To control the operation of all appliances in the house, including light sources, special devices are needed. We propose to consider what an electronic transformer for 12V halogen lamps is, its principle of operation, characteristics and video, how to connect the device yourself.

What is a lamp transformer

To control the operation of halogen lamps, it is necessary to use a step-down transformer for 12 volts, they protect light sources from surges and power surges. This device normalizes the incoming electric current, mainly used for small light bulbs, 6, 12 and 24 V. Most popular brands: 55-TASCHIBRA, Comtech, Italmac, Relco, SET-110 LV for Krypton 2 Year E60 lamps.

Photo - Transformer diagram for halogen lamps

There are two types of step-down transformers:

1. Toroidal winding;
2. Electronic or impulse.

principled winding transformer the most accessible and easy to use, it has an easy connection and good performance power. Its principle of operation lies in the connection between the coils of the device. But they have quite serious drawbacks, this is a significant mass, weight can reach several kilograms and extensive dimensions. Because of this, their area of ​​use is very narrow, most often it is either non-residential premises or industrial buildings (warehouses, hangars, bases, etc.). In addition, the electromagnetic transformer gets very hot when it is on, which has a bad effect on halogen bulbs, and contributes to the appearance of power surges in the apartment, which can damage other electrical devices, including incandescent lamps, office equipment, etc.

Photo - Toroidal transformer

low voltage pulse transformer also called electronic. It has a slightly wider application area due to its small dimensions and low weight. It also transforms electricity well, does not heat up during operation. Its disadvantage can be considered a high cost (the price varies from 500 to several thousand rubles). There are models of such transformers that are immediately sold with built-in surge protection and short circuits, it helps to prolong the performance of devices. They are often used if you need to place halogen lamps in furniture or walls. The principle of operation of these models differs from toroidal devices, they transform energy due to special semiconductor-type devices and universal electronic parts.

Photo - Disassembled electronic transformer

Connecting halogen lamps through a transformer is not a mandatory measure, but a very desirable one that helps save the family budget, extend the life of the bulbs and control their operation.

Video: transformers for Osram halogen lamps

Calculation and selection of transformers

Before you start working with the device, you need to calculate the required power of the transformer. At the moment, in any electrical shop you can buy devices with different capacities, so it is very important to choose a transformer according to your parameters. You need to be as accurate as possible, because. buying a powerful device is not rational, and a device that is too weak may not be able to cope with the task.

We suggest considering how to choose the right transformer for halogen lamps:

Let's say that you have 7 point halogen bulbs installed in your bedroom, with a power of 30 W and a voltage of 12 volts. The sum of the power of all lighting fixtures will be 210 watts, for safety we add 10-15 percent of the error or power reserve to this value - we get 241 watts. It turns out that you need to buy a step-down transformer to protect halogen lamps with no less than 240 watts, 12v characteristics (such devices are from OSRAM, Feron, Philips). Under these characteristics, a round electromagnetic transformer with a power of 250 watts (250w), voltage 220/12 is suitable.

Photo - Transformer for halogen lamps

Always choose the nearest higher value, the safety of your family and the life of the lamps depend on it.

Transformer installation

To connect a step-down transformer for multiple halogen lamps, two methods can be used:

1. Through a one-button switch;
2. By creating separate groups of electric lamps.

In this case, you need blue wires and orange color(depending on the country of manufacture of the device, they may vary slightly in shades), you must connect to the primary terminals L and N of the transformer input or "Input". On the opposite side of the transformer, halogen lighting fixtures must be connected to the secondary terminals of the Output step-down device. This action should be carried out only with copper conductors of small cross section, which provide a minimum loss of energy.

Photo - Electronic transformer Feron

Top tip: in order for the light of halogen lamps to be the same, it is necessary to select conductors that are completely identical to each other and connect them only in parallel, the cross section should be no less than one and a half square millimeter. There are also cases when the transformer has an insufficient number of terminals, they are not enough to connect all the necessary lamps. To solve this problem, you need to buy special additional terminals, they are sold in any electrical store.

