misspelledsearch.com:lighting fixture repairinformation page
If you cannot find the information you are searching for on this page, we suggest searching Google with the correct spelling "lighting fixture repair":
Lighting refers to either artificial light sources such as lamps or to natural illumination of interiors from sunlight. Lighting represents a major component of energy consumption, accounting for about 25 percent of all energy consumed worldwide. In major cities, light pollution is of growing concern. Artificial lighting is provided today by electric lights, but previously by gas, candles or oil lamps. Proper lighting can enhance task performance or aesthetics, while there can be energy wastage and adverse health effects of lighting which is too intense. Indoor lighting is a form of fixture or furnishing, and a key part of interior design. Lighting can also be an intrinsic component of landscaping. Dark lighting in a concert hall allow laser effects to be visible
Energy consumptionArtificial lighting consumes approximately one quarter of all energy consumed worldwide. In homes and offices from 20 to 50 percent of total energy consumed is due to lighting. Most importantly, for some buildings over 90 percent of lighting energy consumed can be an unnecessary expense (Hawken, 2000). Thus lighting represents a critical component of energy use today, especially in large office buildings where there are many alternatives for energy utilization in lighting. There are several strategies available to minimize energy requirements in any building:
Health effects of lightingIt is valuable to provide the correct light intensity and color spectrum for each task or environment. Otherwise energy not only could be wasted, but over-illumination can lead to a gamut of adverse health and psychological impacts. Specification of illumination requirements is the basic concept of deciding how much illumination is required for a given task. Clearly much less light is required to illuminate a hallway or bathroom compared to that needed for a word processing work station. Prior to 1970 {and too often even today} a lighting engineer would simply apply the same level of illumination design to all parts of the building without considering usage. Generally speaking the energy expended is proportional to the design illumination level. For example a lighting level of 80 footcandles might be chosen for a work environment involving meeting rooms and conferences, whereas a level of 40 footcandles could be selected for building hallways. If the hallway standard simply emulates the conference room needs, then twice the amount of energy will be consumed as is needed for hallways. Unfortunately, most of the lighting standards even today have been speciifed by industrial groups who manufacture and sell lighting, so that a historical commercial bias exists in designing most building lighting, especially for office and industrial settings. Beyond the energy factors being considered, it is important not to overdesign illumination, lest adverse health effects such as headache frequency, stress and increased blood pressure be induced by the higher lighting levels. In addition glare or excess light can decrease worker efficiency (DiLouie, 2006). Analysis of lighting quality paricularly emphasizes use of natural lighting, but also considers spectral content if artificial light is to be used. Not only will greater reliance on natural light reduce energy consumption, but will favorably impact human health and performance. For example, it is clear that student test scores are improved for children who learn in the presence of greater natural light (Bain, 1997). Lighting designArchitect lampsLighting design as it applies to the built environment, also known as 'architectural lighting design', is both a science and an art. Comprehensive lighting design requires consideration of the amount of functional light provided, the energy consumed, as well as the aesthetic impact supplied by the lighting system. Some buildings, like surgical centers and sports facilities, are primarily concerned with providing the appropriate amount of light for the associated task. Some buildings, like warehouses and office buildings, are primarily concerned with saving money through the energy efficiency of the lighting system. Other buildings, like casinos and theatres, are primarily concerned with enhancing the appearance and emotional impact of architecture through lighting systems. Therefore, it is important that the sciences of light production and luminaire photometrics are balanced with the artistic application of light as a medium in our built environment. These electrical lighting systems should also consider the impacts of, and ideally be integrated with, daylighting systems. Factors involved in lighting design are essentially the same as those discussed above in energy conservation analysis. The Illuminating Engineering Society of North America (IESNA), in conjunction with organizations like ANSI and ASHRAE, publishes guidelines, standards, and handbooks that allow categorization of the illumination needs of different built environments. Manufacturers of lighting equipment publish photometric data for their products, which defines the distribution of light released by a specific luminaire. This data is typically expressed in standardized form defined by the IESNA. The International Association of Lighting Designers (IALD) is an organization which focuses on the advancement of lighting design education and the recognition of independent professional lighting designers. Those fully independent designers who meet the requirements for professional membership in the association typically append the abbreviation IALD to their name. The