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Lighting Terminology​

Watt (W)

A unit of electrical power. Lamps are rated in watts to indicate their power consumption. Power consumed over time equals the electrical energy used.

Voltage (V)

A measurement of the electronmotive force in an electrical circuit or device expressed in volts(V).


A ratio of miniumum illuminance to maximum illuminance. It is largely determined by the luminaire light distribution and the spacing between them

Power Factor (PF)

A measure of the phase difference between voltage and current on alternating current circuits. Power factor can range from 0 to 1.0 with 1.0 being ideal.

Luminous Flux

The rate of flow of luminous energy emitted by a “self-generated light” object. It is measured in lumens (lm).

Luminous Intensity

Describes the power of the source to emitted light in a particular direction measured in candela (cd).

Lux (lx)

The international unit(S1) of illuminance. One lux is equal to one lumen per square meter.

Beam Angle

The beam angle is not, as some seem to think, the entire light output from the front, rather it is the point at which the light output Lumens drop below 50% of the total light output. LED beam angles typically vary between 10° – 120°. The beam angle is the area where the light is at its most intense.

ECOLED employs different solutions for achieving the different beam angles of its products using optics such as lenses or reflectors and the options available will be listed within the technical details that accompany each product.

CRI – Colour Rendering Index

CRI is a quantitative measurement of how accurate a light source can reveal an objects’ true colour.

The CRI scale is 1-100 with 100 being daylight at noon on a clear day. The lesser the number, the harder it becomes to distinguish between colours, especially the likes of navy blue and black. To get the CRI of a light source, it is tested against a coloured swatch and each colour is given an R value. Each colour is given a percentage for each R value and the average is taken to reveal the CRI

•R01 Light Greyish Red
•R02 Dark Greyish Yellow
•R03 Strong Yellowish Green
•R04 Moderate Yellowish Green
•R05 Light Blueish Green
•R06 Light Blue
•R07 Light Violet
•R08 Light Reddish Purple
•R09 Strong Red
•R10 Strong Yellow
•R11 Strong Green
•R12 Strong Blue
•R13 Light Yellowish Pink
•R14 Moderate Olive Green

CRI in the 60’s is satisfactory for cool white light in areas such as industrial storage but not suitable for residential.

CRI in the 80’s is good and most commonly used for residential and most hospitality applications.

CRI in the 90’s is excellent and typically used in high-end retail and medical applications.



IP in simple terms means Ingress Protection. The protection an item might or might not have from either solid objects such as dust, moisture, or both.

THE FIRST NUMBER characterizes the level of protection from Solid Objects to tiny dust particles. Numbers 0 to 6 are used – the lower number indicating lesser protection:

0 No particular protection
1 Protected against a large part of the body such as a hand or from solid objects greater than 50mm
2 Protected against fingers or other object not greater than 80mm in length and 12mm in diameter
3 Protection against entry from tools, wires etc. that have a thickness of 1.0mm
4 Protection from entry from solid objects with a diameter or thickness greater than 1.0mm
5 Protection against the amount of dust that might interfere with the operation of the equipment
6 Dust Tight

THE SECOND NUMBER characterises the level of protection of an item’s internals from various forms of moisture such as drips, sprays, steam or complete submersion. Numbers 0 to 8 are used again with the lower number indicating lesser protection:

0 No particular protection
1 Protection from dripping water
2 Protection from dripping water
3 Protection from sprayed water
4 Protection from splashing water
5 Protected against water jets
6 Protected against heavy seas
7 Protected from the effects of immersion*
8 Protected against submersion*

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