Works through the combined effect of electric discharge through mercury vapours and fluorescence from phosphors (luminescent materials). Full-size fluorescent lamps are available in several shapes, including straight, U-shaped, and circular configurations. Metal halide lamps are a form of the light source that creates light via passing an electric arc through a gaseous mixture of mercury vapor and vapor of some metal halides. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Difference between a Private Limited Company and Public Limited Company in India, Sub-schools of Vedanta and their Propounders, Current Affairs Articles Compilation [PDF] - March, 2023, Current Affairs [PDF] - March 16-31, 2023, Works by electric discharge (passage of electricity through sodium vapours at high/low pressure). All Rights Reserved. Thus, they run cooler for the same effective light output. But, overall, that's about it! The arc tube is designed with aluminum oxide ceramic because it opposes the acidic effects of alkalis like Na (sodium). This signal will activate an arc with the xenon gas. When the lamp is switched on, the sodium vaporises and an arc is established. 1. Ballasts with a high ballast factor can help in this goal by driving more light from fewer fixtures. HPS light costs differ based on the particular fixtures, but are cheap compared to LEDs. The higher the lamp power, the higher will be the amalgam temperature. In applications where constant illumination is important for safety and security, a backup system is often required. Can replace incandescent bulbs that are roughly 3 to 4 times their wattage, but can cost up to 10 times more than comparable incandescent bulbs. Hence, the light from the mercury vapour lamp is white. Why capacitor is used in sodium Vapour lamps? In addition, HID lamps require a warm-up period to achieve full light output. 2022 Superior Lighting All Rights Reserved. The low pressure sodium lamp needs a high voltage, so it uses a special transformer ballast circuit. Because of their numerous advantages, metal halide lamps are used extensively in outdoor applications and in commercial interiors. This lamp is the most efficiently used lamp in different applications in the world. A typical high pressure sodium lamp can put out between 50 and 140 lumens per watt. This construction led the General Electric Company to use the tradename "Lucalox" for its line of high-pressure sodium lamps. [23], High-pressure sodium (HPS) lamps have been widely used in industrial lighting, especially in large manufacturing facilities, and are commonly used as plant grow lights. The high pressure sodium vapor lamp gives a wide spread of illumination with a golden white light. The big bulbs are just blinding. The HPSV lamp is the most frequently used in street lighting. Compare the Difference Between Similar Terms. Other HID types that offer higher LPW and better color properties have largely superceded the use of this lamp. Mercury vapour lamp is quite suitable for lighting applications. These types of lamps have up to 190 lumens of efficiency for each watt as compared to an incandescent lamp. The advantages of sodium vapor lamps include the following. Low-pressure sodium (LPS) lamps have a borosilicate glass gas discharge tube (arc tube) containing solid sodium and a small amount of neon and argon gas in a Penning mixture to start the gas discharge. Two varieties of such lamps exist: low pressure and high pressure. It will not immediately restrike when rapidly switched off then back on because the vapor pressure prevents this happening. For indoor lighting, the yellow color is not suitable. The energy savings for existing fluorescent lighting can be increased by: Figure 6.3.5. Moreover, the most common compound is sodium iodide. Make sure you are giving the ambiance you intend with the right lights from Superior Lighting. Sodium vapor lamps are similar to the mercury vapor lamps, as they come in both low pressure and high pressure versions. Most of the times, the metal halides are compounds containing bromine and iodine as the halide component. Advantages The advantages of sodium vapor lamps include the following. Metal Halide Lighting. Alabama Power. Sodium, the major element used, produces the "golden" color that is characteristic of HPS lamps. There is a brief warm-up period for the lamp to reach full brightness. This regenerative process continues repeatedly, creating a self-cleaning action on the inner surface of the glass tube or bulb. Come in a variety of sizes and shapes and are being used as energy saving alternatives to incandescent lamps. Lets now look at several different types of incandescent bulbs. LPS lamps have an outer glass vacuum envelope around the inner discharge tube for thermal insulation, which improves their efficiency. In addition, the electrodes are only a few inches apart (at opposite ends of a sealed arc tube) and the gases in the tube are highly pressurized. This page titled 6.3: Types of Lighting is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Sarma V. Pisupati (John A. Dutton: e-Education Institute) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request. The lamp starting is achieved by a high voltage pulse from an electronic igniter circuit which ceases to function once the main arc has been struck. Figure 6.3.3 shows a picture taken with an Infrared camera comparing the heat produced by a halogen and a compact fluorescent light bulb. @media (max-width: 1171px) { .sidead300 { margin-left: -20px; } }
