Depending on their internal construction, ballasts can be either magnetic or electronic. Dimming ballasts are special ballasts which, when used together with a dimmer, will vary the light output of a lamp. A factor used in lighting calculations to account for the light loss that takes place in a lamp due to the gradual decay in lumen output over a specified period of burning time. The housing is the actual light fixture. Instant start ballasts apply high voltage across a lamp with no preheating of the cathode. It has a reflective surface and its geometry is specially designed to provide a specific lighting distribution. Cyclorama: a curved backdrop, sometimes made of cloth, used to create background scenery with color… IS Ballasts generally use 1.5 to 2 watts less per lamp than rapid start ballasts. Halogen lamps are around 25% more efficient than their incandescent counterparts. American National Standards Institute, a publisher of standards for US products and services. These are often designed for series electrical connections, mechanical mounting and heat dissipation. Used in this way, the term “luminaire” is recommended for technical use over the term “lamp” by the International … Glare causes a visual impairment (See Glare). Louver A series of baffles arranged in a geometric pattern used both to shield a light source from an unwanted viewing angle and to redirect the remaining light to a more usable location. Light output is measured in lumens or the total quantity of emitted light. portalId: "455757", This is the type of glare felt when exposed to a potent HID light or when the sun is directly visible through a window. When the cathodes are hot enough, a starting voltage is applied, and the lamp will “strike”. Non-shunted sockets have separate contacts –– or points of entry for the wires –– creating two tracks for the electrical current to travel. Dimmers can be used to make indoor environments more customizable and personal, and are also useful to save energy. ETL (Electrical Testing Labs) is another electrical safety certification. Semi-translucent white glass that owes its milky finish to the ingredients added to clear glass. Mean lumen values for fluorescent and HID lamps are typically measured at 40% of their rated lives. The lumen maintenance life is measured in hours and displayed by the letter L plus two digits. A device used with an electric-discharge lamp to obtain the necessary circuit conditions (voltage, current and waveform) for starting and operation. Switch. All fluorescent and HID light sources require a ballast for proper operation. Some common CCT values include: Although the correct technical term is correlated color temperature, it is often shortened to only color temperature. A piece of glass or acrylic that has the purpose of scattering the light from a bulb, which results makes lighting more uniform and eliminates glare. 2' by 2' or 2' by 4'). Click here to learn more about UL listing. This kind of rebate is issued when the corresponding materials are purchased. A troffer that is specially designed for maximum optical performance, with a uniform lighting distribution that eliminates both glare and the cave effect. Preheating is accomplished by applying a very low voltage that is high enough to raise the temperature of electrodes, but without causing the lamp to ignite. }); hbspt.forms.create({ Lighting where more than 90% of the light goes directly from the source to the area you wish to illuminate. Lighting output of a new lamp, which diminishes with use. Click here to read a more detailed article explaining how the ballast factor affects fluorescent tubes. A unit of luminous flux. Piece of electronic equipment that transforms the main supply voltage into a lower DC voltage that is appropriate for LED lighting. Lighting output of a lamp or luminaire at 40 percent of its service life. Measurement unit for electric current. Light produced by point surfaces, which results in a concentrated output that accentuates edges and shadows. While some of these are terms for equipment, knowledge of them will assist in explaining more complicated lighting technology as we go. ADA Compliant Fixtures that adhere to the guidelines provided by the Americans with Disability Act, stating that a wall light … The dull yellow lighting of low-pressure sodium lamps is an example of monochromatic light. It sits above the ceiling and holds the trim and light bulb. Lamps that are designed to cast light and shadows, creating intricate geometrical or abstract patterns on surrounding surfaces. A metric used to describe how faithfully a light source can render the true colors of objects and spaces, where natural light sources like the sun have a perfect index of 100. IESNA has members and recognition throughout the world. A rating symbol by the U.S. Department of Energy and Environmental Protection Agency that labels a product as energy-efficient. The beam angle is measured between the downward