0
- 0–10 V dimming
- An analog dimming method in which a low-voltage control signal between 0 and 10 volts sets the light output of the driver. It is one of the most common dimming interfaces for commercial LED luminaires.
7
- 7-pin receptacle
- A standard twist-lock socket on top of a roadway or area luminaire that accepts a photocontrol or another control device. Three pins carry power and switching and the others carry dimming and auxiliary signals; the INTELIGHT Edge device can plug into it.
A
- Autonomy (days of)
- The number of days a solar or hybrid system can keep running from its batteries alone, with little or no sun or wind. Systems are sized so that their autonomy covers the worst stretch of weather expected at the site.
B
- Beam angle
- The angle of the cone within which a luminaire's intensity is at least half of its peak. Narrow beams throw light far; wide beams spread it over a nearby area.
- BUG rating
- An IES rating that grades the Backlight, Uplight and Glare of an outdoor luminaire, each on a scale of 0 to 5. Lower numbers mean less light where it is not wanted.
C
- Candela
- The unit of luminous intensity: how much light a source sends in one particular direction. Photometric files and polar curves are expressed in candelas.
- Class, Division and Zone
- Two systems used to classify hazardous locations. The North American Class and Division system groups areas by type of hazard (Class I gases and vapours, Class II dusts, Class III fibres) and by how often it is present (Division 1 or 2), while the Zone system used by IEC, ATEX and also in North America uses Zones 0, 1 and 2 for gases and 20, 21 and 22 for dusts.
- Colour rendering index (CRI) and R9
- The colour rendering index (CRI, or Ra) scores from 0 to 100 how faithfully a light source shows colours compared with a reference source. R9 is a separate score for saturated red, which the general CRI leaves out and which matters for skin tones, food and signage.
- Correlated colour temperature (CCT)
- The colour appearance of white light, given in kelvin (K). Lower values such as 3000 K look warm; higher values such as 5000 K look cool.
D
- DALI
- Digital Addressable Lighting Interface, a two-wire digital protocol defined in IEC 62386. Each luminaire can be addressed, dimmed and queried individually.
- Depth of discharge
- The share of a battery's capacity that is used before it is recharged. Shallower discharges generally give a battery a longer cycle life.
- DMX
- DMX512, a digital control protocol that comes from entertainment lighting and is widely used for colour-changing architectural and façade lighting. Each fixture or colour channel has an address and is updated many times a second.
- Driver
- The electronic power supply that converts mains or battery power into the constant current an LED needs. It also handles dimming, and its quality affects flicker, power factor and lifetime.
E
- Edge computing
- Processing data on or near the device that collects it, rather than sending everything to a distant data centre. It shortens response times and reduces the amount of data that has to travel over the network.
- Edge device
- A device installed in the field that collects data, connects to sensors and other systems, and can process data locally before sending it on. The INTELIGHT Edge device is one multi-communication-protocol device, mounted on a fixture or fully autonomous.
- Efficacy
- How much light a luminaire produces for each watt it draws, in lumens per watt (lm/W). Higher efficacy means the same light for less energy.
- ESCO
- An energy services company that funds and delivers an efficiency project and is paid from the savings the project produces. An ESCO project can be cash-flow positive from day one, with no out-of-pocket capital for the customer.
- Explosion-proof
- Equipment whose enclosure is built to contain an explosion inside it and stop it from igniting the gas or dust around it. In IEC and ATEX terms the equivalent type of protection is called flameproof (Ex d).
F
- Footcandle
- The imperial unit of illuminance, equal to one lumen per square foot. One footcandle is about 10.76 lux.
- Full cutoff
- A luminaire that sends no light at or above the horizontal and only a small amount just below it. The term is older; the BUG rating now describes uplight and glare more precisely.
G
- Gateway
- A device that links field devices and sensors to a wider network or the cloud, translating between their communication protocols.
- Glare
- Brightness in the field of view that causes discomfort or makes it harder to see. It depends on how bright the luminaire is, where it sits and what is behind it.
- Grid-hybrid
- A solar or wind system that can also draw power from the electrical grid when its own generation and storage run low.
H
- Hazardous location
- An area where flammable gases, vapours, dusts or fibres may be present in amounts that could ignite. Equipment used there must be designed and marked for that classification.
- High bay
- A luminaire for high ceilings, roughly 6 metres (20 ft) and above, such as in warehouses, plants and arenas. Lower ceilings use low bay luminaires.
- Highmast
- A tall pole or tower, often 20 metres or more, carrying a ring of floodlights to light large areas such as ports, yards and highway interchanges.
I
- IES distribution types
- IES classes that describe the shape of the area a roadway or area luminaire lights on the ground. Types I and II suit narrow roads and paths, Types III and IV wider roads and areas lit from the edge, and Type V gives a symmetrical pattern around the pole.
- IES file
- A standard text file, in the IES LM-63 format, that records a luminaire's measured light distribution. Lighting design software uses it to calculate light levels on a site.
- IK rating
- A rating from IEC 62262 of an enclosure's resistance to mechanical impact, from IK00 to IK10. An IK10 enclosure withstands an impact of 20 joules.
