Master class on making a starting device for a car with your own hands. Consider portable starting devices for a car. Homemade starting device for a car 12 volt circuit.

The battery is a faithful friend and assistant in the most difficult situations, but, unfortunately, it does not last forever. It would be okay if the battery died instantly, without hope of recovery. But it gradually loses its characteristics, so it often turns out that it is simply impossible to turn the starter. The peak of battery failure occurs in winter, when it is especially difficult for equipment to start in cold weather. And then either a neighbor in the garage comes to the rescue with wires for lighting, or a spare battery. Or a good starting device, which every thrifty car enthusiast has.

Types of starting devices

Having some skills in radio electronics, we assemble a starting device for a car with our own hands. We will show drawings and photos, but first we will decide on its type, since they are different. Regardless of the type, it is important for us, as users, that the PU can work without the help of a battery and starts the engine not at the limit of its capabilities, turning red and smoking, but working stably even in severe frost. This is the most important condition when choosing a ready-made charging and starting device or assembling it yourself.

There is no special pickle here. The mechanism can be one of four types:

• pulse;
• transformer;
• battery;
• capacitor.

The essence of the work of each of them ultimately comes down to supplying the on-board electrical network with a current of the required rating and voltage, 12 or 24 volts, depending on the type of electrical equipment on board.

Transformer control panel, parameters

Transformer PUs are popular among DIYers. There is probably no need to explain the principle of their operation - it is a transformer that converts network electricity to the required parameters. These devices have one disadvantage - their enormous size and weight. But they are reliable and change the output parameters of voltage and current as needed. They are quite powerful and start the engine even with a dead battery. The simplest drawing for a transformer-based starter is shown below.

How to choose a transformer

To make the device yourself, it is enough to find a suitable transformer, and for a reliable start it must produce at least 100 A and a voltage of 12 V, if we are talking about a passenger car. If you ask a fifth grader, he will be able to calculate the power. In our case, it is 1.2, or better yet 1.4 kW. Without a battery, it will hardly be possible to start the engine with such current, because the starter needs at least 200 A. A standard battery will help spin the crankshaft, and while rotating, the starter consumes no more than 100 A, which is what our device will produce.

The core area cannot be less than 37 cm², and the primary winding wire must be at least 2 mm². The secondary is wound with copper wire with a cross-section of 10 squares, and the number of turns is selected experimentally so that the open circuit voltage is no more than 13.9V.

Diagram and details of PU assembly

Calculating the parameters of a transformer is not all. The device works like this. We connect the power wires directly to the battery terminals, while there is no voltage at the output of the control unit until the battery voltage drops below the response threshold of the thyristors, which are indicated in the diagram. As soon as the voltage at the battery terminals drops, the thyristors open the input and only then the electrical equipment is powered by the device. As soon as the voltage at the battery terminals rises to 12 V, the thyristors close and the device automatically turns off. This allows you to save the battery from overload.

The thyristor version can be assembled using two methods - using a full-wave circuit and using a bridge circuit. If the rectifier is a bridge rectifier, then the thyristors must be selected twice as powerful. That is, according to the first scheme, thyristors are designed for a minimum of 80 A, and with a bridge circuit - a minimum of 160 A. Diodes are designed for a current of at least 100 A. These elements are easily recognized by their braided output tip. The KT3107 transistor can be replaced with the 361st. There is only one requirement for resistance in the control circuit - their power must be at least one Watt.

The output wires, naturally, must correspond to the current and, as a rule, for this they take an analogue from a welding machine. Naturally, they are no thinner than the secondary wire. The wire that connects the network has a cross-section of each core of at least 2.5 square millimeters. A simple and reliable assembly that will start the engine in any frost. However, there are other options that you can buy in the store.

Pulse charger starting device

A pulse device is an excellent option when you need to constantly monitor the battery and keep it in working condition. Such designs operate on the principle of pulsed current conversion, and they are assembled on microprocessors and controllers. It cannot show much power, so it may not be suitable for starting, especially at severe subzero temperatures, but it is excellent for charging batteries.