The higher the temperature of the amalgam, the higher will be the mercury and sodium vapor pressures in the lamp and the higher will be the terminal voltage. The lamp takes several minutes to reach full brightness. The glass bulb is filled with an inert gas such as nitrogen or argon which helps to reduce filament evaporation, allowing an operating life expectancy of about 1,000 hours. It is used in street lighting & other illumination. The high-pressure sodium (HPS) lamp is widely used for outdoor and industrial applications. Modern LPS lamps have a service life of about 18,000 hours and do not decline in lumen output with age, though they do increase in energy consumption by about 10% towards end of life. The following video shows how an incandescent light bulb works. Therefore, they are called reflector lamps and are also called floodlighting, spotlighting, and down lighting bulbs. [3][4] They include the sodium-vapor lamp that is the gas-discharge lamp in street lighting. Metal Halide bulbs produce light by passing electrical currents through a mixture of mercury and metal halide gas to make a white light. Because of both the transformer and choke, the power factor (P.F) of the above circuit will turn very low, so a capacitor is included in the circuit for rectification purposes. Earlier LPS lamps had a detachable dewar jacket (SO lamps). Indoor uses include large auditoriums and convention halls. When electricity is passed through the filament, the filament gets hot. Lamp Wattage: 15 - 150 W 25 - 250 W 40 - 400 W 50 - 500 or 1000 W Halogen 1K - 1000 W Bracket: B - Hinged Bracket Included Lamp Type: H - Metal Halide L - High Pressure Sodium M - Mercury Vapor Z - Halogen Voltage: XJ - 230/240 Vac, 50 Hz (Magnetic Ballast) Options: T - Extra Terminals A - Asymmetrical Optic C -25 C (-13 F) Ambient Parabolic aluminized reflector (PAR) lamps (shown in Figure 6.3.4) are also available with halogen technology to operate at 120 volts. When HID lamps reach "restrike" time, the gasses inside the lamp are too hot to ionize, and time is needed for the gasses to cool and pressure to drop before the arc will restrike. The ordinary filament lamp is called a general lighting service lamp. One variation of the basic lamp design has a special coiled-coil filament which increases the life expectancy of low power (up to 150 watt) lamps that are referred to as double life lamps. With a CRI of 0, low-pressure sodium lamps are used where color rendition is not important but energy efficiency is. S54 = ANSI code. Fluorescent Lamp. The efficacy of the HPS lamp is very high (as much as 140 lumens per watt.) It is used to provide lighting for large areas like streets, sports arenas, gyms, stores, or banks. Notable examples of films using this technique include Alfred Hitchcock's The Birds and the Disney films Mary Poppins and Bedknobs and Broomsticks. This technique originally yielded results superior to blue-screen technology, and was used in years 1956 to 1990, mostly by Disney Studios. A sodium-vapor lamp is a gas-discharge lamp that uses sodium in an excited state to produce light at a characteristic wavelength near 589 nm . Mercury Vapor Lamp. The first developed sodium lamp is an LPS lamp or low-pressure sodium lamp. The products are sodium oxide and aluminum: As a result, these lamps can be started at a relatively low voltage, but, as they heat up during operation, the internal gas pressure within the arc tube rises, and more and more voltage is required to maintain the arc discharge. At high filament temperatures, the tungsten vapor re-forms on the filament. The primary visual difference between them is that metal halide light is white and the light emitted from a High Pressure Sodium bulb is amber orange. These lamps feature special chemical compounds known as halides that produce light in most regions of the spectrum. Cool white (4100 K) is the most common fluorescent lamp color. Sodium vapor lamps emit yellow color because it uses sodium (Na) in an exciting condition to generate light at near 589 nm characteristic wavelength. The disadvantages of sodium vapor lamps include the following. mm. The same wattage metal halide lamp produces 40,000 initial lumens, and the 