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Today we will look at 3 simple chargers schemes that can be used to charge a wide variety of batteries.
The first 2 schemes operate in linear mode, and the linear mode primarily means strong heating. But the charger thing is stationary, and not portable so that the efficiency is a decisive factor, so that the only minus of the shown schemes is that they need a large cooling radiator, and otherwise everything is fine. Such schemes have always been applied and will be applied, since they have undeniable advantages: simplicity, low cost, not "shy" to the network (as in the case of impulse schemes) and high repeatability.
Consider the first scheme:
This scheme consists of a pair of resistors (with the help of which the charge voltage or the output voltage of the circuit is as a whole) and the current sensor that sets the maximum output current of the circuit.
If you need a universal charger, the scheme will look like this:
The rotation of the rapid resistor can be set any voltage at the output from 3 to 30 V. in theory, it is possible to 37V, but in this case the input must be submitted to 40V, which the author (Aka Kasyan) does not recommend. The maximum output current depends on the resistance of the current sensor and cannot be higher than 1,5A. The output current of the scheme can be calculated according to the specified formula:
Where 1.25 is the voltage of the support source of the LM317 microcircuit, RS - the resistance of the current sensor. To obtain the maximum current of 1,5A, the resistance of this resistor should be 0.8 ohms, but in the circuit 0.2 Ohm.
The fact is that even without a resistor, the maximum current at the output of the chip will be limited to the specified value, the resistor is to a greater extent for insurance, and its resistance is reduced to minimize losses. The more resistance, the greater the voltage to fall on it, and this will lead to a strong heating of the resistor.
The chip is necessarily installed on a massive radiator, not a stabilized voltage is applied to the input to 30-35V, it is slightly smaller than the maximum allowable input voltage for the LM317 microcircuit. It must be remembered that the LM317 chip can dispel a maximum of 15-20W power, be sure to consider it. It is also necessary to take into account the fact that the maximum output voltage of the circuit will be 2-3 volts less input.
Charging occurs with stable voltage, and the current cannot be larger than the threshold. This scheme can be used even for charging lithium-ion batteries. With short closures at the outlet, nothing terrible will not happen, just goes the current limit and, if the cooling of the chip is good, and the difference in the input and output voltage is small, the scheme in this mode can work endlessly for a long time.
All collected on a small printed circuit board.
Its, as well as printed circuit boards for the 2nd follow-up schemes, together with the general archive of the project.
Second scheme It is a powerful stabilized power source with a maximum output current to 10a, was built on the basis of the first option.
It differs from the first scheme in that the additional power transistor direct conduction is added here.
The maximum output current of the circuit depends on the resistance of the current sensors and the reservoir current of the used transistor. In this case, the current is limited at 7a.
The output voltage of the circuit is adjusted in the range from 3 to 30V, which will make it possible to charge almost any batteries. Adjust the output voltage using the same rapid resistor.
This option is great for charging automotive batteries, the maximum charge current with the components specified on the circuit is 10a.
Now let's look at the principle of operation of the scheme. At low current values, the power transistor is closed. With an increase in the output current, the voltage drop on the specified resistor becomes sufficient and the transistor begins to open, and the entire current will flow across the transistor open.
Naturally, due to the linear mode of operation, the scheme will be heated, the power transistor and the current sensors will be very tough. The transistor with the LM317 microcircuit is screwed into a total massive aluminum radiator. Isolate substrates of the heat sink do not need, since they are common.
It is very desirable and even necessarily the use of an additional fan if the scheme is operated on high currents.
To charge the batteries, the rotation of the trimmed resistor you need to set the voltage of the charge and all. The maximum charge current is limited to 10-amps, as the battery charge will fall. The short circuit diagram is not afraid, the current will be limited to CW. As in the case of the first scheme, if there is good cooling, the device will be able to longer tolerate such a mode of operation.
Well, now several tests:
As we see stabilization it works, so everything is fine. And finally third scheme:
It represents the system of automatic shutdown of the battery with full charge, that is, this is not a completely charger. The initial scheme was subjected to some change, and the fee was refined during the test.
Consider the scheme.
As we see, it is simple, it contains only 1 transistor, an electromagnetic relay and a small one. The author on the board also has a diode bridge at the entrance and primitive reversing protection, these nodes are not drawn in the diagram.
A constant voltage from the charger or any other power source is supplied to the circuit input.
It is important to note that the charge current should not exceed the permissible current through the relay contacts and the fuse response current.
When power is applied to the circuit input, the battery is charging. The diagram has a voltage divider, which is monitored by the voltage directly on the battery.
