Voltage
The operating voltage of the lamp.
In different types of equipment, the voltage of on-board networks is also different. Therefore,
car lamps for passenger cars are designed for a voltage of 12 V, and
car lamps for trucks(and other similar equipment, such as buses) are designed for 24 V. However, there are more specific options:
—
12/24 V. Lamps with the possibility of using in both types of on-board networks — both cars and trucks. Such versatility is found mainly among LED models, as well as in some varieties of xenon (see "Type"): these types of lamps are equipped with control circuits in which automatic adjustment to the voltage of the on-board network can be provided.
— 85 V. Value found in models with a xenon principle of operation (see "Type"). In this case, it means the voltage supplied to the lamp from the ignition unit (see below); the ignition unit itself is connected to the on-board network and is usually designed for 12 V. Data on the operating voltage of the lamp itself may be needed if you need to separately select the ignition unit for it.
— 40 V. Another option for increased voltage in xenon lamps; the meaning is completely similar to the 85 V described above, but it is much less common.
Colour temperature
The colour temperature of the light emitted by the lamp. The overall colour of the glow depends on this indicator; and note that the higher the colour temperature, the more “cold” the light looks, the closer it is to blue and blue. Traditional incandescent bulbs produce warm light at 2500-3000K, 3000-3500K can be described as "slightly warmer than neutral", neutral white corresponds to temperatures of
3700-4500K, higher values correspond to cooler shades, and temperatures
over 5000K characteristic of lamps with a blue (blue) colour of the glow.
Note that in this case the colour temperature of the lamp itself (more precisely, its filament or LED element) is indicated, and not the actual shade of the glow that it will give out; for the difference between these indicators, see "Glow colour". Also note here that it is possible to evaluate the shade of light by colour temperature in headlight lamps (see "Intended use"), for which the white colour of the glow is claimed. At the same time, this indicator has a very practical meaning: the warm colour of the light is considered optimal in wet weather, the neutral one gives the highest visible brightness, all other things being equal, and the cold “long-range” one can be subjectively pleasant for some drivers, and can also be used as an element of external tuning.
Increased brightness
The level of increased brightness provided by the lamp. This indicator is used by some manufacturers for marketing purposes: it describes how brighter a given model is than some "standard lamps". At the same time, the standards for comparison may be different, and impressive figures (in some models reaching 140%, that is, almost 2.5 times) are not always reliable — that is, a high-brightness lamp will not necessarily be just that much brighter than the “normal” model of the same type and power.