They are compact, low in price, weigh very little and look nice. But the low power, or rather the low starting current that they produce, will not allow you to start the car with heavily discharged banks in the cold. In addition, precision electronics do not tolerate voltage surges and current frequency surges, which are not uncommon in our networks, and if something happens, not even every workshop can repair such a device.

Mobile control units

Another type of PU, or rather two at once, similar in principle of operation - battery and capacitor. A capacitor device works by discharging charged capacitors upon command. Their composition cannot be called particularly complex, but capacitors of such ratings themselves are quite expensive and cannot be restored after damage or drying out. They are used very rarely, although they are quite mobile, but due to high unregulated currents there is a risk of harming the battery.

Boosters, or battery starters, work even simpler. By and large, this is just an additional battery in a self-contained case. It was their autonomy that brought them popularity. They can be used even in the steppe, where there is no electricity. The pre-charged battery is connected to the on-board power supply and quietly starts the engine. In this case, it is important to choose the booster capacity and its starting current. It cannot be less than that of a standard battery. Household autonomous units have a capacity of 18 A/h, while more expensive and bulky, professional devices can have a capacity of about 200 A/h.

Any of these driver assistants will help start the engine, but there is nothing more reliable and cheaper than a transformer PU assembled by yourself. Good luck to everyone and have a quick start!

Charging and starting device presented in this article allows you to start the car in winter. As you know, starting the internal combustion engine of a car with a dead battery in winter requires a lot of effort and time.

The density of the electrolyte, due to long-term storage, decreases significantly, and the sulfation process occurring inside the battery increases its internal resistance, thereby reducing the starting current of the battery. Plus, in winter, the viscosity of engine oil increases, which requires more starting power from the car battery.

As you know, there are several ways to make starting a car easier in winter:

• heat the oil in the car crankcase;
• start the car from another car with a reliable battery;
• push start;
• use a charging and starting device (ZPU).

The option of using a starting device is more convenient when storing the car in a garage or in a paid parking lot, where it is possible to connect the starting device to the electrical network. In addition, this charger-starter It will not only help you start a car with a dead battery, but also quickly restore and charge it.

Basically, in industrial designs of a charging and starting device, the battery is recharged from a medium-power power source with a rated current of up to 5A, which, as a rule, is not enough to directly draw current from the car starter. Despite the fact that the internal capacity of car battery ROMs is very large (for some models up to 240 A/h), after several refills they somehow “sit down”, and it is not possible to quickly restore their charge.

This charging and starting device differs from the industrial prototype in its insignificant weight and the ability to automatically maintain the working condition of the ROM battery, regardless of the period of storage or operation. Even if the ROM does not have an internal battery, it can still provide up to 100A inrush current for a short period of time. There is also a good one with adjustable charge current.

To restore the battery plates and reduce the temperature of the electrolyte during charging, the charger and starter has a regeneration mode. In this mode, charging current pulses and pauses alternate.

Schematic diagram

The starting charger circuit contains a triac voltage regulator (VS1), a power transformer (T1), a rectifier with powerful diodes (VD3, VD4) and a starter battery (GB1). The charging current is selected by the current regulator on the triac VS1, its current is regulated by the variable resistor R2 and depends on the battery capacity.

The input and output charging circuits have a filter that reduces the degree of radio interference during operation of the triac regulator. Triac VS1 provides regulation of the charging current when the network voltage varies from 180 to 220 V.

The triac wiring consists of R1-R2-C3 (RC circuit), VD2 and diode bridge VD1. The time constant of the RC circuit affects the moment of opening of the dinistor (counting from the beginning of the network half-cycle), which is included in the diagonal of the rectifier bridge through the limiting resistor R4. The rectifier bridge synchronizes the switching on of the triac in both half-cycles of the mains voltage. In the “Regeneration” mode, only one half-cycle of the mains voltage is applied, which helps clean the battery plates from existing crystallization. Capacitors C1 and C2 reduce the degree of interference from the triac in the network to acceptable levels.