As charged, the voltage on the battery will grow. As soon as it becomes equal to the voltage of the schema, which can be set by rotating the trimming resistor, the stabilion will work, feeding the signal to the low-power transistor base and it will work.
Since the electromagnetic relay coil is connected to the collector chain of the transistor, the latter will also work and the specified contacts will open, and the further power supply to the battery will stop, at the same time, and the second LED will work, notifying that the charging is completed.
This charger I did to charge the car batteries, the output voltage is 14.5 volts, the maximum charge current is 6 A. But they can also charge other batteries, such as lithium-ion, since the output voltage and output current can be adjusted widely. The main components of the charger were bought on Aliexpress website.
These are these components:
The electrolytic capacitor of 2200 μF is still required to 50 V, the transformer for the TC-180-2 charger (how to disperse the TC-180-2 transformer Look at B), wires, a power plug, fuses, a radiator for a diode bridge, crocodiles. The transformer can be used by another, with a power of at least 150 W (for charging current 6 A), the secondary winding must be calculated for the current 10 A and produce a voltage of 15-20 volts. The diode bridge can be dial from individual diodes designed for current of at least 10a, for example D242A.
The wires in the charger must be thick and short. The diode bridge must be fixed on a large radiator. You need to increase the DC-DC radiators of the converter, or use the fan to cool.
Assembling charger
Connect the cord with the network fork and the fuse to the primary winding of the TC-180-2 transformer, set the diode bridge to the radiator, connect the diode bridge and the secondary winding of the transformer. Sold down the capacitor to the positive and minus conclusions of the diode bridge.
Connect the transformer to the 220 volt network and make measurements of the voltage multimeter. I got the following results:
- AC voltage at the outlook outlook 14.3 volts (voltage in 228 volts).
- Permanent voltage after a diode bridge and a capacitor 18.4 Volt (without load).
Guided by a diagram, connect with a diode DC-DC bridge down converter and a voltammermeter.
Setting the output voltage and charging current
On the DC-DC tab of the converter, two trimmed resistors are installed, one allows you to set the maximum output voltage, the other you can set the maximum charging current.
Turn on the charger to the network (nothing is connected to the output wire), the indicator will show the voltage at the device output, and the current is zero. Set the voltage potentiometer at the output of 5 volts. Close the output wires, the current potentiometer, set the short circuit current 6 A. Then eliminate the short circuit, disconnecting the output wires and voltage potentiometer, set the output of 14.5 volts.
This charger is not afraid of a short circuit at the exit, but when stirring can fail. To protect against cakes, a powerful Schottky diode can be installed in the break of the plus wire of the battery. Such diodes have a small voltage drop with direct inclusion. With such protection, if you confuse polarity when connecting the battery, there will be no current. True, this diode will need to be installed on the radiator, since it will flow a long current through it when charging.
Suitable diode assemblies are used in computer power supplies. In such an assembly there are two Schottky diodes with a common cathode, they will need to be replenished. For our charger, diodes are suitable with a current of at least 15 A.
It should be borne in mind that in such assemblies the cathode is connected to the housing, so these diodes need to be installed on the radiator through an insulating gasket.
It is necessary to adjust the upper voltage limit once again, taking into account the voltage drop on protection diodes. For this, the voltage potentiometer on the DC-DC board of the converter must be set 14.5 volts measured by a multimeter directly on the output terminals of the charger.
How to charge battery
Wipe the battery with a rag moistened in soda solution, then dry. Remove the plugs and control the level of the electrolyte, if necessary, draw distilled water. Corks during charge must be twisted. Inside the battery should not fall garbage and dirt. The room in which the battery charges should be well ventilated.
Connect the battery to the charger and turn on the device to the network. During the charge, the voltage will gradually grow to 14.5 volts, the current will decrease with time. The battery can be conditionally charged when the charging current falls to 0.6 - 0.7 A.
The charger (memory) for the battery is necessary to each motorist, but it is worth it a lot, and regular preventive trips to the car service does not exit. Battery maintenance in a hundred requires time and money. In addition, on the discharged battery before the service still needs to be reached. Collect your own hands a workable charger for the car battery with their own hands will be able to everyone who knows how to use the soldering iron.
Little battery theory
Any battery (AKB) is an electrical energy drive. When the voltage is applied to it, the energy accumulates, thanks to chemical changes inside the battery. When the consumer is connected, the opposite process takes place: the reverse chemical change creates a voltage on the terminals of the device, the current flows through the load. Thus, to get a voltage from the battery, it first needs to be "put", i.e. to charge the battery.
