Know Your Lighting ABC’s … continued
From Accent to Zone lighting, we’d like to clarify some common ~ and not so common ~ lighting terms you may hear as you build or renovate your home!
Hall / Foyer Fixtures: Can create a welcoming atmosphere, while providing you with general ambient lighting. Use ceiling, chain-hung or close to ceiling flush-mount fixtures for lighting in hallways, stairways and entrance halls.
Halogen Lamp: Incandescent lamp with halogen gas fill and a quartz glass capsule. The quartz capsule requires a separate glass shield or enclosure. Due to the halogen cycle, halogen lamps operate at higher internal temperatures, producing more lumens per watt and brighter light than ordinary incandescent; lamp life is also extended. Halogen lamps include A, MB, T, PAR and MR types.
Hammered Glass: Glass seen most commonly on outdoor fixtures that has a rippled, pitted “hammered” antique look.
Hand-Blown Glass: Individually produced glass made by artisans who blow molten glass into different decorative shapes.
Harp: Used to attach a shade onto a lamp.
Hard-Back: A shade that is lined with plastic.
Heat Ratings: Like recessed downlights, surface mounted fixtures must pass heat tests to assure they do not affect combustible ceiling materials. This limits the maximum wattage in these fixtures, and sometimes necessitates the installation of high-temperature wiring. Always follow the labeled lamping; never use higher wattages or different lamps.
HID: Abbreviation for high intensity discharge. Generic term describing mercury vapor, metal halide, high pressure sodium, and (informally) low pressure sodium light sources and luminaires.
High-Bay: Pertains to the type of lighting in an industrial application where the ceiling is 20 feet or higher. Also describes the application itself.
High Output (HO): A lamp or ballast designed to operate at higher currents (800 mA) and produce more light.
High Pressure Sodium Lamp: A high intensity discharge (HID) lamp whose light is produced by radiation from sodium vapor (and mercury).
Housing: Main body of a ceiling fan that connects the motor and other components.
Hurricane Lamp: A lamp having a distinctive globe glass housing for its bulb. Patterned after 19th century oil and candlestick lamps.
Illuminance: A photometric term that quantifies light incident on a surface or plane. Illuminance is commonly called light level. It is expressed as lumens per square foot (footcandles), or lumens per square meter (lux).
In-Ground Uplights: These outdoor accent lights provide maximum concealment because the source is recessed into the ground. Both line and low voltage sources are available.
Incandescence: Light produced by heating material so it glows. Incandescent filament lamps, candle flames and glowing coals are all examples.
Incandescent Lamp: Produces light with a wire filament, which creates light as it is heated by electric current.
Indirect Lighting: Lighting that directs all or most light upward for ambient or general illumination; comfortable illumination with few shadows. Typical fixtures include uplight cans, fluorescent lighting aimed up, track lights aimed up and torchieres.
Inside Frosted Lamp: Incandescent A lamp with a light etching or sprayed on diffusing coating on the inside of the bulb. Designated as IF.
Insulated Ceiling Fixture: Recessed down-lighting suitable for direct burial in ceiling thermal insulation. Called Type IC.
Integrated Dimming Systems: A dimming switch that allows you to create multiple preset lighting scenes within a room. Scenes can be recalled at the touch of a button from a single wall box or with a hand held remote control.
Intelli-Touch: On ceiling fans, a two-wire computerized system with wall control convenience that gives independent control of lights and fan. It has a silent multi-speed operation for the fan and provides variable light intensity.
IR Lamp: Infrared-Reflecting Halogen Lamp. A special interior coating redirects infrared energy onto the filament, which increases output without added power.
Iron: A strong metal, iron imparts a natural quality to a lighting fixture. Wrought Iron is heated and hammered into shape, and can be formed into pleasingly fluid forms.
Jack: Plug-in stem used in low voltage fixtures.
Junction Box: Enclosure that protects spliced wires and supports surface fixtures, such as wall fixtures or ceiling fans. Also called an outlet box.