Details

The charger and starting device uses power from the Rubin TV. It is also possible to use a TCA-270 type transformer. Before rewinding the secondary windings (the primary windings remain unchanged), the frames are separated from the iron, all former secondary windings (up to the screen foil) are removed, and the free space is wound with copper wire with a cross-section of 1.8...2.0 mm2 in one layer (up to filling) secondary windings. As a result of rewinding, the voltage of one winding should be approximately 15 ... 17 V.

To visually monitor the charging and starting current, an ammeter with a shunt resistor is introduced into the circuit of the charging and starting device. Network switch SA1 must be designed for a maximum current of 10 A. Network switch SA2 (type TZ or P1T) allows you to select the maximum voltage on the transformer in accordance with the network voltage. The internal battery of the 6ST45 or 6ST50 brand should be enough for 3-5 simultaneous starts. Resistors in the ZPU can be used like MLT or SP, capacitors C1, C2 - KBG-MP, C3 - MBGO, C4 - K50-12, K50-6. The D160 diodes (without radiators) can be replaced with others with a permissible current of more than 50 A, the triac is of the TC type. The connection of the charger to the car battery must be made using powerful “Crocodile” clamps (for operating current up to 200 A). It is important to use grounding in the device.

Settings

When setting up, the internal battery GB1 is connected to the device (observe the polarity!), and the regulation of the charging current by resistor R2 is tested. Then the charging current is checked in charge, start and regeneration modes. If the current is no more than 10...12A, then the control unit is in working condition. When connecting the charging and starting device to the car battery, the charge current should initially increase approximately 2-3 times, and after 10 - 30 minutes it should drop to its original value. After this, switch SA3 is clicked into the “Start” mode, and the car engine starts. In case of an unsuccessful attempt to start the engine, additional recharging is performed for 10 - 30 minutes, and the attempt is repeated.

The starting charger allows you to start your car engine in winter. Since starting an internal combustion engine with a dead battery requires a lot of effort and time. The density of the electrolyte noticeably decreases in winter, and the sulfation process occurring inside the battery increases its internal resistance and reduces the starting current of the battery. In addition, in winter, the viscosity of engine oil increases, so the battery requires more starting power. To make it easier to start the engine in winter, you can warm up the oil in the car’s crankcase, start the car from another battery, push start it, or use a car starting charger.

The starting charger for a car consists of a transformer and powerful rectifier diodes. For normal operation of the starting device, an output current of at least 90 amperes and a voltage of 14 volts are required, so the transformer must be powerful enough, at least 800 W.

To make a transformer, it is easiest to use a core from any LATR. The primary winding should be from 265 to 295 turns of wire with a diameter of at least 1.5 mm, preferably 2.0 mm. Winding must be done in three layers. There is good insulation between layers.

After winding the primary winding, we test it by connecting it to the network and measure the no-load current. It should be between 210 - 390 mA. If it is less, then rewind a few turns, and if it is more, then vice versa.

The secondary winding of the transformer consists of two windings and contains 15:18 turns of stranded wire with a cross-section of 6 mm. The windings are wound simultaneously. The voltage at the output of the windings should be about 13 volts.

Wires connecting the device to the battery must be multi-core, with a cross-section of at least 10 mm. The switch must withstand a current of at least 6 Amps.

The starting circuit of a car charger contains a triac voltage regulator, a power transformer, a rectifier with powerful diodes and a starter battery. The charging current is set by the current regulator on the triac and is regulated by variable resistance R2 and depends on the capacity of the battery. The input and output charging circuits contain filter capacitors, which reduce the degree of radio interference during operation of the triac regulator. The triac operates correctly at mains voltages from 180 to 230 V.

