To connect halogen lamps 12 volts use a 220 volt transformer, 12 volts is the optimal voltage for the operation of a large number of lamps, which include halogen, LED and some "housekeeper" lamps.

Today, most often, a system of halogen lamps connected via a 12-volt transformer is used to create bright and economical lighting. In addition to the fact that halogen lighting has a full and bright spectrum of light, it can be installed in close proximity to places of high humidity, as such lamps have an increased level of energy security.

Types and structure of 12V transformers

Modern industry produces two main types of transformers:

1. Electromagnetic, or, as they are also called, toroidal. This name arose because of their shape, that is, a ring (or toroid) on which a winding of a large number of turns of copper wire is installed. They have a significant margin of safety, and their price is quite low. The main disadvantage is their large size and weight (about 3-3.5 kg), which limits their use in suspended ceiling lighting systems, furniture and compact lamps. They are also characterized by a strong susceptibility to power surges and overheating.
2. Electronic, or impulse. Their clear advantage is their small size, light weight and the presence of a voltage stabilizer, which increases the service life of the devices connected to it. Most models of pulse transformers are protected against short circuit, soft start and no overheating. Due to their parameters, such devices are most often used for the installation of lighting systems in suspended and stretch ceilings and furniture.

The principle of operation of electronic transformers is to convert 220 volts to 12 through electronics and semiconductor elements.

One of the minor drawbacks of this type of transformers is that they are not allowed to be connected to the network unless a sufficient load is connected to them. This parameter is indicated on the body of the product and in most cases ranges from 40 watts.

How to choose a transformer for halogen lamps?

The choice of a transformer should begin with determining its type. To create a lighting system, it is recommended to use more modern electronic devices, as they are compact in size, more reliable and ideal for home use.

The next step is to choose the power of the transformer. In this case, the main thing is to correctly calculate the future load that will be created by electrical appliances connected to it. Too much power will be impractical, and too little power can lead to constant overheating and increase the chance of a short circuit.

To determine the optimal power of the transformer, sum the power of the lamps that will be connected to it. For example, you are planning to create a bathroom lighting system that should consist of four halogen lamps (35 watts each). The total power in this case will be 140 watts. It is not recommended to take a transformer with a power "close" to the required one, it is better to leave some margin in case you need to connect additional lighting or you need to install an additional lamp. In this case, we take a safety factor of 0.15, which means adding at least 15% to the power of the transformer. As a result, we get an indicator of 161 watts. Since the standard powers of manufactured devices are 50, 60, 70, 105, 150, 200, 250, 300 and 400 watts, the optimal value for us is 200 watts.

To check the overall reliability of the system, a load transformer NT-12 is often used, which makes it possible to determine the maximum load on the system at which the automatic protection from short circuit. But for small power devices (with properly selected transformer parameters), the threat of a short circuit is very small.

Connecting lamps to a transformer

To create a simple 12V lamp lighting system, you will need the following items:

1. Single key switch. To install the switch inside the bathroom, you should choose a device model with moisture protection not lower than IP X3, and preferably IP X4, where X is the degree of protection against dust (in this case, it can be any), and the number is the degree of protection against moisture. A rating of 3 means protection against splashes that fly at an angle of up to 60 °, 4 - resistance to all-round splashes and drops.
2. When the switch is moved outside the boundaries of a room with high humidity, the type of switch does not matter, but the wiring should be carried out in a hidden way in accordance with the requirements of the rules for the installation of electrical installations (PUE).
3. Junction box. It is used to simplify the subsequent repair or re-equipment of the lighting system. In the bathroom, it is best to use models with protection against dust and moisture not lower than IP55.
4. Pulse transformer 220 12 volts. As mentioned earlier, this device is used to convert the mains voltage from 220 to 12V.
5. Lighting system with halogen lamps. All lamps are connected to the transformer in parallel with the device terminals marked Output. The connection is made using separate copper wires, the cross section of which is at least 1.5 mm 2. To achieve a uniform glow of all lamps, you should choose wires with strictly the same cross section and length.

