FAQ for LED lights

>FAQ for LED lights

FAQ for LED lights


The spread of light from a luminaire. For example: a fitting such as a low bay ,which is closer to the floor,will have a wider beam angle to illuminate a given floor area while a high bay fitting will have a narrower beam.

A measure of the degree of colour shift objects undergo when illuminated by the light source as compared with those same objects when illuminated by a reference source of comparable colour temperature. The reference source has a CRI of 100.

The description used to describe the effect of heating an object until it grows incandescently. The emitted radiation, and apparent colour, changes proportional to the temperature; easily envisioned radiation, and apparent colour, changes proportional to the temperature; easily envisioned ,when considering hot meal in a forge that glows red, then orange, and then white as the temperature increases.

VO-Burning stops within 10 seconds on vertical specimen; drips of particles allowed as long as they are not inflamed.
HB-Slow burning on a horizonal specimen’s burning rate <76mm /min thickness <3mm or burning stops before 100mm.
TP(b)-Slow burning rate <50mm / min for thickness <3mm.
TP(a)-Self extinguishes and flaming and afterglow should not exceed 5 seconds once source the source of flame is removed.

Luminous flux is the measure of the perceived power of light produced by the LED, adjusting to reflect the varying sensitivity of the human eye to different wavelengths of light.

A high power LED, sometimes referred to as a power LED, is one that is driven at current of 350mA or higher.

The intensity of light falling on a surface area. If the area is measured in square feet, the unit of illuminance is footcandles(fc). If measured in square metres, the unit of illuminance is Lux.

The light output of a light source divided by the total electrical power input to that source, expressed in lumens per watt(lm/w).

Classifies and rates the degree of protection provided against intrusion (body parts such as hands and fingers), dust, accident contact, and water by mechanical casing and electrical enclosures.

The light producing semiconductor device that may or may not be incorporated into an LED.

An electronic circuit that converts input power into a current source -a source in which current ramains constant despite fluctuations in voltage fluctuations ,overvoltages, and voltage spikes.

A key component to maximize the uniformity of light, to make the backlight slim and to reorient the line or dot light source such as LED to the plate light source.

The international (SI) unit of luminous flux or quantity of light and equals the amount of light that is spread over a square foot of surface by one candle power when all parts of the surface are exactly one foot from the light source.

The active power divided by the apparent power (i.e product of the rms input voltage and rms input current of a driver.)

The unit of electrical power as used by an electrical device during its operation. Many lamps come with rating in watts to indicate their power consumption.

The total lumens emitted of a light source, system, or solution.

A measure of how well a light source products visible light expressed as lumens /Watt.