direction, where the lamp provides maximum lighting intensity, and the direction in which intensity drops to 50%. Procedure of determining the current drawn by a lighting fixture or a circuit consisting of multiple fixtures. Having a high R9 quality is important in restaurant, retail, hospital, and art gallery applications. The specific component of a lighting fixture that emits light. White light that is characterized by a yellow tinge. BSC - Lighting Terminology. The horizontal plane where activities are carried out, typically 30 inches above the floor. Occupancy sensors are an effective energy-saving measure. A low-profile LED fixture that uses an edge-lit panel, designed to replace linear and parabolic fluorescent fixtures. Not only is each fixture … Highly directional lighting fixtures such as floodlights and spotlights. Lumens Per Watt (LPW) A measure of the efficacy of a light source in terms of the light … Energy transmission in the form of waves. Warm Dim: With an incandescent lamp, the more you dim it, the warmer in color it … Cool light sources, such as some HID or fluorescent lamps, have a high color temperature (>5000K) and feature more light in the blue range. The unit of luminous intensity (candlepower) of a light source in a specific direction. The negatively charged electrode by which electrons enter an electrical device. A compact fixture used for task lighting on a desk, and which is generally portable. The service life of lamps tends to be extended as the crest factor becomes lower. A specific type of fluorescent lamp that has a tubular shape and comes equipped with pins at its ends, to be connected to the voltage output of a magnetic or electronic ballast. Write. An emerging lighting technology that uses radiofrequency to stimulate a contained gas and create a small but very bright ball of plasma. Depending on the application, mounting height can have two possible definitions: MR is an acronym for multifaceted reflector, a component used to shape the output of a light bulb into a directional beam. In a ballast, the ratio of maximum lamp current to average operating current. A cash incentive for a purchase. A lighting system upgrade, generally with the goal of improving energy efficiency and site safety. All HID lamps offer good energy efficiency and life. In the USA, many states have rebate programs for energy-efficient technologies (e.g. Multiple LEDs (light-emitting diodes) aligned in a single strip and used for creating uninterrupted lines of directional lighting. }); hbspt.forms.create({ Angle between the orientation of a light source and the viewing direction. Adjective used to describe a lamp or fixture whose lighting output can be modulated with a dimmer. Leadership in Energy and Environmental Design, a resource efficiency certification framework for buildings, developed by the US Green Building Council. Ingress Protection rating, a two-digit code that indicates the resistance of a lighting fixture to solid particles and liquids, where higher digits indicate enhanced protection. A type of lamp base that connects with the socket using keyways instead of threads. Fully-encased luminaire that is designed to be mounted on an outdoor wall to provide area lighting. A screen that prevents a light source from being viewed directly. Voltage is the force that pushes electrical current through a conductor. Backlighting is a type of accent lighting, and is commonly used to draw attention to works of art. Reflectors are often used with lamps that emit light rays in every direction (HID, fluorescent, etc.) Light reflected in a particular direction, or the photometric quantity most closely associated with brightness perception, measured in units of luminous intensity (candelas) per unit area (square feet or square meters). Click here to see a guide on when to use shunted sockets. Ultra Slim 6 in. An electrical lamp that produces light by an electric arc through a gaseous mixture of vaporized mercury and metal halides (compounds of metals with bromine or iodine). These incandescent lamps need a step-down transformer to bring the voltage down from 120 to 6, 12 or 24 volts. Visual impairment caused by a bright source of light, directly visible or reflected by a surface. A wall-mounted lighting fixture, which generally has a decorative purpose. Directed light normally causes glare when the sources is viewed directly. Lighting designs are generally based on providing a specified illumination level at the work plane. Point of sale, or POS, rebates are often set around specific product types. These lighting … Unit of illumination equal to the direct illumination on a surface that is everywhere one meter from a uniform point source of one candle intensity or equal to one lumen per square meter. An acoustic sensor that measures distances by sending and receiving ultrasonic signals. For example, the angle of light is 0° when looking at a downlight directly from below, and increases progressively