Mercuryvapor lamp techsciencenews online reference. Philips mercury vapor lamps last at least 24,000 hours. This is different from fluorescents which use the mercury vapor arc to create a weaker light that mainly creates uv light to excite the phosphors. A mercury vapor lamp is a type of high intensity discharge hid lamp that is typically used for commercial and outdoor lighting. During the last 15 years the luminous efficacy and the colour appearance of these mercury vapour lamps have been much improved by the application of europiumactivated. Phosphor coated bulbs offer a better color rendering index than either high or low pressure sodium lamps. Mercury vapor lamps and their relatives are often used because they are relatively efficient. From street lighting to parking lots, major portions of our infrastructure depend on this century old lighting technology. The mechanism in mercury vapour lamp is more involved and sequential. Highpressure mercuryvapor lamps are those lamp commonly used for general lighting purposes. The modern highpressure mercury vapor lamp is developed in the year 1936 by philips nederland no individual names are available. Uv medium pressure mercury vapour lamps these uv lamps, emit across the entire spectrum of ultraviolet light uva, uvb and uvc with peak emission in the uva range at 366 nm. Phosphor coated bulbs offer better color rendition than either high or low pressure sodium vapor lamps. This results in a warmer color appearance and higher color rendering than standard mercury lamps.
During the last 15 years the luminous efficacy and the colour appearance of these mercury vapour lamps have been much improved by the application of europiumactivated phosphors. Philips mercury vapor 250watt high pressure hid light bulb is ideal for use in landscape lighting, dusk to dawn, roadway, parking lots, floodlights and security fixtures. Mercury vapor lamps also offer a very long lifetime, as well as intense lighting for several applications. High intensity discharge hid4 is the term commonly used for several types of lamps, including metal halide, high pressure sodium, and mercury vapor lamps. There are two types of mercury vapor light bulbs sold in the. The xenon gas which is easily ionized, facilitates striking the arc when voltage is applied across the electrodes. This blog showcases in detail the working of high pressure sodium vapour lamp.
High output germicidal lamp types highoutput quartz germicidal lamps operate between 600 ma and 800 ma t5 or t6 configuration 15mm or 19mm od approximately 2 times the uv output of standard germicidal lamps same lengths as standard germicidal lamps available same relationship and limitations in regard to. The fact that the high pressure mercury vapour lamp could be introduced successfully as a practical light source, is due to the favourable spectral light distribution, the high luminous efficiency, the relatively small lamp dimensions and the possibility of an extensive range. High pressure mercury vapour lamps for general lighting. Ballast circuit with power factor correction capacitor. Ep0215524a1 highpressure mercury vapour discharge lamp. High pressure mercury lamps kolorlux standard 50w, 80w, 125w, 250w and 400w kolorlux deluxe 50w, 80w, 125w, 250w and 400w data sheet product information kolorlux mercury vapor lamps are often used due to their relative efficiency. When a mercury vapor lamp is to be disposed, it is subject to the current epa toxicity characteristic leaching procedure tclp disposal criteria. A mercury vapour lamp is a highpressure, electric arc discharge lamp that provides intense illumination over a selected range of wavelengths. In a high pressure sodium lamp, a compact arc tube contains a mixture of xenon, sodium and mercury.
Liquid mercury droplets collect at the lamps cold spot. A sodiumvapor lamp is a gasdischarge lamp that uses sodium in an excited state to produce light at a characteristic wavelength near 589 nm two varieties of such lamps exist. A high pressure sodiumvapor lamp a sodiumvapor lamp is a gasdischarge lamp that uses sodium in an excited state to produce light at a characteristic wavelength near 589 nm. A fluorescent lamp tube is filled with a gas containing low pressure mercury vapor and argon, xenon, neon, or krypton. Mediumpressure lamps draw a much greater current than lowpressure lamps, leading to a rapid rise in the mercury vapor pressure. Even though more cleaning may be required for medium and amalgam lampbased systems, because they have a smaller number of lamps in the uv unit, these systems can. Us4199708a lowpressure mercury vapor discharge lamp. High pressure mercury vapor lamps are those lamp commonly used for general lighting purposes. Dec 21, 2015 the modern high pressure mercury vapor lamp is developed in the year 1936 by philips nederland no individual names are available. The inner surface of the lamp is coated with a fluorescent and often slightly phosphorescent coating made of varying blends of metallic and rareearth. Butyl methoxy dibenzoylmethane was irradiated for 100 h in a quartz immersion well photoreactor, equipped with a medium pressure mercury vapor lamp. During the last 15 years the luminous efficacy and the colour appearance of these mercury vapour lamps have been much improved by the application of europium. The heat generated by the arc then vaporizes the mercury and sodium.