Electrical wires connected to the switch lead to junction box where they are connected to cables connected to the input terminals of the transformer. At the same time, it is important to observe the color coding of the cables, as this will facilitate future possible repairs or re-equipment of the lighting system. From the transformer, through the output terminals, the wires are connected in parallel to the halogen lamps, observing the same length and cross section of the individual wires.

There are other, more complex schemes for connecting the lighting system. For example, with a pair of lamps, they are divided into two groups, each of which is connected to a separate transformer. As a result, we get two relatively independent groups of fixtures. If the transformer in one part of the system fails, the second one continues to function fully. Another advantage of this connection method is that the cost of two separate low power transformers can be even lower than the price of one powerful device.

Similarly, having two transformers, it is easy to connect to a two-gang switch, which will allow you to control two independent halves of the lighting system.

Conclusion on the topic

The use of a 220 12 volt transformer makes it possible to create a reliable, safe and economical lighting system with halogen lamps in the bathroom, toilet, kitchen or hallway.

Such lighting has a high protection against short circuit and allows installation even in conditions of high humidity (in the bathroom or in the kitchen).

The ease of creating halogen lighting by connecting to a pulse transformer allows even beginners to implement it, the main thing is to adhere to safety precautions when working with electrical equipment and use waterproof system elements.

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Low-voltage light sources today have gained quite wide popularity. Recessed halogen lighting fixtures are often found in offices, residential buildings, high-rise apartments, shop window lighting and many other places where lighting is required.

The main advantage of such a lighting device is a long service life and safety when using the lamp, which is due to the low voltage level. But to connect halogen lamps to 12 volts, it is necessary to have the right transformer selected.

The low-voltage halogen lamp can only be operated from the AC mains through a special power adapter - a step-down transformer. To date, the most popular are electromagnetic and electronic transformers for halogen light sources.

The electromagnetic adaptive device is characterized by large dimensions and weight, which limits its scope. Such devices inefficient and highly sensitive to changes in mains voltage alternating current. In turn, electronic devices for 12 volt halogen lamps are safer and have many additional functions: they are equipped with a protection device against overheating, voltage fluctuations and have a soft start function for lamps, which greatly increases their service life.

In order to qualitatively control the operation of a halogen lighting device, it is imperative to use a transformer that lowers the output voltage to 12 volts. Thereby lamps are protected from overvoltage and power surges.

Such converters normalize incoming electricity and give the desired voltage level from 6 to 24 volts at the output depending on the halogen lamp used. To date, there are two main types of step-down transformers, depending on the design of the device:

• toroidal winding converters;
• electronic or pulse step-down transformers.

Standard winding transformers considered the most affordable and easiest to use, and also have good power performance. It is easy to connect a halogen light source to such a device.

The principle of operation of such a converter is based on the electromagnetic interconnection of the coils of the device. But due to the use of the latter, such a transformer has serious disadvantages - a lot of weight, reaching several kilograms and dimensions which take up a lot of space. It is for this reason that such devices did not receive a step-down voltage. wide application at home.

Plus, the electromagnetic converting The device gets very hot during operation. which can adversely affect halogen lamps. In addition, overheating of toroidal winding transformers can lead to power surges in the home, thereby adversely affecting other household devices.

On the other hand, low voltage pulse converters, which are also called electronic transformers, have received the widest possible range of applications both in everyday life and in production. Such popularity is primarily due to the small weight and dimensions of the device. In addition, such the device qualitatively lowers the voltage without getting hot during operation. The only disadvantages of such a transformer for 12 volt halogen lamps are the rather high cost of the device.

Recently, pulse step-down transformers have appeared on the electronics market, which, even at the production stage, are equipped with built-in short circuit and overvoltage protection, which significantly extends the service life of both the converter and light sources.

Such electronic converters are often used for mounting halogen light sources in the furniture industry or suspended ceilings. According to the principle of operation, such a transformer differs from a winding counterpart in that energy conversion is achieved through semiconductor devices and electronic parts.