The rectifier bridge synchronizes the switching on of the triac in both half-cycles of the mains voltage. In the “Regeneration” mode, only the positive half-cycle of the mains voltage is used, which cleans the battery plates from existing crystallization.

The power transformer was borrowed from the Rubin TV. You can also take the TCA-270 transformer. We leave the primary windings unchanged, but we will redo the secondary windings. To do this, we separate the frames from the core, unwind the secondary windings to the foil of the screens, and in their place wind them with copper wire with a cross-section of 2.0 mm in one layer until the secondary windings are filled. As a result of rewinding, approximately 15 ... 17 V should come out

When adjusting, an internal battery is connected to the starting charger, and the charging current adjustment is tested with resistance R2. Then we check the charging current in charge, start and regeneration modes. If it is no more than 10...12 amperes, then the device is in working condition. When the device is connected to a car battery, the charging current initially increases by about 2-3 times, and after 10 - 30 minutes it decreases. After this, switch SA3 is switched to the “Start” mode, and the car engine starts. If the attempt is unsuccessful, we additionally recharge for 10 - 30 minutes and try again.

The diagram contains: stabilized power supply(diodes VD1-VD4, VD9, VD10, capacitors C1, SZ, resistor R7 and transistor VT2)

synchronization node(transistor VT1, resistors R1/R3/R6, capacitor C4 and elements D1.3 and D1.4, made on the K561TL1 microcircuit);

pulse generator(elements D1.1, D1.2, resistors R2, R4, R5 and capacitor C2);

pulse counter(chip D2K561IE16);

amplifier(transistor VT3, resistors R8 and R9);

power unit(optocoupler thyristor modules VS1 MTO-80, VS2, power diodes V-50 VD5-VD8, shunt R10, instruments - ammeter and voltmeter);

short circuit detection unit(transistor VT4, resistors R11-R14).

The scheme works as follows. When voltage is applied at the output of the bridge (diodes VD1-VD4), a half-wave voltage appears (graph 1 in Fig. 2), which, after passing through the circuit VT1-D1.3.-D1.4, is converted into pulses of positive polarity (graph 2 in Fig. 2). These pulses for counter D2 are a reset signal to the zero state. After the reset pulse disappears, the generator pulses (D1.1, D1.2) are summed up in counter D2 and when the number 64 is reached, a pulse appears at the counter output (pin 6) with a duration of at least 10 generator pulse periods (graph 3, Fig. 2). This pulse opens the thyristor VS1 and voltage appears at the output of the ROM (graph 4 in Fig. 2). To illustrate the limits of voltage regulation, graph 5 of Fig. 2 shows the case of setting almost the full output voltage.

With the parameters of the frequency-setting circuit (resistors R2, R4, R5 and capacitor C2 in Fig. 1), the opening angle of the thyristor VS1 lies within 17 (f = 70 kHz) - 160 (f = 7 kHz) electrical degrees, which gives the lower limit of the output voltage about 0.1 times the input value. The frequency of the generator output signals is determined by the expression

f=450/(R 4 +R 5)С 2

where the dimension f is kHz; R - kOhm; C - nF. If necessary, the ROM can be used to regulate only the AC voltage. To do this, the bridge on diodes VD5-VD8 should be excluded from the circuit (Fig. 1), and the thyristors should be connected back-to-back (in Fig. 1 this is shown by the dashed line).

In this case, using the circuit (Fig. 1), you can regulate the output voltage from 20 to 200 V, but it should be remembered that the output voltage is far from sinusoidal, i.e. Only electric heating devices or incandescent lamps can serve as a consumer. In the latter case, you can sharply increase the service life of the lamps, since they can be turned on smoothly by changing the voltage from 20 to 200 V with resistor R5. Setting up the ROM comes down to adjusting the level of protection against short circuit currents. To do this, remove the jumpers between points A and B (Fig. 1) and temporarily apply +Up voltage to point B. By changing the position of the slider of resistor R14, we determine the voltage level (point C in Fig. 1) at which transistor VT4 opens. The protection response level in amperes can be determined by the formula I>k /R10, where k=Up/Ut.c., Up - supply voltage; Ut.s. - voltage at point C at which VT4 is triggered; R10 - shunt resistance.

