Sources of electric lighting
Artificial electric lighting in premises has to provide normal hygienic visibility conditions, necessary comfort and the cosiness.
Apply the systems of the general and combined lighting to performance of these conditions. The general lighting serves for illumination of all room space. Combined - it is carried out by means of lamps of the general lighting which provide the necessary illumination in all room, and lamps of spot lighting create the increased illumination in the workplace.
The combined lighting is most economic, allows to create the best conditions for work and rest. For distribution of the luminous flux in the necessary direction and protection it from the blinding action electric lamps are installed in the armature. The lamp together with the armature is called the lamp. Types of lamps are chosen depending on character of the environment, height of suspension, lighting requirements and the interior of the room.
Depending on type of the light source distinguish lamps with glow lamps and with fluorescent lamps.
Glow lamps represent the light sources working by the principle of temperature radiation. Glow lamps are the most widespread light sources so far. As filament in modern lamps use the spiral from high-melting metal, most often from tungsten. Filament can be one-spiral or multispiral. Flasks of glow lamps are vacuumized or filled with neutral gas (nitrogen, argon, krypton). Temperature of the warmed thread reaches 2600-3000 C.
The range of glow lamps differs from the daylight range in dominance of yellow and red beams. The light efficiency of glow lamps determined as the relation of power of beams of the visible range to the power consumed from the network circuit is very small and does not exceed 3,5%.
The industry the different types of lamps differing in rated values of power and tension, the sizes, the form of flasks, material and the size of socles, etc. are issued.
In designation of glow lamps of the letter mean:
- In — vacuum;
- — gas-filled;
- B — coiled-coil;
- BQ — coiled-coil krypton;
- DB — diffusion (with the opaque reflective layer in the flask);
- MO — spot lighting, etc.
The digit following the letter means supply voltage, and the second — lamp power in watts. Reflector lamps are issued the concentrated light distribution (ZK), average (ZS), wide (ZSh), mirror of neodymium glass of the concentrated or wide light distribution (ZKN, ZShN). Reflector lamps are intended for lighting of high rooms and open spaces, decorative lighting. Neodymium lamps are used where the high quality of the color rendition is necessary.
Decorative special lamps (D) can radiate white (BL), yellow, green (3), red (To), opal (About) beams.
Glow lamps with the mirror reflector — thermoradiators, quartz halogen are issued (KG-220-1200; IKZK-220-500).
Cartridges for electric lamps of incandescence are subdivided into two main groups: threaded and bayonet. In household lighting fixtures threaded cartridges are applied, as a rule, and subdivided by the size of threaded sleeves. E14 — with the diameter of 14 mm (for minions), E27 — with the diameter of 27 mm, E40 — diameter is 40 mm (power of lamps more than 1,0 kW). Cartridges make of non-ferrous metals, steel, porcelain and plastic. In the execution form cartridges subdivide into cartridges for screwing on on the nipple, cartridges with the flange and cartridges for suspension.
If the boss has the current carrying screw sleeve, then the sleeve has to be connected to zero, but not to the phase conductor. The electrical safety when replacing the electrolamp is provided to these.
Fluorescent lamps are electric lamps in which the electric power turns in light, irrespective of the thermal condition of substance, at the expense of the luminescence.Top