Fluorescent lamps are now widely used because they have a much lower power consumption than equally bright incandescent lamps. They are available in light colors sunlight, cool white and warm white.
Fluorescent lamps Design and function
Fluorescent lamps are one of the gas discharge lamp. It consists of a glass tube, which with mercury vapor and an inert gas such as argon or krypton filled. The inside of the glass tube coated with phosphor. This converts the light generated in the operation of the ultraviolet light in a longer wavelength, ie, into visible light.
The lamp has two electrodes made of tungsten. By a short voltage pulse, the gas is ionized and therefore electrically conductive. To generate this ignition voltage, a ballast is required. Conventional control gear (CCG) consist of a choke coil and a starter. The starter consists of a neon lamp and bimetal. Parallel to the starter, a capacitor is connected to the radio interference suppression.
The ballast is connected in series with the fluorescent lamp. Parallel to the lamp is the starter. When switching a small current from the ballast flows through the first electrode of the lamp by the starter to the second electrode of the lamp and from there to the N-conductor. It comes to glow in the neon lamp to the starter. This heats the bimetal and which close to the neon lamp is shorted and goes out. Now, a high current from the ballast flows through the electrode of the lamp by the starter to the N-conductor. Due to the high current builds in the choke coil of the ballast to a magnetic field. Simultaneously by the high power of the lamp electrodes are heated. Electrons out from it.
Since the shorted glow lamp is not lit in the starter to cool the bimetal again – they open up again and the circuit is interrupted. This interruption of current flow causes a collapse of the magnetic field in the ballast. The collapsing magnetic field generated by the self-inductance of the choke coil a voltage surge of nearly 1000 volts. This high voltage is applied to the electrodes of the lamp and accelerates the electrons in the lamp at high speeds – the gas electrically conductive and light the lamp.
This usually runs from ignition process several times until it comes to a stable ignition. Therefore, fluorescent lamps flicker when turning several times until they light up. Since the ballast is an inductive resistor in the ground, this also has a power consumption which is around 10 watts. We must therefore not only the power of the fluorescent lamp to see solely, but must also add to the ballast! Nevertheless, the power consumption is significantly lower than the same light bulb!
A disadvantage of an individually-operated fluorescent lamp, is that it flickers to the rhythm of the line frequency of 50 Hz. Therefore, fluorescent lamps lamps are often offered as a double with two tubes in so-called double switch. This, the second lamp has a capacitive ballast. This leads to a phase shift of 180 degrees between two lamps, which cancels the flicker.
Today, apart from the conventional control gear(CCG), there are also electronic control gear (ECG). It is much more expensive, but it has several advantages:
- Soft in the lighting
- Low power dissipation
- With high-frequency operation, no blinking lights
- There is no reactive power compensation required
Finally, note:
Never broke a fluorescent light! Glass tube containing a small amount of mercury which toxic! Therefore, this lamp in any case should not disposed in the trash, but should be brought to the collection!