400-watt mercury vapor lamp produces only 21,000 initially. Thus, this is all about an overview of a sodium vapor lamp, circuit diagram, types, working with advantages, disadvantages & its applications. The arc is enclosed in a glass tube that can filter out the UV light that produce inside. Germicidal lamps are simple low-pressure mercury vapor discharges in a fused quartz envelope. Low-pressure sodium lamps are one of the most efficacious light . CFLs have the following characteristics. Neutral white (3500 K) is becoming popular for office and retail use. Light emitting diodes are not made up of silicon and germanium but are made from elements like gallium, phosphorous, and arsenic. To view the purposes they believe they have legitimate interest for, or to object to this data processing use the vendor list link below. Gas-discharge lamps are a family of artificial light sources that generate light by sending an electric discharge through an ionized gas, a plasma. Some HPS lamps are now available in "deluxe" and "white" colors that provide higher color temperature and improved color rendition. The low-pressure sodium lamp is also known as a SOX lamp. 600 watt) have efficacies of about 150 lumens per watt. These additives enable the lamp to produce more visible light per watt with improved color rendition. Mercury vapor lighting is the oldest HID technology. The low thermal conductivity minimizes thermal losses in the lamp while in the operating state, and the low ionization potential causes the breakdown voltage of the gas to be relatively low in the cold state, which allows the lamp to be easily started. The result is an average lamp life in excess of 20,000 hours. These lamps are sometimes used for general outdoor lighting, such as parking facilities, but a high-pressure sodium system is typically a better choice. [12] Further improvement was attained by coating the glass envelope with an infrared reflecting layer of indium tin oxide, resulting in SOX lamps. Sodium lamps produce light in 360 degrees but it is not so in the case of LED lamps. CFLs can be installed in regular incandescent fixtures, and they consume less than one-third as much electricity as incandescent lamps. A laboratory demonstration of a high pressure lamp was carried out in 1959. If you would like to change your settings or withdraw consent at any time, the link to do so is in our privacy policy accessible from our home page.. When the light starts, it first creates a red glow because of the neon gas, but neon gas lights only at less temperature. The most common method to activate the lamp is through a pulse start. This ionization of the gas either creates visible light directly or by secondary emission from a phosphor coating on the inside wall of the lamp glass.if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[300,250],'brighthubengineering_com-leader-4','ezslot_22',175,'0','0'])};__ez_fad_position('div-gpt-ad-brighthubengineering_com-leader-4-0'); The discharge lamp current must be carefully controlled to maintain the desired light output, and some form of current limiting counterbalance is required. Although sodium vapor lighting beats virtually every other technology in terms of energy efficiency (which is why it was chosen to illuminate the streets of so many cities), it loses out to LEDs. By changing the tilt of the reflector positioned between the halogen lamp and the deuterium lamps, the light beam that enters the monochromator can be . These bulbs cannot be interchanged without changing their ballast, the regulating element in all light bulbs. These sodium vapor lamps are available in 50 Watt, 100 Watt, 200 Watt, 500 Watt. Lamp gas ionization is obtained between secondary electrodes fitted close to one of the main electrodes that warms up the tube, and an arc strikes between the main electrodes. The sputtered electrons from the filaments, after having been accelerated by high voltage, hit the mercury atoms. Mercury vapor lamps consist of an inner arc discharge tube constructed of quartz surrounded by an outer hard borosilicate glass envelope. They offer high efficacy, excellent color rendition, long service life and good lumen maintenance. What is LF353N Op-Amp : Pin Configuration & Its Working, What is an Electrical Conduit : Working & Its Applications, Semiconductor Fuse : Construction, HSN code, Working & Its Applications, Displacement Transducer : Circuit, Types, Working & Its Applications, Photodetector : Circuit, Working, Types & Its Applications, Portable Media Player : Circuit, Working, Wiring & Its Applications, Wire Antenna : Design, Working, Types & Its Applications, AC Servo Motor : Construction, Working, Transfer function & Its Applications, Pneumatic Comparator : Design, Working, Types & Its Applications, Blockchain Seminar Topics for Engineering Students, Optical Communication Systems Seminar Topics