An arc is established between two electrodes in a gasfilled tube, causing a metallic vapor to produce radiant energy. Here also, the excited electrons of mercury atoms relax by emitting characteristic but ultraviolet 254nm, invisible light. Low pressure mercury lamps have been manufactured in jelight company inc. The wall load power consumption divided by the surface area of the outer wall of the discharge vessel has a value of at least 25 wcm 2. It has a bluish green appearance and features a low initial cost. Mercury vapour lamps dealing with breakages some items of laboratory equipment contain mercury vapour lamps to generate uv light. High and low pressure uv mercury vapour lamps heraeus manufactures low and high pressure mercury vapour lamps used for applications such as photochemical processing, fluorimetry, mercury analysers, medical and environmental equipment, and fixed wavelength detectors. The outer bulb may be clear or coated with a phosphor. In mediumpressure mercuryvapor lamps, the lines from 200600 nm are present. These lamps are mostly used for street lighting as well as industrial uses. Leakage reactance high loss control gear is used for 5w and 180watt lamps.
The luminous efficacy of any discharge lamp falls as wattage is. Highpressure mercury vapour lamps performance specifications. The clear mercury bulb has a bluish green appearance and the deluxe white has a higher color rendering. Among the light sources in use for general lighting, high pressure mercury vapour h.
Sodium lamps were first produced commercially by philips in holland in 1932. The photodegradation of butyl methoxy dibenzoylmethane was investigated in cyclohexane by roscher et al. The aperture phosphorcoated lamps that jelight company produces employ the same basic design as the doublebore, low pressure mercury vapor lamps with the exception of a special phosphor coating. Because they have a large installed base, there continues to be applications for replacement and retrofit lamps. Mar 23, 2015 just a bit of a ramble about two mercury vapour lamps with some illumination of said lamps.
Both types of high pressure mercury lamp have a lifesurvival characteristic similar to son lamps but mbf lumen maintenance reduces more throughout its life. The sodium is mixed with other impurities to create a more white light. Best applications for mercury vapor lamps eye lighting. In medium pressure mercury vapor lamps, the lines from 200600 nm are present. Hach replacement uv for toc analyzers, arc imaging, chromatography, photochemistry, calibration of uv detectors, calibrations of spectrophotometer, and more. The mercury vapor lamp is a high intensity discharge hid. Mercury vapor lighting is the oldest hid technology. Ballasts of the correct size and type are required to operate mercury lamps on any standard electrical. As pressure increases the chance of multiple collisions gets increased. The reason for the creation of this second category of mercury lamp was to allow the efficacy to be maintained as high as possible for low wattage sources. The sputtered electrons from the filaments, after having been accelerated by high voltage, hit the mercury atoms.
Dec 31, 2018 in case of fluorescent lamp the mercury vapour pressure is maintained at lower level such that 60% of the total input energy gets converted into 253. All mercury vapor lamps contain some amount of mercury. Mar 10, 2020 high pressure sodium lamps or hps lamps march 10, 2020 february 24, 2012 by electrical4u high pressure sodium lamps also known as hps lamps or hps lights are a type of sodium lamp that is widely used in industrial lighting and many public outdoor areas. Engineering high intensity discharge bulletin mercury lamps. Mercury vapor is the original and now the oldest hid technology and has been supplanted by other hid types that offer higher efficiencies and better color properties.
Such lamps generate an atmosphere of mercury vapour at high pressure. The tube contains a few milligrams of mercury and around 2550 torr of pure argon as a buffer gas to carry the discharge while the lamp warms up, producing. Hps lamp is the better version of its counterpart lps lamp. In case of fluorescent lamp the mercury vapour pressure is maintained at lower level such that 60% of the total input energy gets converted into 253. The first highpressure mercury lamp, similar to the ones used today, was introduced in 1934 in the 400watt size.
Mercury vapor standard hpl high pressure mercury philips. This standard specifies the performance requirements for high pressure mercury vapour lamps for general lighting purposes, with or without a red correcting fluorescent coating. A mercuryvapor lamp is a gas discharge lamp which uses mercury in an excited state to produce light. What are the advantages and disadvantages of the mercury lamp. Medium pressure lamps produce the greatest uv output per unit length of lamp of the 3 lamp types. Low pressure and high pressure sodium vapour lamp gktoday. Lamps now available range in size from 40 watts to watts.