You also need to choose the correct length of wires, ideally it is within one and a half to three meters, this is the optimal distance for data transmission without interference and energy loss in the conductors. In addition, if you make the wire longer, it will start to heat up during operation, which is a bad factor for halogen bulbs, they will burn differently, the brightness will differ in the same lamps of the same group. In the event that there is no way to shorten the length of the wire, you need to increase its cross section. For example, from 3 meters to 4, it is necessary to use a wire with a cross section of up to 2.5 mm 2. The power connection diagram is as follows:

Photo - connecting the transformer to the switch

Consider another option for connecting halogen lamp transformers.

The Russian Electrician Forum considers this method to be more practical and easier to use.

It is necessary to divide all the lamps that are in the same room (or building, if necessary) into several groups. Let's say there are seven bulbs in total, you get two groups of 3 and 4 bulbs each. In this case, for each group you need to buy a transformer, as for different devices, separate machines.

Photo - connecting a transformer for halogen lamps

This is very convenient, because when any transformer fails, the remaining one will function unchanged. Based on the previous calculations, their total power is 210 W, it turns out that one group has 120 W (you should buy a device for 150w), and the second 90 (each bulb is 30 W). We select transformers that meet these requirements (do not forget to sum up the amount of spare power - 10-15%).

Once every six months, check the performance of the transformers. If necessary, carry out scheduled repairs in Moscow, St. Petersburg and other cities, there are special institutions that provide such services.

The content of the article:

Transformers for halogen lamps

The electrical equipment in our house, including lighting, is powered by electricity, with a voltage of 220V. But an ordinary incandescent light bulb with a tungsten filament is yesterday. The efficiency is low, the durability is low, and the frequency of 50 Hz creates an additional load on the eyesight. The way out is to use a transformer for halogen lamps and with its help use high-frequency halogen lamps powered by low voltage electricity.

The transformer for halogen lamps lowers the voltage from 220V to 12V. Halogen lamps shine precisely from electricity with a voltage of 12V.

Transformers are divided into two types:

• winding (induction);
• electronic.

Winding and electronic transformers

The first type of device - a winding transformer for halogen lamps - consists of two copper windings that interact through an electromagnetic field.

The electronic transformer for halogen lamps converts electricity using numerous special devices.

Today, an electronic transformer for halogen lamps over a winding induction one has its advantages:

• light and compact with small dimensions;
• well protected: has a high degree of protection against short circuits;
• almost silent: has a low noise level;
• stable in operation without load (idling);
• equipped with overload protection and has overheating protection;
• allows soft start;

These features provide durability, extend the life of both the transformer and halogen lamps.

Note: for an electronic transformer for halogen lamps, the efficiency is 95-99% versus 75-80% for a winding transformer.

Selection of transformers

The calculation and selection of step-down transformers is carried out according to two main criteria:

• By output voltage.
• By rated power.

The first parameter shows what voltage halogen lamps can be connected using a transformer. The second gives the total power of the connected lamps connected with it. The value of the main parameters is displayed on the cover of the transformer housing.

Note: halogen lamps are connected in parallel through a transformer. In this case, their power is summed up, and the voltage remains unchanged. Unlike a parallel connection, a series connection sums up the voltage.

If you need to connect a large number of halogen lamps, they should be divided into groups. For this, the following arguments can be given:

• Connection without division into groups requires a more powerful and, accordingly, larger transformer. Therefore, there may not be enough space for its installation.
• If one transformer fails, only part of the lighting will go out.
• More powerful transformers are much more expensive.
• The operation of halogen lamps without power loss requires the use of wires no longer than 3 m.

By dividing the lighting into groups, we provide this condition.

The scheme for connecting fixtures each through its own transformer - Photo 07

Tip: when working, a transformer for halogen lamps, especially induction, can become very hot during operation. This must be taken into account when choosing a place for its installation.

Transformer diagrams

This transformer is widely used in household lighting products, such as table lamps with halogen lighting.