Almost any car has its own generator, which, when the engine running, provides power supply to the on-board equipment and charges the battery, replete energy spent on the motor start. But in some cases (frequent or heavy launch of the engine, short trips, etc.) the battery energy does not have time to recover, the battery is gradually discharged. Exit from the created position one is charging an external charger.
How to find out the condition of the battery
To make a decision on the need for charging, you need to determine which state is the ACB. The easiest option is "twist / not twist" - at the same time is unsuccessful. If the battery "does not twist", for example, in the morning in the garage, then you will not go anywhere at all. The state "does not twist" is critical, and the consequences for the battery can be sad.
The optimal and reliable method of checking the state of the battery is the measurement of the voltage on it by the usual tester. At air temperature of about 20 degrees degree of charging degree On the terminals disconnected from the load (!) The battery is as follows:
- 12.6 ... 12.7 V - fully charged;
- 12.3 ... 12.4 in - 75%;
- 12.0 ... 12.1 B - 50%;
- 11.8 ... 11.9 in - 25%;
- 11.6 ... 11.7 V - discharged;
- below 11.6 V - deep discharge.
It should be noted that the voltage is 10.6 volts - critical. If it drops below, then the "car battery" (especially non-listening) fails.
Proper charging
There are two methods for charging the automotive battery - constant voltage and direct current. Everyone has their own features and disadvantages:
Homemade charging for batteries
Collect your own hand charger for the car battery is real and not particularly difficult. To do this, you need to have initial knowledge of electrical engineering and be able to keep a soldering iron in your hands.
Simple device on 6 and 12 V
Such a scheme is the most elementary and budget. With this memory, you can qualitatively charge any lead battery with an operating voltage of 12 or 6 V and an electrical capacity from 10 to 120 a / h.
The device consists of a lowering transformer T1 and a powerful rectifier collected on diodes VD2-VD5. The charging current is made by the S2-S5 switches, with which the C1-C4 capacitors are connected to the transformer power supply circuit. Due to the multiple "weight" of each switch, various combinations allow stepwise to adjust the charging current in the range of 1-15 A with increments of 1 A. This is sufficient to select the optimal charging current.
For example, if a current of 5 A is required, then you will need to enable S4 and S2 tumbler. The closed S5, S3 and S2 will be given in the amount of 11 A. to control the voltage on the battery serves the PU1 voltmeter, followed by the charging current using the PA1 ammeter.
In the design you can use any power transformer with a capacity of about 300 W, including homemade. It should produce voltage 22-24 at the secondary winding at a current to 10-15 A.. In place VD2-VD5, any rectifier diodes, withstanding direct current of at least 10 A and the reverse voltage not lower than 40 V. are suitable for D214 or D242. They should be installed through insulating gaskets on the radiator with an area of \u200b\u200bscattering at least 300 cm.
C2-C5 capacitors must necessarily be non-polar paper with an operating voltage not lower than 300 V. Suitable, for example, MBCH, KBG-MN, MBGO, IBD, IBM, IBGC. Such capacitors having the shape of cubes were widely used as phase shifting for electromotors of household appliances. As PU1, a DC voltmeter of the M5-2 type with a measurement limit of 30 V. PA1 is an ammeter of the same type with a measurement limit of 30 A.
The scheme is simple, if you collect it out of serviceable parts, it does not need it in establishing. This device is suitable for charging scest batteries, but the "weight" of each of the S2-S5 switches will be different. Therefore, to navigate in the charging currents will have to ammeter.
With smooth adjustment current
According to this scheme, collect the charger for the battery of the car with your own hands is more difficult, but it is possible in repetition and also does not contain scarce details. With it, it is permissible to charge 12-volt batteries with a capacity of up to 120 a / h, the charge current is smoothly adjustable.
Charging the battery is performed by a pulse current, a thyristor is used as an adjusting element. In addition to the smooth adjustment knob, this design has a mode switch, when the charging current is turned on twice.
Charging mode is monitored visually by the direction of RA1. R1 resistor homemade, made of nichrome or copper wire with a diameter of at least 0.8 mm. It serves as a current limiter. Lamp EL1 - indicator. In its place, any small-sized indicator lamp with a voltage of 24-36 V.
A lowering transformer can be applied with an output voltage along the secondary winding 18-24 at a current to 15 A. If the appropriate device did not turn out at hand, it can be done from any network transformer with a power of 250-300 W. To do this, with a transformer, all windings are clarified, except for the network, and wind one secondary winding with any insulated wire with a cross section of 6 mm. sq. The number of turns in the winding is 42.