Further improvement is achieved in many of the lamp types by the addition of a phosphor coating to the inside surface of the outer bulb. It was the original metal vapor style of light fixture to be mass produced for general purpose lighting. The mercury vapor raises the gas pressure and operating. For some of the requirements given in this standard, reference is made to the relevant lamp data sheet. The mercury vapor lamp is a high intensity discharge lamp. Per unit area, the effective germicidal output of a mediumpressure lamp is much greater up to 30 times than a lowpressure lamp, allowing high flow rates to be treated using. What are the advantages and disadvantages of the mercury lamp, sodium vapour lamp and xenon lamp used in photocatalysis. After that the arc then heats up the mercury and the mercury vapor then lights, giving the lamp a bluish color. They are commonly used in public parking lots, roadways, and other security areas. This coating covers more than 70% of the diameter of the lighted length of the lamp. Ignitors are only required up to 90 watt lamp rating. Both philips lamps, one brand new 50w and a very badly tortured 80w that still somehow runs. Better efficiency, life and size are few of the advantages of hps lamp over lps lamp. High pressure sodium lamps or hps lamps electrical4u.
Mercury vapor lamps feature low initial cost, but have higher operating costs than hps or metal halide due to its lower efficiency. What are the advantages and disadvantages of the mercury. It uses an arc through vaporized mercury in a high pressure tube to create very bright light directly from its own arc. Lowpressure sodium lamps are highly efficient electrical light sources, but their yellow light restricts applications to outdoor lighting, such as street lamps, where they are.
Even though more cleaning may be required for medium and amalgam lamp based systems, because they have a smaller number of lamps in the uv unit, these systems can. For special applications, in addition to the usual mercury lamps, helios has developed a series of uv lamps metal halide adding doping elements metal. The mercury vapor lamp works by creating an electric current to mercury vapor within a sealed glass jacket. Introduction the mercury vapor lamp is a high intensity discharge lamp. They have an efficiency of up to 190 lumens per watt compared to an incandescent street lamp which has between 15 and 19. The construction and applications of sodium vapour lamps. Mercuryvapor lamp an overview sciencedirect topics. Sodium vapor lamps are some of the most efficient lamps in the world. High output another low pressure mercury lamp option is our standard and highoutput ho uvc lamps that use mercury vapor to emit uvc light. Mercury lamps are used primarily for general street, parking and hibay industrial lighting applications where good efficiency and long life is desired and. The first high pressure mercury lamp, similar to the ones used today, was introduced in 1934 in the 400watt size. Just a bit of a ramble about two mercury vapour lamps with some illumination of said lamps. Mercury vapour pressure is typically around ten atmospheres. Again transition of the electrons requires least amount of input energy from a colliding electron.
The luminous efficacy of any discharge lamp falls as wattage is reduced. The lamps can be constructed to emit primarily in the uva around 400 nm or uvc around 250 nm. The arc discharge is generally confined to a small fused quartz arc tube mounted within a larger borosilicate glass bulb. The lamp works by creating an electric arc through vaporized sodium metal. New high power amalgam lamps are significantly more powerful than low pressure lamps. At the heart of the lamp is an arc tube which is fabricated from quartz, with a tungsten electrode disposed at either end.
Lowpressure mercury vapor discharge lamp having a closed elongated lamp envelope and comprising at least two electrodes disposed near a first end of the lamp envelope, at least one electrode is situated at the end of at least one inner tube situated within and sealed in a gastight manner to the lamp envelope, this inner tube having at least one opening to the inside of the. Aug 20, 2016 a fluorescent lamp tube is filled with a gas containing low pressure mercury vapor and argon, xenon, neon, or krypton. The light output of a selfballasted lamp is a blend of incandescent and mercury vapor light. Nov 14, 20 mercury vapor lighting is the oldest hid technology. Once the mercury droplets reach their peak temperature. Sodium is the last material to vaporize as sodium vapor strikes an arc over 240 c. This gives a typical diffuse mediumpressure uv spectrum see figure 3. May 22, 20 the mechanism in mercury vapour lamp is more involved and sequential. Highpressure mercury vapour discharge lamp having a discharge vessel of gastight radiation transmitting ceramic material, provided with a filling comprising a rare gas, mercury, sodium halide and thallium halide. A mercury vapour lamp is a high pressure, electric arc discharge lamp that provides intense illumination over a selected range of wavelengths. Highpressure mercury lamps are available in versions where the discharge takes place in vaporized mercury only and in versions in which metal halides are added so that the discharge takes place in mercury vapor and in vaporized metals from the metalhalide components 2, 3. Mercury lamps get dimmer over time and rarely burn out, so it is wise to replace them and restore light level. This standard specifies the performance requirements for highpressure mercury vapour lamps for general lighting purposes, with or without a red correcting fluorescent coating.
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