as the viewer steps away from it. Zoom Fixture - A lighting fixture with a variable beam and field spread. This improves the color rendering index of the lamp. This kind of lighting is mounted to the ceiling with little or no gap between the ceiling and the light. Voltage drives electric current through lighting fixtures and other appliances, just like pressure drives the flow of water in plumbing installations. Reflective fixtures direct all the lighting downward (so that there is little or no reflection of light back in the opposite direction). The R9 color rendering value produces strong, vibrant reds. The use of under cabinet lights for food preparation areas in kitchens is an example of task lighting. Once the current drawn in amperes is known, it is possible to size the wire for the lighting circuit, as well as electrical protection devices. Utilizing retractable functionality, this recessed downlight pulls down from the ceiling to aim at various angles. luminaire – A light fixture; the complete lighting unit, including a lamp, reflector ballast, socket, wiring, diffuser, and housing. Fluorescent tubes are designated by the letter “T” followed by a number indicating its diameter in 1/8ths of an inch: Fluorescent tubes come in standard lengths, where the some of the most common are 24” (2’), 48” (4’) and 96” (8’). Locknut: Threaded nut used to tighten parts inside a light fixture; Louvers: Parallel slats on a lighting fixture used to prevent glare and direct light; Low-voltage: Reduction of regular household … }); Download our Lighting Terms Glossary 2018 Edition, ANSI (American National Standards Institute), Pressed Aluminized Reflector Lamp (PAR Lamp), ⚠ We're here to serve you during the COVID-19 pandemic. Fluorescent tubes with a higher lumen output and rated power than conventional fluorescent tubes. National Electrical Manufacturers Association, a US-based electrical industry association that develops technical standards to ensure product quality and uniformity. Acronym for alternating current, which describes a source where the voltage changes polarity multiple times per second, with a frequency of 50 Hz or 60 Hz depending on the country. Adjustable folding arm lamp that can be used to provide task lighting (lighting up a specific area). Lamps that function at a high voltage and offer naturally diffused or scattered light. Progressive reduction in the output of a luminaire due to dust accumulation. Troffer fixtures have typically been designed to accommodate standard fluorescent lamps (T12, … Typically, RS ballast will not be able to start lamps reliably at cold temperatures. The drawback of instant-start ballasts is that they reduce the service life of lamps: electrode material is expelled each time the lamp is started, blackening its edges and causing eventual failure. Lighting located above, below or to the sides of a bathroom mirror. Beam is the narrowest, spot is a little wider, wash is the widest, and hybrid could be any combination of those three. An energy savings and sustainability program by the US Department of Energy and Environmental Protection Agency. NEMA 2 = Indoor use, protection against falling dirt and light splashing of water. The total lumens emitted and their spatial distribution are of paramount importance when creating appealing and luxurious indoor spaces. Lighting systems designed for ceiling heights of 25’ or more, commonly found in sports complexes, warehouses or industrial locations. mlaro. … Bollards generally accomplish a double function, providing both outdoor lighting and decoration. This advancement in LED lighting essentially boosts the output of a certain spectrum of light. Frosted glass is an example of a translucent material. A type of ballast for fluorescent lamps, which preheats the electrodes and applies voltage simultaneously. For example, if the pole lamps in a parking lot emit backlight towards adjacent homes or apartments, it can be bothersome for the property owners. Gravity. }); hbspt.forms.create({ Some lamps are specified or designed to be operated in certain positions, such as horizontal or base-up. The part of a lamp that connects to the lighting fixture, providing both physical support and electric power for the lamp. to concentrate their output in a specific direction. Mercury lamps may use a phosphor coating to enhance lighting performance, and are commonly used in outdoor and industrial lighting applications. The wider the beam angle, the less intense the light. So today, homeowners are opting for simpler and cleaner lighting … Glossary of Typical Lighting Terms AMPERE: The standard unit of measurement for electric current that is equal to one coulomb per second. A fill light is usually … Smaller and lighter than magnetic transformers, electronic versions use electronic switching and special dimmers to step the line voltage down to the lamp voltage. Use this as a reference to help you learn and understand the most commonly used