In conclusion, we can recommend the procedure for putting the ROM into operation and inform about possible replacements of components, tolerances and manufacturing features: the D1 microcircuit can be replaced with the K561LA7 microcircuit; microcircuit D2 - microcircuit K561IE10, connecting both counters in series; all resistors in the MLT type circuit are 0.125 W, with the exception of resistor R8, which must be at least 1 W; tolerances on all resistors, with the exception of resistor R8, and on all capacitors +30%; the shunt (R10) can be made of nichrome with a total cross-section of at least 6 mm (total diameter about 3 mm, length 1.3-1.5 mm). Put the ROM into operation only in the following sequence: turn off the load, set resistor R5 to the required voltage, turn off the ROM, connect the load and, if necessary, increase the voltage with resistor R5 to the required value.

To solve the problem of starting the engine in winter, we will use an electric starter that will allow motorists to start a cold engine even with a partially charged battery and thereby extend its life.

Calculation. Carrying out an accurate calculation of the magnetic core of the transformer is impractical, since it is under load for a short time, especially since neither the grade nor the technology for rolling the electrical steel of the magnetic core is known. Find the required power of the transformer. The main criterion is the operating current of the electric starter Istart, which is in the range of 70 - 100 A. Electric starter power (W) Rap = 15 Istart. Determine the cross-section of the magnetic circuit (cm 2) S = 0.017 x Rap = 18...25.5 cm2. The electric starter circuit is very simple; you just need to correctly install the transformer windings. To do this, you can use toroidal iron from any LATRA or from an electric motor. For the electric starter, I used the transformer iron of an asynchronous electric motor, which I chose taking into account the cross section. The parameters S = aw must be no less than the calculated ones.

The stator of the electric motor has protruding grooves that were used for laying the windings. When calculating the cross section, do not take them into account. You need to remove them with a simple or special chisel, but you don’t have to remove them (I didn’t remove them). This only affects the consumption of the electrical wires of the primary and secondary windings and the mass of the electric starter. The outer diameter of the magnetic core is in the range of 18 - 28 cm. If the cross-section of the electric motor stator is larger than the calculated one, it will have to be divided into several parts. Using a metal hacksaw, we saw through the outer ties in the grooves and separate the torus of the required cross-section. Use a file to remove sharp corners and protrusions. We carry out insulating work on the finished magnetic circuit using varnished cloth or fabric-based insulating tape.

Now we proceed to the primary winding, the number of turns of which is determined by the formula: n1 = 45 U1/S, where U1 is the voltage of the primary winding, usually U1 = 220 V; S is the cross-sectional area of ​​the magnetic circuit.

For it we take copper wire PEV-2 with a diameter of 1.2 mm. We first calculate the total length of the primary winding L1. L1 = (2a + 2b) Ku, where Ku is the stacking coefficient, which is equal to 1.15 - 1.25; a and c are the geometric dimensions of the magnetic circuit (Fig. 2).

Then we wind the wire onto the shuttle and install the winding in bulk. Having connected the leads to the primary winding, we treat it with electrical varnish, dry it and carry out insulation work. Number of turns of the secondary winding n2 = n1 U2/U1, where n2 and n1 are the number of turns of the primary and secondary windings, respectively; U1 and U2 - voltage of the primary and secondary windings (U2 = 15 V).