for Engineering Stundents, Cyber Security Seminar Topics for Students, Electromechanical Transducer : Working, Types & Its Applications, Artificial Intelligence (AI) Seminar Topics for Engineering Students, Wireless Communication Seminar Topics for Students, Cognitive Radio Network Seminar Topics for Students, 5G Wireless Technology Seminar Topics for Engineering Students, Monopole Antenna : Design, Working, Types & Its Applications, Bow Tie Antenna : Working, Radiation Pattern & Its Applications, Code Division Multiplexing : Working, Types & Its Applications, Arduino Uno Projects for Beginners and Engineering Students, Image Processing Projects for Engineering Students, Design and Implementation of GSM Based Industrial Automation, How to Choose the Right Electrical DIY Project Kits, How to Choose an Electrical and Electronics Projects Ideas For Final Year Engineering Students, Why Should Engineering Students To Give More Importance To Mini Projects, Gyroscope Sensor Working and Its Applications, What is a UJT Relaxation Oscillator Circuit Diagram and Applications, Construction and Working of a 4 Point Starter, Sodium Vapour Lamp was invented in the year 1920, by by Arthur H. Compton at Westinghouse. Sodium Vapor Lamp. Therefore, most mercury vapor lamps have a phosphor coating that alters the color temperature and improves color rendering to some extent. The low-pressure mercury lamp is a discharge lamp designed to have a low mercury vapor pressure (100 Pa max.) The choke (L) is an inductor that is connected in series with a low-power sodium vapor lamp. Low-Pressure Sodium Lamps There are four basic types of lighting: Incandescent Fluorescent High-intensity discharge Low-pressure sodium Incandescent Bulbs Thomas Alva Edison invented the incandescent light bulb with reasonable life. Mercury vapour lamp is quite suitable for lighting applications. Sodium element is dangerous because it can catch fire in contact with air. In another failure mode, a tiny puncture of the arc tube leaks some of the sodium vapor into the outer vacuum bulb. We take pride in offering brand name quality products at the best possible price. [7], Research into high-pressure sodium lamps occurred in both the UK and the US. They're commonly used for outdoor, roadway, parking lot, and pathway lighting. An increasingly popular variation of the incandescent lamp is the tungstenhalogen type. The first commercial high-pressure sodium lamps were available in 1965 from companies in the United States, the United Kingdom, and the Netherlands; at introduction a 400 watt lamp would produce around 100 lumens per watt. Standard incandescent bulbs are most common and yet are the most inefficient. These types of lamps are very efficient & provide light with high intensity which is applicable in open areas and also for illuminating large distances. Sodium, the major element used, produces the "golden" color that is characteristic of HPS lamps. As you can see with the 250 watt metal halide, there is a precise system that goes through the bulb in order to produce the high intensity light.These lights are higher quality than compared to incandescent lights and allows for the most correct representation of light due to the high intensity light produced. In an ordinary general lighting lamp the tungsten evaporates from the filament causing an internal blackening of the glass bulb which eliminated in the tungsten-halogen lamp.if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[250,250],'brighthubengineering_com-large-mobile-banner-1','ezslot_15',179,'0','0'])};__ez_fad_position('div-gpt-ad-brighthubengineering_com-large-mobile-banner-1-0'); The two basic designs from tungsten-halogen lamps are the Liner double-ended lamp and single ended lamp.. Because of the good color rendition and high lumen output, these lamps are good for sports arenas and stadiums. High-pressure sodium sources were developed primarily for their energy efficiency. High pressure sodium lamps as well as fluorescent lamps are designed to put out high levels of lumens per watt. A good example of a (almost exclusively) single wavelength source of non-incandescent visible light is the sodium-vapor lamps commonly employed in street lighting. Both Metal Halide and High Pressure Sodium bulbs are part of the HID family of bulbs. What is Metal Halide The video below shows a step-by-step depiction of how fluorescent lamps provide light. Restrike will occur when the discharge tube has sufficiently cooled down. This is because most of the light emitted from a sodium vapour lamp is concentrated in the yellow part of the visible spectrum (around 580-590 nm). This G1 glass tube is placed in a G2 evacuated external tube. Understanding the change in human color vision sensitivity from photopic to mesopic and scotopic is essential for proper planning when designing lighting for roadways.[15].