National Council on Qualifications for the Lighting Professions (NCQLP) offers the Lighting Certification Examination which tests rudimentary lighting design principles. Individuals who pass this exam become ‘Lighting Certified’ and may append the abbreviation LC to their name. This certification process is the only national examination in the lighting industry and is open not only to designers, but to lighting equipment manufacturers, electric utility employees, etc. Generally speaking there is no legal or practical requirement for the lighting design team to possess the certifications discussed; in fact, some of the best lighting designs have been produced by architects or physicists who are unfettered by historical conventions rooted in the 1950s as are many ways of thinking of IESNA and IALD. Mathematical Modeling is normally used for complex lighting design, whereas, for simple configurations, tables and simple hand calculations can be used. Based on the positions and mounting heights of the fixtures, and their photometric characteristics, the proposed lighting layout can be checked for uniformity and quantity of illumination. For larger projects or those with irregular floor plans, lighting design software can be used. Each fixture has its location entered, and the reflectance of walls, ceiling, and floors can be entered. The computer program will then produce a set of contour charts overlaid on the project floor plan, showing the light level to be expected at the working height. More advanced programs can include the effect of light from windows or skylights, allowing further optimization of the operating cost of the lighting installation. The Zonal Cavity Method is used as a basis for both hand, tabulated, and computer calculations. This method uses the reflectance coefficients of room surfaces to model the contribution to useful illumination at the working level of the room due to light reflected from the walls and the ceiling. Simplified photometric values are usually given by fixture manufacturers for use in this method. Computer modelling of outdoor flood lighting usually proceeds directly from photometric data. The total lighting power of a lamp is divided into small solid angular regions. Each region is extended to the surface which is to be lit and the area calculated, giving the light power per unit of area. Where multiple lamps are used to illuminate the same area, each one's contribution is summed. Again the tabulated light levels (in lux or foot-candles) can be presented as contour lines of constant lighting value, overlaid on the project plan drawing. Hand calculations might only be required at a few points, but computer calculations allow a better estimate of the uniformity and lighting level. Practical lighting design must take into account the gradual decrease in light levels from each lamp owing to lamp aging, lamp burnout, and dirt accumulation on fixture and lamp surfaces. Empirically-established depreciation factors are listed in lighting design handbooks. Proper selection of fixtures is complicated by the requirement to minimize the veiling reflections off of printed material. Since the exact orientation of printed material may not be closed controlled, a visual comfort probability can be calculated for a given set of lighting fixtures. Lighting Types are classified by intended use as general, localized, or task lighting, depending largely on the distribution of the light produced by the fixture.
Methods of lighting are:
Forms of Lighting include alcove lighting, which like most other uplighting is indirect. This is often done with fluorescent lighting or rope light, or occasionally with neon lighting. It is a form of backlighting. Soffit lighting can be general or a decorative wall-wash, sometimes used to bring out texture (like stucco or plaster) on a wall, though this may also show its defects as well. The effect depends heavily on the exact type of lighting used. Recessed lighting (often called "pot lights" in Canada and "can lights" in the U.S.) is popular, with fixtures mounted above the ceiling so as to appear flush with it. These downlights use narrow spotlights, or wider-angle floodlights, both of which are bulbs having their own reflectors. They may also have their own reflector built-in to the fixture, so that they can use common, less costly bulbs. Either type can be incandescent, fluorescent, HID or LED, though only incandescents or LEDs make narrow enough spots. True can lights are uplights, resting on the floor in a can-like fixture, or mounted on a spike or even in the ground for plants or outdoors. Track lighting, invented by Lightolier, was popular at one point because it was much easier to install then recessed lighting, and individual fixtures are decorative and can be easily aimed at a wall. It has regained some popularity recently in low-voltage tracks, which often look nothing like their predecessors because they do not have the safety issues that line-voltage systems have, and are therefore less bulky and more ornamental in themselves. A master transformer feeds all of the fixtures on the track or rod with 12 or 24 volts, instead of each having its own. There are traditional spots and floods, as well as other small hanging fixtures. A modified version of this is cable lighting, where lights are hung from or clipped to bare metal cables under tension. The lamp is probably the most common fixture, found in every home and many offices. The standard lamp and shade that sits on a table is general lighting, while the desk lamp is considered task lighting. Magnifier lamps are also task lighting. The illuminated ceiling was once popular in the 1960s and 1970s but fell out of favor after the 1980s. This uses diffuser panels