LED Lighting Glossary

A

Accent Lighting: A type of lighting used to highlight specific features or areas, such as artwork or under cabinets.  

Alternating Current (AC): Describes an electrical current where the voltage consistently switches directions. LED landscape lighting usually uses low-voltage AC. 

Amber Light: A shade of light that falls between orange and yellow, with a peak wavelength of around 595 nm. It is usually used in outside environments to enhance visibility and doesn’t attract bugs. This lighting can also be used outdoors to help marine wildlife not get confused by artificial light. 

Ambient Lighting: The overhead or general lighting in a room.

Ambient Operating Temperature: The temperature surrounding the LED and how it affects its operation. LEDs usually have a range of ambient operating temperatures in which they can work.  

B

Ballast: Device used in fluorescent (low-intensity discharge) or HID (high-intensity discharge) lamps to regulate the electrical current going to the light, preventing it from getting too much power and burning out

Ballast Bypass: The process of disconnecting the ballast from a fixture, typically done when installing LEDs into an incandescent or fluorescent fixture. (Also known as Type B Ballast Compatibility)

Ballast Compatible: When an LED light can work with an existing ballast in a light fixture, so the ballast isn’t required to be removed (Also known as Type A Ballast Compatibility). 

Beam Angle: A measurement of the angle of the cone of light emitted from a bulb or fixture. The larger the beam angle, the wider the area the light covers.  

Bluetooth Mesh: A type of wireless network that allows multiple devices to use Bluetooth technology to communicate simultaneously and decentralized without a host or hub, so all devices can talk to each other directly. For more information, see Mesh Network below. 

C

Canopy Lighting: An outdoor lighting solution mounted on an overhang or canopy that provides general overhead lighting in areas where people walk or drive (parking garages or walkways), improving security, safety, and convenience. 

Chip-On-Board (COB) Technology: Technology where the LEDs are directly manufactured onto the printed circuit board with a phosphor gel coating, which converts the emitted light into the desired color or CCT. 

COB Strip Lights: A strip that features a continuous line of light without the hotspots or visible gaps you see on traditional LED strips. 

Color Rendering Index (CRI): A measurement of how well a light accurately depicts color as it would appear in natural sunlight. Anything below an 80 CRI is considered poor, an 80+ CRI is considered good, 90+ is high, 95+ is ultra-high, and a CRI of 100 indicates perfect color rendering. 

Constant Current: When changes in voltage are used to maintain the flow of the electric current for LEDs, typically used in integrated LED fixtures and retrofit kits. 

Constant Voltage: When the current can increase or decrease as needed to maintain the voltage of a power source, used for LEDs that require a specific voltage to operate. This specific voltage is typically used with flexible strip lights. 

Correlated Color Temperature (CCT): The color of white being displayed. A lower value will emit a warmer light (2700-3500K), but the higher the value, the more natural (4000-4500K) or cooler (>5000K) the white light will be. 

Cove Lighting: A type of indirect lighting that involves installing lights in a recess or nook to reflect light off the ceilings or walls to create a soft glow. 

D

Decorative Lighting: Lighting used to enhance the design of the space and usually includes fixtures like chandeliers or pendant lights.

Dimmer Switch: Used to adjust the brightness of the light depending on your mood. These work by regulating the amount of current flowing through the light. 

Diode: A semiconductor device that allows the flow of a current in only one direction. LEDs (Light Emitting Diodes) use this property to emit light when the proper amount of current flows through the device. 

Direct Current (DC): A type of electrical flow where the electricity moves in one direction, typically supplied by batteries or converted from AC by power supplies used in LED lighting. 

Driver: Synonym for power supply. Often used when referring to constant current power supplies that can directly drive LEDs without additional circuitry. 

E

Efficacy: The ratio of lumens to wattage. LEDs have a higher efficacy because they use fewer watts to emit the same lumens as other lighting solutions. 

Efficiency: It is a measure of how well a light source produces illumination compared to the energy it consumes. Efficient lighting minimizes energy use and prolongs the lights lifespan.

F

Field Selectable: When specific settings can be adjusted directly on the LED fixture during installation. 

Flicker: When the LED flashes or blinks quickly, which may or may not be visible to the naked eye. This could indicate various things, including low-quality LED drivers, an incompatible power supply or dimmer for an LED light, or the bulb being old and needing to be replaced. Flicker can be distracting or cause eye strain. 

Flood Beam: A beam that offers wide and even coverage to light up larger spaces rather than focusing on one spot (usually a beam angle of 45 degrees or greater).  

Fluorescent: A traditional type of light consisting of gas and mercury vapor. Certain states have begun banning these lights. 

Foot Candle: A unit of measurement for the intensity of light on a surface. One footcandle equals one lumen of light over one square foot.   

Frequency: The measurement of the number of cycles over a length of time. When talking about LED lights, frequency can refer to the speed at which an LED is turned on and off to control light output. Measured in Hertz. 

Full Cutoff: By design, this fixture style directs all light down, eliminates wasted uplight, and controls light pollution. This is most common in wall packs.  

G

Glare: Light pollution caused by the beam angle, placement, lumens, or other various factors of a fixture that can lead to eye strain or poor visibility. 