The widely used transformer (Fig. 2) incorporates a "TRIGGER DIODE" bidirectional dinistor and works in the following way: diode bridge rectifies alternating voltage to a half-sine wave at twice the frequency. The bidirectional dinistor D6 starts the transformer converter and half-bridge generation, which allows you to bring the frequency of the electric current at the output to 30-50 kHz.

More advanced transformers with the IR2161 chip are now being used. The use of a microcircuit, having only 8 contacts, significantly increased the reliability of device transformers, primarily due to a decrease in the number of constituent components. It is also highly technologically advanced, namely:

• load protection against short circuit;
• current overload protection (both protections have automatic restart);
• intelligent half-bridge driver;
• swing of the operating frequency, which reduces electromagnetic interference;
• powerful start at 150 μA;
• the ability to use with phase dimmers;
• compensated output voltage shift, which extends the life of the lamps;
• "soft" start start, which allows you to exclude current overloads from lamps.

Transformers for halogen lamps and transformers for LEDs: are they interchangeable?

The transformer for halogen lamps has its "relative" - ​​a transformer for led lighting. But even with the same rated power and output voltage, these transformers are not interchangeable devices.

The fact is that in a halogen lamp, the light source is the incandescent filament. The glow of the LED has a completely different physics. Electricity passes through the P / N junction of the diode and gives off part of the energy in the form of a photon of light. This difference in the physical phenomenon of the glow of a halogen lamp and an LED places different requirements on transformers. Without going into a deep analysis of transformer waveforms in the framework of this article, we will make inputs:

1. 12V at the output of an electronic transformer is the average voltage. In reality, there are short-term jumps up to 40V. A halogen lamp "swallows" this jump without damage, but for an LED it can be fatal.
2. In addition to short-term power surges, electronic transformers for halogens are characterized by instability of the output voltage. It can be in the range of 11-16V and depends on the mains voltage at the input, connected power, ambient temperature.
3. The halogen lamp transformer produces an unrectified voltage. It contains both positive and negative impulses. For long-term operation of the LED, a rectified voltage is required, the pulse amplitude graph of which is close to a straight line.

Halogen lamps. Wiring diagram for halogen lamps

Using halogen lamps, you can create many options for designer lighting of multi-level ceilings. To increase electrical safety and to save electricity, lamps are used not for 220 V, but for undervoltage 6 - 24 V. However, low-voltage halogens have the disadvantage of strong heating.

With a decrease in voltage, the current consumption of these lamps increases, which leads them to strong heating. For fire safety purposes, halogen lamps are equipped with special fireproof fittings. Another disadvantage is the use of transformers to power low voltage lamps.

But good specifications(economy, brightness of the glow luminous flux) are more important than the listed shortcomings. Such a connection scheme for spotlights can be installed in a damp bathroom. There are several types of halogen lamps, depending on their professional or household purpose, these are;

— linear type halogen;

— consular design lamps;

— lamps with a reflector;

- lamps for domestic use.

Halogen lamps can be rated for 220V or rated for low voltage. Low voltage lamps require the installation of low voltage transformers. The wiring diagram for halogen lamps is very simple. Connection through a transformer is carried out on the 220 V side and on the low voltage side.

All connections are made in junction box to be able to quickly troubleshoot. As usual, when connecting switches, a phase is supplied from the junction box to the switch. The phase conductor from the switch is connected to the conductor going to the phase L terminal of the transformer.

Also, the neutral wire of the N terminal of the transformer is connected to zero in the junction box. The connection of wires in the junction box can be made by Wago terminal blocks, soldering or crimping - in a way convenient for you, but subject to the requirements for connecting wires. Halogen lamps are connected from the transformer through terminal blocks. The length of the conductor to one lamp should not exceed 2 meters.

This is necessary in order not to limit the current of the lamps by the resistance of the wire, and to prevent a decrease in brightness. halogen lamp. If it is necessary to install the luminaire for a longer length, it is necessary to increase the cross section of the wires accordingly. For easy access when troubleshooting, hatches are installed on the ceilings next to the transformer. The transformer is also not recommended to be placed near heating systems.