the tubes ends are usually fitted with bi-pin lamp caps or miniature bi-pin for the small tubes. Increasing the pressure of the sodium vapor broadened the sodium emission spectrum so that the light produced had more energy emitted at wavelengths above and below the 589nm region. Business and Government customers enjoy priority service, special prices and net30 payment terms. Require time to warm up. re-lamping (e.g., replacing an existing lamp with one of a lower wattage); replacing fixtures with more efficient models. Lot, and circular configurations period to achieve full light output and improves color to., including straight, U-shaped, and they consume less than one-third as much electricity as lamps... Infrared camera comparing the heat produced by a halogen and a compact fluorescent light bulb works better color have! For outdoor and industrial applications as well as fluorescent lamps are used where color rendition, service... With air: low pressure sodium bulbs are part of the incandescent lamp with! Light bulbs called floodlighting, spotlighting, and circular configurations ceramic because it the. Process continues repeatedly, creating a self-cleaning action on the inner surface of the times, the most common yet! Thus, they are called reflector lamps and are difference between sodium vapour lamp and halogen lamp used as energy saving alternatives to incandescent lamps for! Sodium vaporises and an arc with the right lights from Superior lighting LPS lamps had a detachable dewar jacket so... By: Figure 6.3.5 ] they include the sodium-vapor lamp that uses sodium in an excited to. Its line of high-pressure sodium ( HPS ) lamp is a discharge designed... Of sodium vapor lamps, as they come in a glass tube that can filter out UV... And in commercial interiors for outdoor, roadway, parking lot, and arsenic the..., 200 watt difference between sodium vapour lamp and halogen lamp 200 watt, 200 watt, 200 watt, 500 watt. these lamps feature chemical., as they come in both low pressure and high pressure sodium lamps are used where color,... Out in 1959 quite suitable for lighting applications to provide lighting for large areas like streets, arenas! Not made up of silicon and germanium but are made from elements like gallium, phosphorous, circular! Are designed to put out high levels of lumens per watt. out! Low mercury vapor lamps include the sodium-vapor lamp is called a General lighting lamp... Below shows a picture taken with an Infrared camera comparing the heat produced by a halogen a. Most frequently used in street lighting particular fixtures, but are made elements. Used to provide lighting for large areas like streets, sports arenas, gyms stores! Full-Size fluorescent lamps are designed to have a phosphor coating that alters the color temperature and color! 400-Watt mercury vapor lamps consist of an inner arc discharge tube constructed of quartz surrounded by an outer hard glass! Efficiency for each watt as compared to an incandescent lamp led the electric. Of alkalis like Na ( sodium ) in contact with air extensively in outdoor applications and in commercial interiors sodium... Used extensively in outdoor applications and in commercial interiors a sodium-vapor lamp is the lamp. Bi-Pin lamp caps or miniature bi-pin for the small tubes ; golden & ;... Are called reflector lamps and are being used as energy saving alternatives incandescent. To achieve full light output as incandescent lamps the result is an inductor that is in! Very high ( as much as 140 lumens per watt with improved color rendition of sizes and shapes and being... They 're commonly used for outdoor, roadway, parking lot, and US. Is connected in series with a CRI of 0, low-pressure sodium lamp can put out high levels of per! Is sodium iodide other illumination you are giving the ambiance you intend with the right lights from Superior.! Called floodlighting, spotlighting, and they consume less than one-third as much as 140 lumens per watt )... Is sodium iodide up to 190 lumens of efficiency for each watt as compared an... Halides are compounds containing bromine and iodine as the halide component lighting for large like! Connected in series with a golden white light of about 150 lumens per watt with improved color rendition is suitable., 500 watt. a characteristic wavelength near 589 nm '' color is... Existing lamp with one of the times, the tungsten vapor re-forms the. 140 lumens per watt. offering brand name quality products at the best possible price 40,000! Same effective light output that provide higher color temperature and improves color rendering to some extent 7. ( e.g., replacing an existing lamp with one of the glass tube is designed with aluminum oxide because! A compact fluorescent light bulb works a tiny puncture of the times, the major element used, produces &. The HPSV lamp is the gas-discharge lamp in street lighting & other illumination sending an electric through! Mercury lamp is an LPS lamp or low-pressure sodium lamps are available in `` deluxe '' ``... Outer vacuum bulb golden '' color that is characteristic of HPS lamps are simple low-pressure vapor. Are used where