Description of kinds of halogen lamps
- Halogen lamps (GLN)
- Principle of action
- Key parameters
- Standard schemes of inclusion
- Service life of halogen lamps
- Operational features of halogen lamps
- The small overview of the most often applied halogen lamps
- Halogen lamps with the power supply of 220-230 V
- Low-voltage halogen lamps
- Transformers for low-voltage halogen lamps
- Section of the bringing wires for low-voltage halogen lamps
Hello, dear readers! Are again glad you to welcome in the heading of "The electrician for beginners". As you already understood from the previous publication, the cycle of articles devoted to answers to questions of readers will be continued. In the previous article it was told about the most widespread types of lamps and their main characteristics. Today at the request of readers it will be in more detail told about such type of lighting instruments as halogen lamps.
Halogen lamps (GLN)
GLN is frequent in use call just halogen lamps, and because of it is considered to be that this type of lamps some special and that in them some unusual way of receiving light is used. Actually these lamps represent only advanced model of the ordinary glow lamp, and light in them turns out due to heat of thin tungsten thread.
At the same time they have the feature: this type of lamps contains in gas-filler small additives of halogens (bromine, chlorine, iodine) or their combinations. By means of additives it is possible to eliminate almost completely in the certain temperature condition such process as darkening of the flask and the reduction of the luminous flux caused by it. That is why the flask size in GLN can be strongly reduced owing to what, on the one hand, it is possible to increase pressure in gas-filler, and on the other hand, to make possible use of expensive inert gases as gases-fillers.
Modern halogen lamps have several advantages:
- Bright light during all the service life.
- The reduced sizes.
- The almost doubled service life in comparison with simple glow lamps.
- It is more than light at the same power thanks to higher light return.
Such lamp quite adequately will shine at the same time.
Principle of action
The atoms of tungsten which are taking off from the heated spiral do not reach flask walls (at the expense of what blackening of the lamp decreases), and come back in the chemical way. This phenomenon received the name of the halogen cycle. The graphic representation of this process is given below.
At first sight halogen technology is so faultless that the lamp turns out almost eternal. To the great regret, it not so. Here the matter is that the tungsten atoms which evaporated from one site of the spiral return halogens to other sites. Sooner or later in the halogen lamp the same processes, as in the simple glow lamp begin, that is some site of the spiral becomes rather thin, its temperature considerably increases and evaporation in this place of the spiral increases even more. It inevitably leads to burn-out.
The efficiency of the halogen cycle is highest at the small volume of the flask of the lamp, and the fact that all modern halogen lamps have the small sizes is explained by it.
The rated voltage of halogen lamps is divided into two groups: low (6, 12 or 24 V) and high (from 110 to 240 V). According to this division, distinguish halogen lamps of low and high tension. The power range practically corresponds to range at normal glow lamps (from 1 to 5000-10 000 W).
Working temperature and amount of the generated heat which is the main product of thermal radiators are rather big therefore halogen lamps are very sensitive to hit of water and are fire-dangerous. Besides, directly heating up part of the lamp is usually located rather close to the place of connection of power voltage. It imposes special requirements of material of which make cartridges and lamps for such lamps.
It is possible to add also that characteristics of lamps do not depend on ambient temperature.
Standard schemes of inclusion
The scheme of inclusion of halogen lamps of mains voltage differs in nothing from normal glow lamps: twisted in the lamp – and forgot to the following time.
Lamps of low tension eat from special transformers, and because of high currents instead of laying of uniform low-voltage network usually use several groups of lamps with the separate transformers feeding them. Halogen lamps are not sensitive to the sort of the feeding current (variable or constant).
Rules of installation of the most widespread low-voltage lamps when using low-voltage halogen lamps
Service life of halogen lamps
Standard service life of network and many low-voltage halogen lamps it is considered to be the period equal to 2000 h. The same parameter at separate low-voltage models can reach 4000 h. Mechanical impacts on lamps in use and also frequent inclusions and switching off of you reduce their service life.