When choosing the power of the transformer, all the powers of the lamps are summed up, then they determine maximum power transformer with a margin of 15%. If the power of the transformer exceeds 200W, then two transformers with lower power must be purchased.

Breaking down the lighting into several groups with a reduced power of transformers allows you to reduce the current load on the conductors and reduce the temperature of the transformer, which increases its service life. In this case, if one transformer fails, the rest will function normally. To control the overload, a circuit breaker is installed in the halogen lamp connection circuit.

Before proceeding with the consideration of the connection diagram, let's figure out what a halogen lamp is or, as the people say, a "halogen lamp".

A halogen lamp is a vessel made of glass and filled with iodine or bromine vapor. Actually, here lies the meaning of the name of the light bulb - the listed fillers are halogen elements.

Why do we need these light bulbs, you ask. The main advantage of halogen lamps is increased light output (up to 2.5 times) and long service life. It can also be noted that there is a wide selection of halogen lamps on the market - different forms(from standard to sophisticated) and a wide range of colors.

Due to what these parameters are achieved, you will interrupt again. The whole difference lies in the material and filler of the flask. Simple bulbs are made from ordinary glass, and halogen bulbs are made from quartz, which allows them to cope with high temperatures, while having the same power.

There are two types of lamps on the market:

• rated for 220 volts;
• rated for 12 volts.

When connecting the latter to the network, it is necessary to additionally install a voltage transformer, which will reduce the voltage from the standard 220 volts to the required 12.

What is the difference between 12 volt and 220 volt bulbs? Their difference is in the distribution of light and the power of heating. For example, if the base is made of easily melting or flammable materials, then it is more advisable to use 12 volt halogens. The strength of their heating is significantly different from their predecessors due to the application of a special reflective coating that does not transmit infrared radiation and thereby improves heating. Typically, technical aluminum is used as a coating.

Reflector lamps are produced in the form of cones and have the properties of an axial light source. The rest of the bulbs have the properties of the luminous flux. Thus, 12 volt halogen lamps have a more crowded light and belong to the class spotlights. They are used in apartments and places where there is no need for a large amount of light or where it is necessary to direct the light to a certain place, to mark the transition. Also, as noted above, they are used where the bases are afraid of overheating.

Now consider the connection diagram of these light bulbs. In the example, we took two transformers and five halogen bulbs. As practice shows, it is more profitable to buy several transformers of lower performance than one, but powerful. If the transformer breaks down, some of the lamps may burn out, so it is better not to save on it. A good transformer, of course, costs more, but it works better and lasts longer, and light bulbs burn out less often - in the end it will pay for itself.

We note right away that the sizes, colors and intervals are specially taken to make it easier to understand for users who are not very versed in electrics.

In the diagram, the red line represents zero, and the blue line, respectively, phase.

Now some explanation. Two wires go into the junction box:

• phase - blue;
• zero is red.

Then the phase goes to the switch, and from there it returns again in the box. Then it goes to all transformers. The neutral wire through the junction box also goes to the transformers.

From the transformers, phase and zero go to the terminal blocks - bolted connectors. From the terminal blocks, the wires are connected to the light bulbs. Instead of terminal blocks, you can use twisting, but firstly, it is of poor quality, and secondly, the terminal blocks are not so expensive.

All connection work is within the power of any man. The main thing is to follow the rules for working with electricity and do not forget about safety.

Halogen lamps are increasingly used every day in the decoration of various shopping malls and shop windows. Bright colors, saturation in image transmission give them more and more popularity. Their service life is much longer than conventional lamps. At the same time, they can work for a long time without shutting down. Halogens use filaments, but the glow process, in comparison with incandescent lamps, differs due to filling the balloon with a special composition. Such light bulbs are used in various lamps, chandeliers, kitchen furniture and there are 220 and 12 volts. A power supply for halogens with a voltage of 12 volts is necessary, because when they are directly connected to electrical network a short circuit will occur.

