Expressed in lumens, luminous flux indicates the total power of light emitted by a given source and able to produce a specific visual impression. The higher the luminous flux, the more light emitted by a given source. The luminous flux is determined by means of photometric measurement at a laboratory.
The colour temperature of a lamp (expressed in kelvins [K]) is the value equal to the temperature of an ideal black body that emits light of comparable colour to that of the lamp's light.
Warm colour (below 3300K) – the colour of the rising and setting sun. This is your typical “home” colour, the best for sitting back and relaxing.
Neutral colour (3300K–5300K) – resembles the light of the Moon. Our eyes perceive it as both pleasant and stimulating, as it gives off intense, clear light.
Cool colour (above 5300K) – the colour of the sky on a sunny, cloudless day. It makes you more active – the perfect colour to get things done.
An index with a value of 0–100, indicating the degree of how accurately the colours of objects’ colours are rendered in artificial light, as compared to model light. The value of Ra>80 is considered to be a very accurate rendition of colours.
The Power Factor is the correlation between active and apparent power. The higher its value, the lower are the power losses sustained by the device.
The lifetime of a lamp is the period of time, specified by the manufacturer and expressed in operating hours, during which the source of light is expected to remain fully operational. Statistically, however, over 80% of light sources continue to work fully after this period expires. For LED lamps, such operating periods can last up to 40,000 hours, i.e. more than a decade of service in daily home use.
When selecting a light fitting, make sure that its casing fits the spot in which it will be installed. The degree of protection is indicated by two digits:
the first digit – protection against foreign bodies (on a scale from 0 to 6, where 0 means no protection and 6 means full dust-tightness)
the second digit – protection against water (on a scale from 0 to 8, where 0 means no protection and 8 means complete water-resistance).
IP20 – protection against foreign bodies 12.5 mm in size and larger, and no protection against water.
and IP 40 – protection against foreign bodies 1 mm in size and larger, and no protection against water.
IP 44 – protection against foreign bodies 1 mm in size and larger, and protection against drops falling at any angle and from any side.
IP 65 – full protection against dust and water streams from any direction.
An indication showing how effective a device is in the use of electric energy. The classes are defined as E to A++, with A++ denoting devices which use energy the most efficiently and are therefore the most eco-friendly.