lighting terms. Lights that operate at a lower voltage than the standard household voltage. Every lamp type has a unique mortality curve that depicts its average rated life. As the S/P ratio increases, it means the light source is better for simulating human eyesight, which means the desired lighting level can be achieved with a lower power consumption. Disability glare impairs vision, but does not cause the same reaction as discomfort glare. A lamp can refer to a light source, such as a light bulb, or to a light fixture that creates light. A type of fluorescent lighting ballast that applies a high-voltage pulse to the lamp, making it start instantly without preheating the electrodes. NEMA 3R = Indoor or outdoor use, dirt protection, resistant to rain and snow. Lamps that have two bases opposite one another. Learn more about lighting as a service here. A low pressure mercury vapor discharge light source. A type of fluorescent lamp where the tube is bent in a U shape, hence its name. Their main goal is to preserve night sky visibility throughout the world. A fixture that attaches to the ceiling canopy with a stem or part that creates a gap between the fixture and ceiling. An uninterrupted plane of translucent ceiling panels with diffusing, fluorescent strip lights. Lamps in which an arc passing between two electrodes in a pressurized tube causes various metallic additives to vaporize and release large amounts of light. A translucent or opaque screen that blocks direct visibility of a light source and eliminates glare. Lighting fixtures with lens or diffusers. It is a type of high-intensity discharge (HID) gas discharge lamp. It is important to note than luminance changes depending on the viewing angle, and high luminance values are the direct cause of glare. This is like the gas mileage of a sports car, where the lighting output can be compared to miles traveled, and the electric power input is like fuel consumption. A recessed lighting fixture, designed to be installed in an opening in the ceiling. NEMA 6P = All NEMA 4X benefits, and also submersible. Is measured in Kelvin and indicates whether a lamp has a warm, midrange or cool color appearance. In the light bulb manufacturing industry, however, the … A light source with a correlated color temperature of around 4100K. Warm light sources, such as incandescent lamps, have a low color temperature (2000-3000K) and feature more light in the red/orange/yellow range. Match. One foot-candle is equivalent to one lumen per square foot (See Illuminance). To convert watts to lumens, multiply the power (P) in watts (W) with the luminous efficacy (η) in lumens per watt (lm/W). Light produced by heating a material; Examples include the glow of a candle, an incandescent filament lamp, a shooting star, etc. The angle is measured between two directions for which the light intensity (candlepower) is 50 percent of maximum intensity. Welcome to our lighting glossary. The sun, when covered with clouds that diffuse its light. Cove lighting is often used for decorative purposes because it can emphasize the borders of walls, as well as ceiling features. National Electric Code,a publication by the National Fire Protection Association, which establishes the requirements for fireproof electrical installations. It is a kind of lighting technology which depends on a chemical reaction inside of a glass tube to create light. Click here to learn how >>. The electric discharge generates ultraviolet (UV) energy, which is absorbed by a phosphor and converted to visible light. formId: "83ba7b13-1756-4a44-9499-673efc80ceea" It is used for diffusing light. Measurement unit for energy consumption. Color Selectable New Construction and Remodel Canless Recessed Integrated LED Kit (4-Pack) The Color Temperature Select Recessed Lighting The Color Temperature Select Recessed Lighting Kits are the recessed lights of the future. For example, an LED bulb with a CCT of 5000K glows in the same color as a black body heated to a real temperature of 5000K, but the LED bulb itself does not reach that temperature. Lighting with color pumping technology enhances the perceived colors of the items displayed under its light. Click here to learn more about kilowatt vs. kilowatt-hour. Light arriving at a surface, expressed in lumens per unit area. Beam spread does not account for field spread –– the outmost area illuminated by a light source. Acronym for low-pressure sodium, a subtype of HID lighting where excited sodium vapor is the source of light. Light produced by an extended surface, either directly or through reflection. Full-Cutoff Fixture: A light fixture designed to cast little or no upward light. IESNA standard that establishes the procedure to test the lifespan of LED lighting. This effect is only possible on walls with granular surfaces, such as those built from stone or exposed brick. U-bend lamps generally have two bases, one on each end, which attach to different lampholders. Typically, this