelope. It is filled with metallic gases, such as mercury, argon, sodium, etc.

High Pressure Sodium (HPS) Lamps

High pressure sodium lamps contain xenon a starting gas and an amalgam of sodium and mercury that is partially vaporized when the lamp attains its operating temperature. HPS lamps are constructed with two envelopes: an inner envelope (arc tube) made with material that has electrical resistance to sodium and an outer envelope designed to protect the arc tube.

Cathode

Hot cathode at each end of the lamp

Hybrid Magnetic Type

It has a built-in electronic switching device to save energy by disengaging the cathode current after the lamp or lamps are started.

Intensity

Light intensity is expressed in candelas at various angles from the lamp or fixture

Local and Supplementary Lighting

Local Lightning-provides a small high level area of lighting without contributing to the general lighting

Bulb

Soft glass is generally used. Hard glass is used in some lamps to withstand higher bulb temperature and to protect against weather. Bulbs are made in various shapes and finishes.

Filament (Tungsten coil)

The filament used is tungsten, it may be straight coil or a coiled coil.

Lumen Depreciation

The loss of light, light output depreciates with time.

Rated lamp Life

The time elapsed when 50% of a group of lamps remain burning.

Miniature Reflector (MR) lamps

These lamps are a recent development. They are basically compact halogen lamps, such as the popular 50-100 watt MR-16 (2 inch-dia) lamp. Miniature reflector (MR) lamps are high in efficiency, easy to control and have high color quality. They are popular in interior and accent lighting application.

Extended Life Service

These lamps are designed with heavy filaments to operate at considerably lower than 3800 degrees F and a rated life ranging from 2,500 to 10,000 hours

Krypton Lamps

These lamps are filled with krypton gas and are designed for long life and good color rendition.

Rough and Vibration Services

These lamps are used in location subject such as on machinery or in mechanical equipment; used with heavy filaments and supports. They are designed with heavy tungsten filament and supports. Efficacy is between 10 and 19 lm/w.

Instant Start Lamps

These lamps operate without starters. The ballast provides a high enough voltage at about 680 volts to strike the arc instantly. Instant-start lamps are also called "Slimline Lamps". They are available in 211 to 75 watt rating.

Dichroic Reflector Lamps

These lamps transmit color selectively through a molecular layer of chemical coating, allowing only the desired wavelength of color to pass through. They are used to reduce the infrared wavelength, which causes heat. Typical application of these lamps is in retail merchandising display or on art paintings, where heat in the light beam is substantially reduced.

Hybrid Electronic Type

This is a combination of electronic and electromagnet type of ballast that consists of an input electromagnetic interference (emi) filter, a rectifier to convert standard frequency (50-60 hz) into DC, an inverter to convert DC to high frequency AC (20-30 khz)

Button Glass

This is heated during manufacturing and support wires stuck into it

Magnetic Type

This is the conventional electromagnetic core and coil type of ballast operating at 60 hz with secondary voltage between 200 and 700 volts.

Electronic Type

This is the newest type of ballast, with all-electronic components.

Electromagnetic

This type of electrodeless lamp uses the principle of electromagnetism to excite the gas fill in the lamp. It consists of a magnetic core-and-coil assembly at the lamp's center, but external to the lamp envelope.

Microwave

This type of electrodeless lamp utilizes a concentrated microwave generator to direct microwaves to a glass bulb filled with sulfur gas. Depending on the microwave power, the light generated can be of very high intensity. This lamp is ideal with a light tube- a tubular luminaire with light originating from one end. By controlling refraction and reflection in the tube, light can be uniformly emitted throughout the entire length of the tube, which may stretch up to several hundred feet.

Tungsten - Halogen Lamps

This type of lamp makes use of the halogen regenerative cycle to reduce blackening by depositing the evaporated tungsten atoms on the filament. The bulb of a halogen lamp must be compact in size and thus is normally made wit quartz to withstand extremely high temperatures.

Combined General and Local Lighting

Used in spaces where the general visual task is low but supplementary lighting is required in a limited area for a particular task

Gas

Usually a mixture of nitrogen and argon is used in most lamps of 40 or higher to retard evaporate of filament.

Gas

Usually argon gas or a mixture of inert gases at low pressure. Krypton is sometimes used

Plant Growth Lamps

are designed to stimulate photosynthesis

Neon lamps

are non-coated cold-cathode lamps operating at extremely high voltages (exceeding 500 volts). The lamp tube is small in diameter and can easily be bent into any shape. Different gas fills, generate different colors, e.g. neon emits red, and argon and mercury together emit blue and, combined with a blue-absorbing glass tube will emits green. Neon lights are used primarily for signs and decorative applications.

Cold Cathode Lamps

are phosphor-coated lamps filled with mercury vapor and argon gas that operate at a voltage of 700 to 1000 volts. lth different as fills, they can also produce different colors. Cold cathode lamps are used for decorative lighting, such as for curved coves and in locations where replacing a lamp is difficult. Cold cathode lamps are often used in lieu of neon lights in the interiors of buildings.

Subminiature Lamps

constitute a family of tiny fluorescent lamps with a 7mm dia. (T 2 1/2 in.), 1-3 watts. They are used principally for backlight of LCD or for lightning instruments.

Reflector Lamps

have an internal reflector to cover up a portion of the bulb; thus they reflect the light to the open aperture of the lamp at a higher intensity than the general-service type lamps. They are useful for display or cove lighting applications.

Black lamps

produce energy in the near ultra violet range

UV Lamp

produces ultraviolet energy for germicidal use

Average Lumen

the average of the initial lumens output at the end of the rated life of the lamp.

Beam Lumens

the initial lumens output within the central beam.

Initial Lumens

the initial rated light power output.

Mean Lumens

the lumens output at 40% of the rated life of the lamp.

Tube

usually straight glass tube, may also be circular or U-shape


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