The winding is made with insulated stranded wire with a cross-section of at least 5.5 mm2. The use of busbar trunking is preferable. Inside the wire we place turn to turn, and on the outside with a small gap - for uniform placement. Its length is determined taking into account the dimensions of the primary winding. We place the finished transformer between two square getinaks plates 1 cm thick and 2 cm wider than the diameter of the wound transformer, having previously drilled holes in the corners for fastening with coupling bolts. On the top plate we place the leads of the primary (insulated) and secondary windings, a diode bridge and a handle for transportation. We connect the outputs of the secondary winding to the diode bridge, and equip the outputs of the latter with M8 wing nuts and mark them “+”, “-”. The starting current of a passenger car is 120 - 140 A. But since the battery and electric starter operate in parallel mode, we take into account the maximum electric starter current of 100 A. Diodes VD1 - VD4 type B50 for a permissible current of 50 A. Although the engine starting time is short, it is advisable to place diodes on radiators. We install any switch S1 with a permissible current of 10 A. The connecting wires between the electric starter and the motor are multi-core, with a diameter of at least 5.5 mm in different colors, and we equip the ends of the output tips with alligator clips.

The diagram of the starting-charger clearly shows that the thyristors are controlled by current pulses of the circuit capacitance C4 - transistors VT5, VT6, VT7 - diodes VD4, VD5. The unlocking phase of the thyristors and the flow of current in the power circuit depend on the rate of increase in voltage across the capacitor C4, that is, on the current through the resistances of the current regulator R23-R25 and through the start bipolar transistor VT3. VT3 turns on in the “start” mode if the voltage on the battery drops below 11 V. The key transistor VT4 turns on the control circuit when properly connected to the battery and protects it when the current is exceeded and the windings overheat. For reliable operation of this circuit, the halves of the secondary winding are required to be as identical as possible; they are usually made by winding them into two wires or by dividing the ends of the “pigtail” in two. The current flowing in the winding is measured by the voltage difference on the loaded and free halves, since they are loaded in turn.

For motorists, a dead battery can be a real problem. You should also take into account that starting a car in winter is quite difficult. In this regard, there is often a need to use a starting charger. Today, many manufacturers are ready to offer this product. The characteristics of chargers vary quite a lot. However, you can make a model of this type absolutely independently. For this purpose, it is necessary to familiarize yourself with the design of the device, as well as find out its basic configurations.

Diagram of a conventional charger

Includes a threshold transformer and a series of resistors. The instrument coil is most often used at 20 V. It should also be noted that the models have a damper. It is designed for resonant vibrations. Expanders in chargers are most often installed of the dynamic type. A wide variety of transistor blocks are used. To connect the model to the battery, clamps are used, which can vary quite significantly in shape.

6V device

The circuit of the starting-charger of this type of transformer assumes the use of a threshold one. However, first of all, you should make a durable case for the model. Making it yourself is quite simple. For this purpose, it became important to select sheets with a thickness of about 2.3 mm. In this case, the foundation needs to be further strengthened. To do this, many experts recommend using a foundation to build. After this, the transformer is installed. The coil should be next to it. In this case, it is best to select a low-frequency damper.

The output voltage must be at a level of 5 V. It should also be noted that ROM expanders for a car of this type are only suitable for dynamic ones. Field capacitors are used. To install them, first of all, all contacts are cleaned. Direct soldering of the elements occurs using a blowtorch. At the end of the work, the appropriate clamps are selected for the battery.

How to make a 10V charger?

Making such a starter-charger with your own hands is quite simple. In this case, you must first deal with the body of the model. Some people make it from boards. However, in this situation, much depends on the dimensions of the transformer. If we consider threshold analogues, they weigh a lot. Thus, the base of the device must be strong.

It is also important to make the model transportable. To do this, you need to fix the handles at the top for carrying the device. In this case, it is better to install the transformer in the center of the base. After this, the damper is installed. If we consider linear resonant analogues, then they must withstand a minimum output voltage of 10 V. In this case, the vector frequency should fluctuate around 44 Hz.