H

Halogen: A bulb that creates light by mixing halogen gases and tungsten vapor and releasing the mix into a tungsten filament.   

HID (High-Intensity Discharge): A traditional form of lighting that creates an arc to produce gases that illuminate light. 

High Bay: Light fixtures ideal for higher ceilings (usually at least 20 feet tall) in commercial spaces. 

High-Pressure Sodium: A type of HID bulb that utilizes mercury vapors and sodium to light an electric arc. 

Hubless: Smart controllers that operate without needing a Wi-Fi hub connection.  

I

Incandescent: A type of lighting where an electric current passes through and heats a thin filament wire until it glows and produces light. 

IP Rating (Ingress Protection Rating): This rating describes the fixture's environmental protection for both physical objects and water intrusion. 

K

Kelvin: A temperature scale like Fahrenheit or Celsius, and is used to describe the Correlated Color Temperature (CCT) of lights.  Zero Kelvin or absolute zero is the temperature at which all molecular activity ceases. 

L

LED (Light Emitting Diode): A more energy-efficient device that provides a better quality light output than traditional lighting. 

Light Distribution Pattern: Choosing the correct distribution pattern ensures an area gets the right amount of light while preventing wasted light. The higher a light fixture is placed, the wider and softer the light spreads at a lower intensity. Many municipalities have regulations and laws about light distribution patterns in parking lots and other outdoor areas to ensure sufficient light for visibility while minimizing light pollution. 

Lumens: The measurement of all visible light emitted from a source.  

Lux: The amount of lumens per square meter in a space/area. Typically used more in European countries. 

L70 Rating: The rated lifetime of an LED measuring the time it takes for the light to emit 70% of its initial light output. This is when the LED should be replaced. 

M

Max Run: The length of a strip light, after which a noticeable reduction in light output occurs due to voltage drop. Additional power must be provided to extend beyond the max run.

Mercury Vapor: A HID bulb that uses vaporized mercury to light an electrical arc and illuminate a blueish-green light. 

Mesh Network: Networks in which multiple devices can communicate simultaneously with a hub system. If one node fails, the other nodes can communicate through alternate paths, reducing the risk of network failure. Examples include Bluetooth,  Zigbee, Matter, Thread, and Google AI.  

Metal-Halide: Type of HID bulb that incorporates metal halides and vaporized mercury to light an electrical arc. It is a more energy-efficient solution than the other HID bulbs. 

O:

Operating Voltage: The input voltage of a power supply or light that is required for proper operation. 

P

Photocell: Detects the presence of light and automatically turns lights on or off based on the available natural light. 

Power Adapter: A device that typically converts a higher AC voltage into a lower DC voltage for LEDs or other electrical devices.  

Power Factor: A ratio from 0 (least efficient) to 1 (most efficient) that describes how effectively electrical power is used in a circuit. 

Power Supply: Used to convert power into the needed operating voltage for electrical equipment. Devices such as LEDs and specific electronics need a lower voltage to prevent damage. 

Pulse Width Modulation Dimmer (12/24/36/48 V): This device controls an LED's light output by rapidly turning it on and off at high frequencies.  The frequency of this switching is high enough that the eye can’t perceive the flicker.  

R

Retrofit: Upgrading traditional lighting technologies to a new efficient one, like LEDs, by swapping out specific components without changing the fixture completely. 

RGB: LEDs that have Red + Green + Blue color options.

RGBW: LEDs that have Red + Green + Blue + White color options.

RGB+CCT: LEDs that have Red + Green + Blue + Warm White + Cool White color options. 

RGB+ACCT: LEDs that have Red + Green + Blue + Amber + Warm White + Cool White color options. 

S

SMD (Surface Mount Device):  LED chip mounted onto printed circuit boards (PCBs), most commonly used in LED strip lights. 

Strip Light: Multiple SMD or COB LED chips mounted onto a flexible circuit board, usually with an adhesive back. These customizable fixtures work in various applications, such as under or above-cabinet lighting in kitchens, vehicles, and stairways.  

Surge Protection: Installed to protect LEDs from any damages that could occur because of power surges in voltage or current. 

T

Task Lighting: Providing additional lighting in a specific area when performing activities that require focus, such as cooking or working. 

Tunable White: A light fixture or strip light that can adjust the color temperatures from warm to cool white based on your lighting needs or time of day. 

Transformer: Changes high-voltage alternating current into low-voltage alternating current to power low-voltage LED lights, typically used in landscape lighting.

TRIAC Dimming: This dimmer adjusts the brightness emitted from a fixture by reducing the power draw of lights in a circuit by cutting off the incoming AC waveform's beginning (leading edge) or end (trailing edge). It ensures compatibility for both LEDs and traditional bulbs. 

V

Voltage (V): A measurement of the electrical potential energy available to create the flow of current that powers a light fixture. 

Voltage Drop: Describes the reduction in voltage along an LED strip light. Too much voltage drop will result in a noticeable reduction in light output at the far end of the LED strip. (see Max Run). 

W

Wattage: The measurement of how much electrical power a bulb consumes. LEDs operate using less Watts than traditional bulbs.