Features of the choice of transformer

In the process of choosing a transformer for 12 volt halogen lamps, it is imperative to take into account certain factors. First of all, determine device type: electronic or electromagnetic adapter. Recently, preference has been given to electronic converters for halogen light sources, which, due to their low weight and dimensions, can be used in any field of electrical engineering.

The main parameter of a step-down transformer, regardless of the type of device, is device power. Due to the fact that in most cases a parallel connection of halogen lamps is used, the power indicators of the transformer should be equal to the total power of all lighting fixtures. For example, if two lamps of 40 W are connected, then the power of the converter is 80 W plus a margin of 10-15%.

Naturally, the purchase of a transformer with an excessive power reserve is impractical for the simple reason that the cost of the device increases significantly. In addition, such a discrepancy leads to a breakdown of the converter, and often halogen lamps. Each the adapter has a minimum load rating necessary for the stable operation of the device.

The output voltage of the transformer must match the rating of the halogen lamps. Standard light sources are available with nominal voltages of 6, 12 and 24 V. But 12 volt light sources are the most popular. If halogen lighting is mounted in rooms with high humidity, then you need to purchase a converter that has galvanic isolation.

To connect a large number of 12 volt lighting fixtures to the adapter, it is not always it is advisable to use one expensive device with high power ratings. It is often better to purchase several low-power devices with less power and use them to connect separate groups of halogen light sources.

This option is more practical, since in the event of a failure of one of several adapters, only one group of lamps will not light up, while all other lamps will continue to illuminate the apartment. Wherein replacing one low-power lamp fixture will be much cheaper than buying an expensive high-power step-down transformer, since its price is proportional to its power ratings.

Features of the installation of the transformer

To connect several 12 volt halogen light sources to one step-down transformer, several popular options are used:

• into the gap of a single-gang switch;
• by combining halogen lamps into separate groups.

AT standard scheme connections orange and blue wires are connected to the primary terminals L and N of the converter input. In turn, halogen lamps are connected to the secondary output terminals of the step-down transformer. In this case, the wiring must be carried out copper cables appropriate section, which will ensure minimal energy loss.

To achieve a uniform glow of halogen light sources, they are connected by identical conductors in a parallel circuit. Wherein the cross section of the wires must be at least 1.5 mm square. If it is necessary to connect a large number of groups, parallel-connected halogen lamps, and there are not enough terminals at the output of the buck converter, then additional terminals are sold in electrical spare parts stores, the main thing is that the power of the device is enough.

Also important is the length of the wiring, ideally it should be no more than 3 m. Such parameters are considered optimal to reduce energy losses and prevent heating of conductors. Very long wiring gets very hot, giving off some of the heat to halogen lamps, which for this reason can often fail or have a different degree of glow. In a situation where it is impossible for any reason to reduce the length of electrical wires, the cross section of the latter is increased.

Rules for connecting a voltage converter

The procedure for connecting halogen lamps to a step-down transformer implies compliance with certain lighting wiring rules.

1. With a parallel connection of halogen lamps, the same length and cross section of electrical conductors going directly to different light sources must be observed. Otherwise, 12 volt lamps will have a different degree of glow, and the lighting in the room will be uneven.
2. Due to the fact that the halogen lamp is very hot, the minimum distance of the light source from the step-down transformer must be more than 20 cm.
3. If an electronic voltage converter is used, then the maximum length of the wiring from the device to the lamps should not exceed 5 m. In this case, the longer the wiring, the larger its cross section should be. Otherwise, the wires will simply start to heat up, and this one is highly undesirable.
4. It is unacceptable to mount the transformer on flammable surfaces without using additional protection from non-combustible materials.

Only by adhering to the above simple rules, connecting 12 volt halogen lamps to a step-down transformer will be carried out in compliance with all safety requirements.

Low voltage halogen lamps or 220 volt lamp

Naturally, many reasonably argue that it is easier to use standard 220 volt incandescent bulbs. This is partly true, but despite the initial costs of installing a converter for connecting low-voltage lamps Such lighting has a number of advantages.