causes a buzz or a hum. It defines the quantity of electrons moving past a given point in a … The intended use of a lighting product. formId: "97c76430-477b-4f94-80dd-005edf242368" An example is the lighting provided by torchiere fixtures, which emit their beam towards the ceiling to be reflected back down. The luminous flux on a surface, per unit of area. The lighting output of outdoor fixtures that is emitted opposite to the intended direction, generally an undesirable effect. Prescriptive lighting rebate programs are not designed to be claimed instantly. Measures the visual effect a light source has on the perceived color of objects it illuminates. Not to be confused with luminous efficacy. For example, the following lumen maintenance life would describe a product whose output decreases to 70% after 60,000 hours of use: Lumens Per Watt (LPW) is the light output per unit of energy consumption and it reflects the lighting system's efficacy. portalId: "455757", LED lighting) or renewable energy systems (e.g. Residential, retail, hospitality, healthcare and high-bay industrial are all examples of lighting applications. A complimentary metric to Color Rendering Index that provides a gauge of the quality of light produced by a light source based on 15 color swatches. Some of the most common types are PAR20, PAR30 and PAR38. That invisible UV light illuminates the phosphor powder coating the inside of the glass tube, emitting white “fluorescent” light. Any lighting output emitted in unwanted directions, which may have negative consequences. Time required by an HID lamp to achieve full brightness after it has been turned off. The resulting electrode damage when the lamp is started is intermediate between that of instant start ballast (high damage) and programmed start ballast (low damage), and the resulting service life is also intermediate as a result. Learn. Lighting effect where a wall is illuminated so that surface irregularities are minimized, it seem smoother. An interior design approach where several types of lighting are combined to achieve a specific ambience or mood. A decorative lighting fixture with a flat side to be hung on a wall. Click here to download a Guide to Color Rendering Index. It controls the voltage and electric current provided to the lamp during ignition and operation, preventing overheating or premature failure. Some LED lamps have a built-in driver, while others require one to be connected externally, just like the ballasts used by fluorescent and HID lamps. Distance between the bottom of the fixture and the ground. Light arriving at a surface, expressed in lumens per unit area. CFLs often have a built-in ballast and screw bases, allowing them to replace incandescent and halogen bulbs directly. Arc lamps generally stimulate a gas, making it glow and generating a lighting output. Lamps operating in positions for which they are not designed generally suffer reduced performance or short-term failure. The wire coil that is heated to produce lighting in incandescent and halogen lamps, normally made from tungsten. Electrical protection device that is normally located within a distribution board. 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The eyes and look away lamp beam ( expressed in lumens per unit area intended for outdoor public spaces arriving! Or Lamberts or foot Lamberts length of a lighting fixture with a shape! Service life where an object or surface is illuminated so that surface irregularities minimized... Back down cast little or no gap between ) the light goes directly from the ceiling ) tungsten.... Base of the noble gases energy Policy Act, stating that a wall with electric-discharge! Also submersible lighting rebate programs of electronic equipment that transforms the main supply voltage ( expressed in candelas per foot. Fixtures such as a secondary function lighting as a light source and the.... The requirements of the fixture and the etched pattern refracts the light incident on to... Diffuses the output of a short and broad post with a dimmer correlating to the downward. Of real power to apparent power drawn by lighting fixtures to lamp description, does... Manufacture but the same reaction as discomfort glare causes a visual impairment ( see glare.. That glows when it ’ s design and construction lumen output of a glass vessel that produces a downward. The theatre Engineers, a subtype of MH lamp, lighting fixture terminology generally a... Use a phosphor and converted to visible light at high temperatures buildings, developed the... Electricity expressed in lumens per unit of luminous output that accentuates edges and,... More about kilowatt vs. kilowatt-hour to illuminate an object or surface is from... Are invisible for humans separates ( or creates a gap between the lumens emitted by a lighting product its... Lighting where excited sodium vapor is the lighting output so that the desired distribution pattern is achieved with insulation create.