Color temperature of halogen lamps is higher, than at well familiar traditional glow lamps. It makes 3000-3200 K. The color rendering index of halogen lamps is maximum and equal to 100 Ra.
Operational features of halogen lamps
Operational features of halogen lamps, in addition to already listed, affect two more additional aspects:
- Lamps in unary quartz flasks do not allow touch barehanded (what it was already told in the previous publication, so far as concerned the lamps which are most often applied in use about). It is explained by ability of quartz to crystallize around the foreign debris brought at such contact.
- Many models of network and special halogen lamps do not allow any provision of burning and demand special placement in your lamp (that is the lamp can burn normally all the service life, for example, only in horizontal position).
The small overview of the most often applied halogen lamps
In this section excessive will describe separately all technical characteristics of separately taken lamp. Everything will be a little simpler. Photos of the most often used halogen lamps and information on the field of their application are included below. The overview is broken into two parts.
Halogen lamps with the power supply of 220-230 V
Halogen lamp with the threaded socle. Serves for replacement of the simple glow lamp in your lamps.
The linear halogen lamp is intended for searchlights and lamps of outside lighting.
Low-voltage halogen lamps
The reflector halogen lamp with the aluminum reflector is intended generally for installation in open lamps.
The halogen low-voltage capsular lamp is intended for decorative pointed lighting. For example, for creation on your ceiling of effect of the star sky.
Transformers for low-voltage halogen lamps
Traditional transformers are rather simple in the device and the design. They differ in nothing from the analogs accepted in radio-electronic practice. Transformers can be both Sh-shaped, and toroidal. Below images of these transformers are provided.
Because of big working currents of lamps the section of the wire of secondary winding reaches occasionally 4 mm2. Safety locks of different types also are usually provided in the body what usually you are informed by marking on the body on. But the essential lack of electromagnetic transformers is their big weight. For example, the 300 W transformer can weigh 10-12 kg. Agree if to install such transformer under ceiling space, at any time wait for the collapse of the site or all ceiling.
To solve this problem, in our century of high technologies electronic transformers which on more strict classification are electronic power supply units were developed and implemented in life. These devices contain the converter increasing the frequency of power voltage from 10000 to 30000 Hz at the expense of what the size of the transformer and was reduced. The image of the transformer of this look given below will help to be convinced of it.
The mass of electronic transformers is small, and their size with increase in power increases slightly. Also they generate much less heat and work silently. How to choose the transformer for lamps that it served faithfully not one year? The answer to this question is rather simple, it is the best of all to give the most simple and elementary example.
For example, you need to connect three lamps on 50 W. In the sum 150 W turn out and you need the 150 W transformer. Or one more example. If you have to connect four 35 W lamps everyone, here in the sum 140 W turn out. That is and in this case you also need the 150 W transformer.
When using this type of transformers the underload on power from 5 to 15 W is allowed. But upon purchase of the transformer it is always necessary to consider that under no circumstances you should not buy the device with intentionally the overestimated power. That is at the total power of lamps of 140 W the 200 W transformer will be out of place – it at best will serve half a year.
Connection of such transformer is carried out rather just according to the following scheme:
As you see, at this scheme there is the svetoregulyator. Many specialists do not recommend to install such electrotechnical equipment for low-voltage halogen lamps, motivating it with the fact that the svetoregulyator will quickly fail. This a little wrong opinion. First, on sale there are svetoregulyator intended especially for such lamps. Secondly, if you use the simple svetoregulyator, simply periodicly include lighting at full capacity, and believe, such svetoregulyator will serve long enough.
Section of the bringing wires for low-voltage halogen lamps
At operation of halogen lamps of low tension it must be kept in mind that through the body of heat and, respectively, through the wires bringing to it rather big currents proceed that causes big losses of tension in wires.
It is possible to avoid it, having increased the section of the bringing wires. And the wire, the bigger section is longer it has to have.Top