First of all, the operational life and reliability of a halogen lamp will more than cover the cost of installing a transformer. Plus, due to the fact that modern adapters are equipped with additional protection systems against voltage surges and short circuits, 12 volt light sources will work much longer than standard 220 volt incandescent lamps.

The use of power step-down (rarely step-up) transformers is widespread. They are a fairly simple and inexpensive solution for the transform function. electrical energy, namely voltage and current. For those who are not particularly familiar with electrical engineering, I will clarify - transformers are an electrical machine consisting of a magnetic circuit of a certain shape, which contains windings insulated wire(copper most often). Depending on the number of turns on the transformer and its cross section, the voltage and current that is converted depends.

The simplest version of the transformer contains two windings. The input winding is called primary and the output winding is called secondary. Initially, each transformer is calculated for its power, voltage, current, frequency. Most often, you can find a conventional step-down transformer, in which the input winding is designed for a voltage of 220 volts, and the secondary for the voltage used by a particular device (the most common are 3, 5, 9, 12, 24 volts). The voltage depends on the number of turns, and the current strength depends on the diameter of the winding wire.

The connection diagram of the transformer is quite simple. Power is supplied to the input AC voltage). If this is an ordinary step-down trans, designed for a standard mains voltage, then we connect 220 volts. Polarity doesn't matter here. Usually on the electrical device itself it is written where it has, what kind of winding, how many volts it is designed for. Input wires (or leads, terminals) are usually made well insulated, located separately from the output. In principle, it is easy to understand which pins correspond to the input.

If you got caught power transformer, which does not have a clear indication, an inscription where it has input terminals, leads, wires, and you know for sure that it is 220 volts, then you can simply call the primary winding with a tester, multimeter. So, first we visually determine which conclusions are most similar to the input. Next, we begin to measure the resistance of the windings. Since the primary winding is designed for a higher voltage (220 volts), it means that it will have the greatest resistance relative to all the others. For example, for most step-down transformers about the size of an adult's fist, the resistance of the input, primary winding will lie in the range of 10-1000 ohms. The larger the transformer, the lower the resistance on its input winding.

The secondary winding of a power step-down transformer in a simple version has two leads (wires, terminals). It is wound with a wire of a larger diameter, in comparison with primary winding. There will be a reduced alternating voltage at its outputs (when we supply power to the input). Most devices require a constant low-voltage voltage, and since an alternating voltage comes out of the secondary winding, in most cases it is connected to a diode, rectifier bridge, which converts the alternating voltage to direct voltage.

Some electrical devices require several different low-voltage voltages. In this case, power step-down transformers are installed, which have one input winding (primary), designed for 220 or 380 volts, and several output (secondary). Or maybe secondary winding with midpoint. That is, at the output winding electrical machine(trans) 3 wires come out (one wire is common for two identical windings, well, along the wire coming from the other ends of these windings). Such step-down transformers will have two identical low-voltage voltages relative to the common wire, and the total voltage will be equal to the sum of these two voltages.

In industry, voltages of 380 volts are also widely used. Consequently, those transformers that are used there can be designed for both 220 volt and 380 volt input alternating voltage. If there is an inscription on such trances (input and output voltage), then it’s good. If it is not clear what input voltage the transformer is designed for, then - if 220 volts are applied to the trans, designed for 380 volts, at the output we will only get a lower voltage than it should initially give out, if, on the contrary, the trans is designed for 220 volts, and we apply 380 volts to it, then it will quickly start to warm up and soon it will simply fail.

P.S. Transformers are designed to work with alternating current, from a constant they will simply warm up, without giving out any voltage at the output. It is also worth considering that in most cases (when the windings are not connected to each other, for example, two primary ones that are connected in series), the polarity of the connection to the transformer terminals does not matter. The main thing is that you be sure that the device itself is designed for the voltage that you are going to supply and receive to it. And don't forget, power matters! Choose just such a transformer that your device can provide without overload the right voltage and current.