- Illuminance
- The amount of light falling on a surface, measured in lux or footcandles. Lighting standards and recommended practices set illuminance targets for each kind of space.
- Infrared
- Light just beyond the red end of the visible spectrum, invisible to the eye. Red light therapy devices combine red and infrared wavelengths.
- IoT (Internet of Things)
- Physical devices such as sensors, meters and cameras that are connected to a network and share data. INTELIGHT is a converged platform that enables everything smart and IoT, and builds the infrastructure it runs on.
- IP rating
- The ingress protection rating from IEC 60529: the first digit (0 to 6) rates protection against solids and dust, the second (0 to 9) against water. IP66, for example, is dust-tight and protected against powerful water jets.
L
- L70
- The number of operating hours after which an LED source is expected to give 70 % of its initial light output. It is the most common way of stating the rated life of an LED luminaire.
- Lease
- An agreement to use equipment in return for regular payments, so the customer pays over time from operating budgets. At the end of the lease the customer can buy the equipment at fair market value, buy it for $10 under a $10 buyout lease, continue the lease or end it.
- LiFePO4
- Lithium iron phosphate, a lithium-ion battery chemistry widely used in solar lighting and storage. It is valued for its long cycle life, thermal stability and safety.
- Light loss factor
- A multiplier used in lighting design to account for the light a system loses over time through lumen depreciation, dirt on the luminaire and other causes. Designing with it makes sure light levels still meet the target later in the system's life.
- Light trespass
- Light that falls outside the area it is meant for, such as onto a neighbouring property or into windows. Good optics, shielding and aiming keep it to a minimum.
- LM-79
- The IES method for measuring the electrical and photometric performance of a complete LED luminaire: light output, efficacy, distribution and colour. An LM-79 report is the basis of a luminaire's published performance data.
- LM-80 and TM-21
- LM-80 is the IES method for measuring how the light output of LED packages declines over thousands of hours of testing. TM-21 is the IES method for projecting that test data forward to estimate lifetime figures such as L70.
- Lumen
- The unit of luminous flux: the total amount of visible light a source emits in all directions.
- Luminance
- The brightness of a surface as the eye sees it, measured in candelas per square metre (cd/m²). Roadway lighting design often works in luminance, because drivers see the road surface rather than the light falling on it.
- Lux
- The metric unit of illuminance, equal to one lumen per square metre. One lux is about a tenth of a footcandle.
M
- Maintained illuminance
- The average light level a design still delivers once light losses over time are taken into account. Standards set their targets as maintained values, not as the initial light level of a new installation.
- MPPT charge controller
- A solar charge controller that uses maximum power point tracking to keep a panel working at the voltage where it produces the most power. It harvests more energy than a simple controller, especially in cold or cloudy conditions.
O
- Off-grid
- A system that generates and stores all of its own power, with no connection to the electrical grid.
P
- Photocontrol
- A light sensor that switches a luminaire on at dusk and off at dawn. On roadway and area lights it usually plugs into the receptacle on top of the fixture.
- Photometric design
- Choosing the type, position, mounting height and aiming of luminaires, and calculating the resulting light levels, uniformity and glare before anything is installed. At CONXCORP, every fixture comes with the design to place it.
R
- Rebate
- Money returned by a utility or government program for installing qualifying energy-efficient equipment. Grants and subsidies work in a similar way, and eligibility rules vary by region and program.
- Red light therapy
- Panels and devices that emit red and infrared light from LEDs, in formats such as wall and stand panels, portable panels, belts and masks. They are usually described by their wavelengths, in nanometres, and their irradiance, in mW/cm².
- Retrofit kit
- A set of parts, such as an LED module and driver, that upgrades an existing luminaire to LED while keeping its housing, pole or mounting.
- Roadway luminaire
- A pole-mounted luminaire designed to light streets and highways, with optics that spread light along the road and limit glare and spill. Its distribution is usually described by an IES type.
S
- Sensor
- A device that measures something in its surroundings, such as motion, light, temperature, air quality, water flow or energy use, and turns it into data.
- Sky glow
- The brightening of the night sky over populated areas, caused by light sent or reflected upward and scattered in the atmosphere. It hides the stars and affects wildlife; luminaires with no uplight help limit it.
- Solar resource and peak sun hours
- The solar resource is how much solar energy reaches a site over a day or a year. It is often expressed as peak sun hours: the number of hours of sunlight at 1,000 W/m² that would deliver the same daily energy.
- Surge protection
- A device that protects a luminaire's driver and electronics from voltage spikes caused by lightning or switching on the grid. Its capacity is stated in kilovolts, for example 10 kV or 20 kV.
T
- Tunable white
- A luminaire whose colour temperature can be changed from warm to cool white after installation, either in the field or through a control system.
U
- UGR
- The Unified Glare Rating, a CIE method for estimating discomfort glare from indoor lighting, on a scale of roughly 10 to 30. Lower values mean less glare; offices commonly aim for 19 or less.
- Uniformity
- How evenly light is spread over an area, usually given as a ratio such as average to minimum or maximum to minimum. Good uniformity avoids dark patches between bright ones.
W
- Wall washer
- A luminaire that spreads light evenly across a wall or façade from close range. Exterior wall washers are often linear and may offer white or colour-changing light.