Next, to assemble a device of this type, you need to take an expander. Many in this situation prefer capacitorless modifications. However, in this case the load on the transistors will be quite large. It is more advisable to select aluminum type clamps for an autonomous start-charger. They are practically not subject to corrosion.

12V models

You can assemble this type of starter-charger with your own hands using electrostatic capacitors. Nowadays they are quite easy to get. For this device, it is necessary to make a platform in the housing. Before installing the transformer, a sealant must be laid on it. Only after this will it be possible to work on the inductor.

It is most often selected with a primary winding. In this case, capacitors for the model are more suitable for the open type. They can withstand a maximum output voltage of 20 V. It should also be noted that expanders in this case must be installed last. Before doing this, it is important to secure the damper. In some situations, regulators are also used to control power.

In this case, you need a good power supply. It should also be noted that it can only be installed with a zener diode. In order to fix the clamps on the device, you can use a welding machine. At the end of the work, all that remains is to secure the device damper. It is usually installed near the transformer. As the instructions say, the starter-charger must be checked for grounding before starting.

Single-phase modifications

To make this type of starter-charger with your own hands, you will need an integrated transformer. Nowadays, these modifications are quite popular among motorcyclists. First of all, when assembling the device, it is recommended to prepare all the necessary tools in advance. In particular, for self-production, a high-quality one is selected along with a set of keys. For a 12-24V starter-charger, the housing is made of metal sheets with a thickness of at least 1.4 mm.

You can simply screw them together using screws. After this, it is important to lay a rubber seal on the bottom of the case. Next, it will be possible to directly install the transformer. To fix it, many experts recommend making a special insert. It is a U-shaped stop. To do this, you need to take boards about 3.5 cm wide. To fasten them correctly, you must first take measurements of the body. The next step is to install a damper on the 12-24V starter-charger.

In this case, it can be used of the resonant type. This component must withstand the output voltage at 20 V. It should also be noted that capacitors for the model are purchased only of the open type. They are able to maintain a minimum frequency of 45 Hz. At the end of the work, all that remains is to fix the power supply and solder the wires to fix it on the battery.

Two-phase devices

To assemble this type of starter-charger with your own hands, you will need to use a powerful transformer. In this case, the coil must withstand its maximum output voltage at a level of 20 V. A wide variety of dampers are suitable for the device. In this case, much depends on the type of capacitors. Some experts in this situation prefer open modifications. They can last quite a long time.

Resistors for the device are suitable only for integral ones. They are easy to find in stores, but they cost a lot. Next, to assemble the device, you will need to use a powerful expander. Dynamic type modifications are not suitable in this case. Induction models are considered more stable. In order to fix the clamps, it is necessary to use a cable with a diameter of about 0.4 mm.

Three-phase models

Circuits of this type involve the use of powerful transistor blocks. In order to install them, you must first prepare a site for them. In this case, the body can be built as an open type without a top. In this case, the car starter-charger can be transported on wheels. Transistors in this situation are selected as network type. The minimum output voltage they can withstand is about 15 V.

The frequency parameter of these elements on average does not exceed 40 Hz. The transformer for the model is selected as a standard threshold type. In this case, the coil must be designed for low frequencies. The damper for a car starter-charger of this type is selected to be resonant. It only needs to be installed on the seal. Some specialists additionally install indication systems for three-phase modifications. They are needed in order to look at the panel at the output voltage level.

Application of pulse transformer PP20

The device circuits include transformers of the PP20 series, as well as resonant-type dampers. Capacitors for this model are suitable only for the electrostatic type. It is necessary to begin assembling the device by welding the base. For this purpose, metal sheets are prepared with a thickness of about 2.2 mm. Coils with a primary winding are used quite often in this case.

In this case, a wide variety of display systems are suitable. In general, the above transformer can withstand an output voltage of 15 V. Only magnetic zener diodes are used. Aluminum clamps can be successfully used as clamps. Their conductivity is quite good, but they differ in shape. In this case, it is better to give preference to small-sized modifications.