Kelvin: Scientific unit of temperature. Color temperature is measured on the Kelvin scale.
Kilowatt Hour: KWH. A unit of measurement for electrical energy. One kilowatt hour equals 1000 watts of energy used for one hour.
Lacquer: Clear coating that protects metal fixtures from rusting or tarnishing. May be tinted in various colors by adding colored dye.
Lamp: A portable lamp consists of a (from bottom to top) a stand, a base, a mount through which the electrical wiring travels, a neck, a socket to hold the bulb, a lamp shade, a harp that connects the top of the shade to the socket, and a decorative finial that holds the harp in place. Also refers to a light bulb.
Lamp Holder: Socket inside a housing, which holds the lamp in place and connects it to the electrical source.
Lamping: Equipping a fixture with a lamp.
Lanterns: Unlike chandeliers which are oriented radially, lanterns hang vertically, often with several tiers. Modern pendant lanterns use hanging glass panels or glass rods, often with beveled edges to reflect the light.
Lead Crystal: Fine quality glass having a high content of lead oxide.
Leaded Glass: Small pieces of glass joined at the edges with metal, traditionally lead.
LED: Light Emitting Diode. A small, solid state device used to indicate dimmer or control status; also used in signs and control units. Consumes low wattage and has a rated life of greater than 80 years.
Lens: Transparent or translucent medium that alters the directional characteristics of light passing through it. Usually made of glass or acrylic.
Lighting Controls: Devices which give you flexibility, decorative effects and multiple uses from your lighting sources. Today’s sophisticated dimming systems enable you to lower the light level to conserve energy and increase bulb life; vary the mood of a room; alter light source intensity; create lighting scene in each room. Types of controls include integrated dimming systems, touch dimmers, slide dimmers and rotary dimmers.
Light Distribution: Pattern of light produced by a fixture, or created in a room.
Light Sources: The performance of any light fixture depends on the light source, or bulb, that’s used. Different sources produce different effects.
Line Voltage Systems: 120 volt distribution is used mostly for lighting mounted to the outside of a house or for post-top lanterns along a drive or path. Line voltage landscape lighting can provide more light and handle greater distances than low voltage systems, but the installation is less flexible and more costly.
Louver: Grid type of optical assembly used to control light distribution from a fixture. Can range from small-cell plastic to the large-cell anodized aluminum louvers used in parabolic fluorescent fixtures.
Low-Pressure Sodium: A low-pressure discharge lamp in which light is produced by radiation from sodium vapor. Considered a monochromatic light source (most colors are rendered as gray).
Low Voltage Fixtures: Recessed track, task, decorative or landscape fixtures for low voltage lamps. A transformer is required for these fixtures and may by integrated, local or remote.
Low Voltage Housing: Recessed housing with an integral, or occasionally, remote transformer.
Low-Voltage Lamp: Incandescent lamps that operate at 6, 12 or 24 volts. Low voltage lamps require a step-down transformer to reduce the voltage from the normal household 120 volts. Popular lamps are MR11, MR16, and PAR36.
Low Voltage Lighting System: A type of lighting that operates on 12-volt current rather than the standard 120 volts. Power is supplied by a transformer, which is itself connected to 120-volt power.
Low-Voltage Switch: A relay (magnetically-operated switch) that allows local and remote control of lights, including centralized time clock or computer control.
Low Voltage Trim: Either a reflector trim with an integral transformer, which installs in a standard housing, or the dedicated trim to a low voltage housing.
Low Voltage Track: Track powered at low voltage by a step-down transformer, which installs in a standard housing; or the dedicated trim to low voltage housing.
Lumen: A unit of light flow, or luminous flux. The lumen rating of a lamp is a measure of the total light output of the lamp.
Luminaire: A complete lighting unit consisting of a lamp or lamps, along with the parts designed to distribute the light, hold the lamps, and connect the lamps to a power source. Also called a fixture.
Posted in Boston Magazine, Go Green, Lighting News, Lucia Press