hung like a suspended ceiling below fluorescent lights, and is considered general lighting. Other forms include neon, which is not usually intended to illuminate anything else, but to actually be an artwork in itself. This would probably fall under accent lighting, though in a dark nightclub it could be considered general lighting. Underwater accent lighting is also used for koi ponds and the like. FixturesWall-mounted light with shadows.Lighting fixtures come in a wide variety of styles for various functions. Some are very plain and functional, while some are pieces of art in themselves. Nearly any material can be used, so long as it can tolerate the heat and is in keeping with safety codes. A sconce is a wall-mounted fixture, particularly one that shines up and sometimes down as well. A torchiere (tour-she-AIR or tour-SHARE) is an uplight intended for ambient lighting. It is typcially a floor lamp but may be wall-mounted like a sconce. Concert and theatre lighting use special types of fixtures. Conventional lighting consists of stationary lights that can only be moved manually, by means of adjusting, or focusing the fixture with a yoke. Automated lighting fixtures use digital electronics to adjust the color, position, beam angle, brightness, and other special effects. In the United States, automated lighting fixtures are normally controlled by the United States Institute of Theatre Technology Digital Multiplex - 512 Channel Standard Protocol, or simply DMX-512. The protocol runs on standard three pin XLR cable, although, some older theatres still use five pin DMX cabling. Generally, standard sound XLR cabling is not suitable for lighting, because the gauge of the wire is too small. Conventional Fixtures are stationary or 'fixed' and normally controlled by a power cable, allowing the fixture to output a beam of light with a brightness of 0 to 100 percent. Power for the fixtures is provided by dimmers which receive control signal, either digitally multiplexed (DMX) or analog + / − 12v from the main lighting desk or console, where all of the lights used in a production are controlled. A short cable is normally hardwired or connected to the body of the light and has an electrical connector on the end. Connectors are fuseless, as the fuse for the fixture is provided at the dimmer end of the circuit. Types of fixtures include:
Although these fixtures are of the 'fixed' variety, they are adjustable to a huge degree. All Theatrical Lighting Fixtures should have a steel or metal color or 'gel' frame, which slots into a receiver at the front of the fixture. These are used for holding acrylic color 'gel', which is available in many hundreds of shades and hues. Profiles are Used for front (face) lighting and, with the insertion of a 'gobo' (stainless steel pattern) are used for break-up effects or projecting simple images onto the stage floor or set/backdrop. Profiles have one or two convex or plano-convex lenses, which can be adjusted to create a larger or smaller beam, with a hard or soft edge, and have steel shutters placed at the focal point of these lenses, to cut away unwanted portions of the beam. Fresnel fixtures are used for color washes, side, front and back-lighting. These have a pebbled lens with concentric rings, which results in a large hazy circle around the focal point of the lantern. The beam size is adjusted by a screw, which actually moves the bulb of the fixture forwards and backwards within the body of the lamp. Large metal 'barndoors' (four in total) are affixed to the front of the lamp on a rotating ring, to cut away unwanted parts of the beam. Prism Convex' fixtures or 'PCs', are much the same as fresnels, but with a prism convex lens instead of fresnel lens. The body of PCs is longer than fresnels. PCs produce a more focused beam than fresnels, and are suitable for many of the same applications as fresnels and profiles. PARs or PAR cans are among the most simple and widely-used theatrical lighting fixtures. They basically consist of a tube of steel or aluminum with a rounded removable end, for changing lamps (bulbs). PAR lamps contain a reflector (Parabolic Aluminumized Reflector), filament and lens in an enclosed glass envelope, and have various beam types:
Flood fixtures usually have a halogen tube bulb, backed by a curved symmetric or asymmetric reflector, to give a flat beam to be used for lighting sets or backdrops from above or below. LampsCommonly referred to as 'light bulbs', lamps are the removable/replaceable portion of a luminaire which convert electrical energy to both visible and non-visible electromagnetic energy. Common characteristics used to evaluate lamp quality include efficiency measured in lumens per watt, typical lamp life measured in hours, and Color Rendering Index on a scale of 0 to 100. Cost of replacement lamps is also an important factor in any design. Incandescent lampsThe incandescent light bulb was the first type of bulb, and is inefficient at converting electricity to light. About 90% of the energy input is wasted as heat. This excess heat is then dumped into the air which, in warm climates, must then be cooled by ventilation or air conditioning, resulting in more energy wastage. Due to their heat output, incandescent bulbs can cause burns or start fires if used improperly. Halogen bulbs are an improved incandescent. Light energy output is about 15% of energy input, instead of 10%, allowing them to produce about 50% more light from the same amount of electrical power. The bulb capsule is under high pressure instead of a vacuum or low-pressure noble gas. As well as being much smaller and having a hotter filament temperature, this causes halogen bulbs to have a very hot surface. This means that glass bulbs can explode if broken