Use of PP22 transformers

Transformers of the PP22 type are very common today. The coils in this case are used with copper winding. Their density is quite high, and they can last a long time. However, such devices still have disadvantages. First of all, it should be noted that models with the specified transformer suffer from increased output voltage. Thus, sudden surges in the network can lead to complete overheating of the capacitors.

Resistors also often fail. If the device has an indication system, the diodes will burn out due to overvoltage. It is necessary to install transformers on the model only with seals. At the same time, the toggle switch is suitable for the P2 series. In turn, indicators are often used in the IN3 class.

I present to your attention a powerfulstarter charger for charging car batteries voltage of 12 and 24 volts, as well as starting engines of cars and trucks with the corresponding voltages.

Its electrical circuit diagram:

The power source for the starter-charger is 220 volts of industrial frequency. The power consumed from the source can range from tens of watts in charging mode (when the batteries are almost charged and have a voltage of 13.8 - 14.4 volts or 27.6 - 28.8 volts for a pair connected in series) to several kilowatts in the starting mode of the car engine starter.

At the input of the device there is a two-pole circuit breaker with a current Inom = 25 A. The use of a two-pole circuit breaker is due to the reliability of disconnecting both the phase and the zero, since when connected through a standard Euro plug (with a grounding contact), there is no certainty that a single-pole circuit breaker will turn off the phase and thereby the entire device will be de-energized. This circuit breaker (in my version) is installed in a standard wall-mounted box. Frequently turning on the power with this switch does not make sense, and therefore did not install it on the front (front) panel.

Both in the “Start” mode and in the “Charge” mode, the power transformer is turned on by the same magnetic starter KM1, whose coil voltage is 220 volts and the current switched by the contacts is about 20-25 amperes.

The most important part of the starter-charger is the power transformer. I won’t give the circuit data of the power transformer, since I don’t think everyone will rush to copy one to one, I’ll just say what, in my opinion, you should pay attention to. As we have already noticed from the diagram, the transformer has a secondary winding with a branch from the middle. Here, during calculations, and then in practice, it is necessary to set the voltage at the output of the device (clamps on batteries - easier than crocodiles), taking into account the voltage drop across the diodes (in my version D161-250) within 13.8-14.4 volts for 12 volt mode and 27.6-28.8 for 24 volt mode, with a load current of up to 30 amperes. I used crocodiles from the weight of the welding machine, and accordingly painted the plus one red.

The 12/24 volt mode is installed by contactors KM2, KM3, the power contacts of which, rated for 80 amperes, are connected in parallel, giving a total of 240 amperes.

A shunt is installed in the circuit on the 12/24 volt side, and the contacts of the magnetic starter of the "" mode are installed in the ammeter circuit break.Charge" This ammeter must measure the charging current. The scale limit in my version is 0...30 A. The circuit closes in charging mode.

Separately, I would like to talk about the “Charge" As you have already noticed, there is no charge current control circuit here, but it can be said to be maximum. Error? I think no. Let's look at the electrical equipment of the average car. So, there the relay regulator regulates not the charge current, but... drives the generator into the parameters of the on-board network of the car, the same 13.8-14.4 volts, respectively, if you wind the transformer correctly, taking into account the voltage drop on the power diodes, then compare this circuit the car's generator, and as the battery charges, the current will only drop.

And, do not forget, in a diode bridge it is necessary to take into account that two diodes operate in series, that is, the voltage drop must be multiplied by two.

Among the shortcomings of this circuit, I can only highlight the dependence of the network voltage on the charging current. Since my version will be used at service stations, where the network voltage changes little and its main task is to start trucks with a voltage of 24 volts, I don’t see the need to complicate the design. But the solution to the problem can be to install an autotransformer through the free contacts of the magnetic starter KM4, parallel to KM1. Best regards, AZhila.