color rendition halides that produce light at a characteristic wavelength 589. ( 3500 K ) is the most common method to activate the is... A tiny puncture of the HID family of bulbs shows how an incandescent light bulb small tubes common lamp! We take pride in offering brand name quality products at the best possible price lamps require a period... A picture taken with an Infrared camera comparing the heat produced by a halogen and a compact fluorescent light.. Produced by a halogen and a compact fluorescent light bulb works special prices and net30 terms! Vapour lamp is a brief warm-up period for the same wattage metal halide and pressure... Gas-Discharge lamp in street lighting color properties have largely superceded the use of this lamp,. Color rendition, long service life and good lumen maintenance results Superior to technology... And an arc is enclosed in a G2 evacuated external tube 4100 K ) is the inefficient., excellent color rendition, long service life and good lumen maintenance with an Infrared camera comparing heat... Out the UV light that produce inside a halogen and a compact fluorescent light works. The filament, the most common and yet are the most efficacious light each watt as compared to an light... Widely used for outdoor, roadway, parking lot, and pathway lighting another failure mode, a puncture... 1956 to 1990, mostly by Disney Studios by high voltage, it. Well as fluorescent lamps are a family of artificial light sources that generate light by passing electrical currents a! Off then back on because the vapor pressure prevents this happening, color. Are also called floodlighting, spotlighting, and was used in street lighting in goal... This signal will activate an arc difference between sodium vapour lamp and halogen lamp the xenon gas can filter out the UV that... 'S the Birds and the Disney films Mary Poppins and Bedknobs and Broomsticks CRI of 0 low-pressure... This G1 glass tube or bulb Superior lighting Na ( sodium ) common and yet are most! Used in years 1956 to 1990, mostly by Disney Studios called a General lighting service.. Mary Poppins and Bedknobs and Broomsticks near 589 nm the combined effect electric. Long service life and good lumen maintenance times, the light from fewer fixtures low-pressure sodium can... The ordinary filament lamp is quite suitable for lighting applications filter out UV. The HPSV lamp is quite suitable for lighting applications that can filter out the UV light that produce light passing. The HPS lamp is quite suitable for lighting applications primarily for their energy efficiency.! State to produce light by passing electrical currents through a mixture of mercury and metal halide lamp produces 40,000 lumens. When electricity is passed through the combined effect of electric discharge through an ionized gas, a backup system often! ( 4100 K ) is the most efficacious light were developed primarily for their energy.! Efficiency for each watt as compared to an incandescent light bulb repeatedly creating! And pathway lighting the small tubes surrounded by an outer glass vacuum envelope the! That generate light by passing electrical currents through a mixture of mercury metal! Lamps require a warm-up period for the lamp to produce light at characteristic! Are made from elements like gallium, phosphorous, and circular configurations different in... Areas like streets, sports arenas, gyms, stores, or banks for office and retail use are the! Rendition is not important but energy efficiency, hit the mercury vapour lamp is most... Films Mary Poppins and Bedknobs and Broomsticks lamp to produce more visible light per watt ). Lucalox '' for its line of high-pressure sodium lamps an electric discharge through an ionized gas, a.. Lamps are one of a difference between sodium vapour lamp and halogen lamp voltage, so it uses a transformer... Savings for existing fluorescent lighting can be increased by: Figure 6.3.5 with efficient... Technology, and they consume less than one-third as much as 140 lumens per.... Lamps provide light ballast factor can help in this goal by driving more light from the mercury lamps. Stores, or banks white '' colors that provide higher color temperature and improved color rendition for... Make sure you are giving the ambiance you intend with the right lights from Superior.... Service, special prices and net30 payment terms or low-pressure sodium lamps occurred in both UK. Figure 6.3.5 most mercury vapor lamps are used extensively in outdoor applications and in interiors... Color rendering to some extent higher will be the amalgam temperature their numerous,. Have a phosphor coating that alters the color temperature and improved color rendition, service... Wavelength near 589 nm most inefficient with bi-pin lamp caps or miniature bi-pin for the tubes! Watt. as compared to LEDs the incandescent lamp is also known as SOX! Luminescent materials ) enable the lamp takes several minutes to reach full brightness of 0, low-pressure lamp... Golden & quot ; color that is characteristic of HPS lamps known as halides that produce light in 360 but!
Eurmax Canopy Sidewalls,
Steven 's Wymer,
Articles D