or brought into contact with cool materials such as water, or if operated with residue such as fingerprints on them. The risk of burns or fire is also greater than other bulbs, leading to their prohibition in some places. Halogen capsules can be put inside regular bulbs or dichroic reflectors, either for looks or for safety. Good halogen bulbs produce a sunshine-like white light, while regular incandescents produce a light between sunlight and candlelight. People sometimes find them psychologically pleasing over other types of bulbs due to the more natural colour, which lights some skin tones and other artifacts more accurately. Fluorescent lampsFluorescent bulbs are about 40% efficient, meaning that for the same amount of light they use 1/4 the power and produce 1/6 the heat of a regular incandescent. Fluorescents were limited to linear and a few circular ones until the 1980s, when the compact fluorescent was invented. The compacts can plug into their own fixture, or fit in to a standard screw base for self-ballasted ones. All last far longer than incandescents, but do have some starting trouble in very cold weather when installed outside. Fluorescents most often come in cool white (CW), with some home bulbs being a warm white (WW), which has a pinkish tint. In between there is an "enhanced white" (EW), which is more neutral. There is also a very cold daylight white (DW) which is rather unpleasant to most people and therefore rarely used. Compact ones are usually considered warm white, though many have a yellowish cast like an incandescent. Because the above terms are entirely relative and almost arbitrary, color temperature and/or the color rendering index (CRI) are used as absolute scales of color for fluorescents, and sometimes for other types of lighting. HID lampsHigh-intensity discharge lighting first came about with the mercury-vapor streetlights, and later the high-pressure sodium ones with their characteristic orange color. Modern ones are metal halide, used in everything from headlights to floodlights, and with a more pleasant color balance. Like fluorescents, all HID bulbs require a ballast, but they also require a few minutes (or seconds for headlights) to warm up after "igniting". HID bulbs are over 60% and up to 80% efficient. LED lampsLEDs are a very recent introduction to the market, and they are still extremely expensive for any decent-sized bulb. They do however last an extremely long time, up to 100,000 hours (compared to around 10,000 for fluorescent and 1,000 for incandescent). These have come about only since the white LEDs they use, and in turn the blue LEDs which they were based on. It appears that for now these will be most useful and cost-effective in smaller applications, starting with nightlights. Colored LEDs can also be used for accent lighting, even in fake ice cubes for drinks at parties. They are also being increasingly used as Christmas lights. White LEDs are about the same efficiency as other fluorescents, while red ones can be up to 90% efficient. LED Technology for theatrical and concert applcations is still in its infancy, but is advancing at an incredible rate. Patent disputes of RGB colour mixing ideas are currently slowing development, despite the fact many products are being released that take advantage of red, green, blue, and sometimes white, LEDs to mix colours. LED technology is useful for lighting designers because of its low power consumption, low heat generation, instantaneous on/off control, continuity of colour throughout the life of the diode and relatively low cost of manufacture. In the last few years, software has been developed to merge lighting and video by enabling lighting designers to stream video content to their LED fixtures, creating low resolution video walls. Vehicle lightingVehicles typically include headlights and tail lights. Headlights are white or yellow lights placed in the front of the vehicle, designed to illuminate the upcoming road and to make the vehicle more visible. Tail lights are always red and are placed in the rear to quickly alert other drivers about the vehicle's direction of travel. In the image to the right, the top (white portion) of the tail light is the back-up lamp, which when lit, is used to indicate that the vehicle's transmission has been placed in the reverse gear, warning anyone behind the vehicle that it is moving backwards, or about to do so. In addition to lighting for useful purposes, automobiles increasingly feature ornamental lighting. In the late 1960s and early 1970s, manufacturers would sometimes backlight their logos and or other translucent panelling. In the 1990s, a popular trend was to customize vehicles with neon lighting, especially underneath the body of a car. In the 2000s, neon lighting is increasingly yielding to digital vehicle lighting, in which bright LEDs are placed on the car and operated by a computer which can be customized and programmed to display a range of changing patterns and colors, a technology borrowed from Christmas lights. See other topics and inventor articlesOther articles
Inventors
Bibliography
External links
This lighting fixture repair index site has been developed to help wayward users find the information they are looking for, no matter how they are mistakenly spelled or mistyped. This site is designed to help users find lighting fixture repair information for the following query variants:
If you would like to add or correct the content of this site, or if you are interested in supporting the efforts of misspelledsearch.com by placing your product information on these lighting fixture repair pages, please contact mistype@gmail.com for details. This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "lighting". | |||||||||||||||||||