Specifications

The voltage of halogens is not only 220 and 12 volts. On sale you can find bulbs for 24 and even 6 volts. Power can also be different - 5, 10, 20 watts. Halogen lamps from 220 V are connected directly to the network. Those that operate on 12 V need special devices that convert the current from the network to 12 volts - the so-called transformers or special power supplies.

Twelve volt halogens work very well. Earlier, in the 90s, a large 50 Hz transformer was used, which ensured the operation of only one halogen lamp. AT modern lighting pulse high-frequency converters are used. They are very small in size, but they can pull 2 ​​- 3 lamps at the same time.

On the modern market There are both expensive and cheap power supplies. As a percentage, about 5% of expensive ones are sold, and much more cheap ones. Although, in principle, high cost is not a guarantee of reliability. Cool converters, unfortunately, do not use high-quality parts, but only use ingenious circuit "bells and whistles" that contribute to normal operation power supply at least during the warranty period. As soon as it ends, the device burns out.

Classification

Transformers are electromagnetic and electronic (pulse). Electromagnetic are affordable, reliable, they can be made if desired with your own hands. They also have their drawbacks - decent weight, large overall dimensions, temperature increase during prolonged operation. And voltage drops significantly reduce the life of halogen lamps.

Electronic transformers weigh much less, they have a stable output voltage, they do not heat up much, they can have short-circuit protection and soft start, which increases the life of the lamp.

Transformers for halogen lamps

The analysis will be carried out using the example of a power supply unit from Feron German Technology. At the output, this transformer has neither more nor less - 5 amperes. For such a small box, the value is amazing. The case is made in a hermetic way, with the absence of any kind of ventilation. This is probably why some instances of such power supplies melt from high temperatures.

The converter circuit in the first variant is very simple. The set of all the details is so minimal that it is hardly possible to throw something out of it. When listed, we see:

• diode bridge;
• RC circuit with a dinistor to start the generator;
• a generator assembled on a half-bridge circuit;
• transformer lowering the input voltage;
• a low-resistance resistor that serves as a fuse.

With a large voltage drop, such a converter will “die” by 100%, taking the entire “blow” on itself. Everything is made from a fairly cheap set of parts. Only transformers have no complaints, because they are made to last.

The second option looks very weak and unfinished. Resistors R5 and R6 are inserted into the emitter circuits to limit the current. At the same time, the blocking of transistors in the event of a sharp increase in current is completely not thought out (it simply does not exist!). Doubt causes electrical circuit(shown in red on the diagram).

Feron German Technology produces halogen lamps up to 60 watts. The current of the power supply at the output is 5 amperes. That's a lot for a light bulb like this.

When removing the cover, pay special attention to the dimensions of the radiator. For a 5 amp output, they are very small.

Calculation of transformer power for lamps and connection diagram

Various transformers are sold today, so there are certain rules for selecting the required power. Do not take a transformer too powerful. It will run almost idle. Lack of power will lead to overheating and further failure of the device.

You can calculate the power of the transformer yourself. The problem is rather mathematical and within the power of every novice electrician. For example, you need to install 8 spot halogens with a voltage of 12 V and a power of 20 watts. The total power in this case will be 160 watts. We take with a margin of 10% approximately and acquire a power of 200 watts.

Scheme No. 1 looks something like this: there is a single-gang switch on line 220, while the orange and blue wires are connected to the transformer input (primary terminals).

On the 12 volt line, all lamps are connected to a transformer (to the secondary terminals). Connecting copper wires must have the same cross section, otherwise the brightness of the bulbs will be different.

Another condition: the wire connecting the transformer to the halogen lamps must be at least 1.5 meters long, preferably 3. If you make it too short, it will start to heat up and the brightness of the bulbs will decrease.

Scheme No. 2 - for connecting halogen lamps. Here you can do it differently. Break, for example, six lamps into two parts. For each, install a step-down transformer. The correctness of this choice is due to the fact that if one of the power supplies breaks down, the second part of the fixtures will still continue to work. The power of one group is 105 watts. With a small safety factor, we get that you need to purchase two 150-watt transformers.

Advice! Power each step-down transformer with your own wires and connect them in the junction box. Leave the connections free.

Do-it-yourself power supply alteration

For the operation of halogen lamps began to be used impulse sources current with high-frequency voltage conversion. At homemade and establishing quite often expensive transistors burn out. Since the supply voltage in the primary circuits reaches 300 volts, very high requirements are placed on insulation. All these difficulties can be completely circumvented by adapting a ready-made electronic transformer. It is used to power 12-volt halogen lights in the backlight (in stores), which are powered by a standard electrical outlet.

There is a certain opinion that getting a homemade switching power supply is a simple matter. You can only add a rectifier bridge, a smoothing capacitor and a voltage regulator. In fact, everything is much more complicated. If you connect an LED to the rectifier, then when you turn it on, you can fix only one ignition. If you turn off and turn on the converter in the network again, another flash will repeat. In order for a constant glow to appear, it is necessary to bring an additional load to the rectifier, which, taking away useful power, would turn it into heat.

One of the options for self-manufacturing of a switching power supply

The described power supply can be made from an electronic transformer with a power of 105 watts. In practice, this transformer resembles a compact switching voltage converter. For assembly, you will additionally need a matching transformer T1, a surge protector, a rectifier bridge VD1-VD4, an output inductor L2.

Diagram of a bipolar power supply

Such a device functions stably for a long time with a low-frequency amplifier with a power of 2x20 watts. At 220 V and a current of 0.1 A, the output voltage will be 25 V, with an increase in current to 2 amperes, the voltage drops to 20 volts, which is considered normal operation.

The current, bypassing the switch and fuses FU1 and FU2, follows the filter that protects the circuit from interference pulse converter. The middle of the capacitors C1 and C2 is connected to the shielding casing of the power supply. Then the current enters the input U1, from where the low voltage is supplied from the output terminals to the matching transformer T1. AC voltage with another ( secondary winding) rectifies the diode bridge and smoothes the L2C4C5 filter.

Self assembly

Transformer T1 is manufactured independently. The number of turns on the secondary winding affects the output voltage. The transformer itself is made on a K30x18x7 ring magnetic circuit made of M2000NM grade ferrite. The primary winding consists of a PEV-2 wire with a diameter of 0.8 mm, folded in half. The secondary winding consists of 22 turns of PEV-2 wire folded in half. When connecting the end of the first half-winding with the beginning of the second, we obtain the midpoint of the secondary winding. We also make the throttle ourselves. It is wound on the same ferrite ring, both windings contain 20 turns each.

Rectifier diodes are located on a radiator with an area of ​​at least 50 sq.cm. Please note that diodes whose anodes are connected to the negative output are insulated from the heat sink with mica spacers.

Smoothing capacitors C4 and C5 consist of three K50-46 connected in parallel with a capacity of 2200 microfarads each. This method is used to reduce the overall inductance of electrolytic capacitors.

It would be better to install a surge protector at the input of the power supply, but it is possible to work without it. For the mains filter choke, you can use DF 50 Hz.

All parts of the power supply are surface-mounted on a board made of insulating material. The resulting structure is placed in a shielding casing made of thin sheet brass or tin-plated sheet. Do not forget to drill holes in it for air ventilation.

A properly assembled power supply does not need to be adjusted and starts working immediately. But just in case, you can check its performance by connecting a resistor with a resistance of 240 ohms to the output, with a dissipation power of 3 watts.

Step-down transformers for halogen lamps generate a very large amount of heat during operation. Therefore, several requirements must be met:

1. It is forbidden to connect the power supply without load.
2. Place the unit on a non-combustible surface.
3. The distance from the block to the light bulb is at least 20 centimeters.
4. For better ventilation, install the transformer in a niche with a volume of at least 15 liters.

A power supply is required for 12 volt halogen lamps. It is a kind of transformer that lowers the input 220 V to the desired values.