Thyristor VD2 can be any of the KU202 series with letters in-N. It is installed on the radiator with an area of \u200b\u200bdissipation of at least 200 cm. Power installation of the device is made by wires of minimal length and with a cross section of at least 4 mm. sq. In place VD1, any rectifying diode with a reverse voltage is not lower than 20 V and withstand current of at least 200 mA.
The device is established to calibrate the ammeter RA1. You can do this by connecting several 12-volt lamps with a total capacity of up to 250 W, controlling the current according to a well-serviceable reference ammeter.
From a computer unit
To assemble this simple charger with your own hands, you will need a regular power supply from the old ATH computer and knowledge of radio engineering. But but the characteristics of the device will be decent. With it, they charge the battery to 10 A, adjusting the current and the charge voltage. The only condition - the BP is desirable on the TL494 controller.
For creating car charging with your own hands from the power supply of the computer We will have to collect the scheme shown in the figure.
Step-by-step necessary for the revision of the operation Will look like this:
- Bite all the wires of the power tires, with the exception of yellow and black.
- To combine the yellow and separate black wires among themselves - it will be, respectively, "+" and "-" memory (see scheme).
- Out all the tracks leading to the conclusions 1, 14, 15 and 16 of the TL494 controller.
- Install the variables of the resistors with a nominal value of 10 and 4.4 kΩ on the cover of BP - these are the voltage adjustment organs and charging current, respectively.
- Attachment to assemble the scheme shown in the figure above.
If the installation is performed correctly, then the improvement is completed. It remains to equip a new voice with a voltmeter, an ammeter and wires with "crocodiles" to connect to the battery.
In the design it is possible to use any variables and permanent resistors, in addition to the current (bottom according to the scheme with a face value of 0.1 Ohm). Its dissipated power is at least 10 W. You can make this resistor yourself from the nichrome or copper wire of the appropriate length, but really find and ready, for example, the shunt from the Chinese digital tester by 10 A or the C5-16MV resistor. Another option is two 5WR2J resistors turned on in parallel. Such resistors are in pulsed power supplies PC or TVs.
What you need to know when charging the battery
Chargeing a car battery, it is important to observe a number of rules. It will help you extend battery life and save your health:
The question of creating a simple charger for the battery with your own hands is clarified. Everything is quite simple, it remains to stock the necessary tool and you can safely begin to work.
The analysis of more than 11 schemes for making your own hands at home, new schemes 2017 and 2018, how to collect a fundamental scheme for an hour.
TEST:
To understand whether you have the necessary information about batteries and chargers for them, you should pass a small test:- What is the main reasons, the car battery is discharged on the road?
A) the motorist left the vehicle and forgot to turn off the headlights.
B) the battery is too heated under the influence of sunlight.
- Can the battery fail if the car does not use for a long time (it is in the garage without launch)?
A) with a duty, a simple battery will fail.
B) No, the battery will not deteriorate, it will only be necessary to charge and it will function again.
- Which current source is used to recharge the battery?
A) There is only one option - a network with a voltage of 220 volts.
B) network for 180 volts.
- Be sure to remove the battery when connecting a self-made device?
A) It is advisable to dismantle the battery from the installed place, otherwise the risk will damage the electronics by the intake of a large voltage.
B) it is not necessary to remove the battery from the installed place.
- If you confuse "minus" and "plus" when connecting the memory, then the battery will fail?
A) Yes, when improperly connected, the equipment is scorified.
B) Charger simply will not turn on, you will need to move the necessary contacts to the required places.
Answers:
- A) No headlights when stopped and minus temperature are the most common reasons for the battery discharge on the road.
- A) Akb fails if it is not necessary to recharge it for a simple car.
- A) to recharge the network voltage in 220 V.
- A) It is not desirable to charge the battery with a homemade device if it is not removed from the car.
- A) should not be confused by the terminals, otherwise the homemade apparatus is overrigent.
Battery On the vehicle require periodic charging. The reasons for the discharge can be different - starting from the headlights that the owner forgot to turn off, and to negative temperatures in the winter on the street. For feeding AKB It will take good charger. Such a device in large varieties is presented in auto parts stores. But if there is no possibility or the desire to buy, then Zause You can make it yourself at home. There is also a large number of schemes - they are preferably studied to choose the most suitable option.
Definition: The charger for the car is intended for the transmission of electric current with a given voltage directly to Akb.
Answers to 5 frequently asked questions
- Will it take some additional measures before you start charging the battery on your car? - Yes, you will need to clean the terminals, since acid deposits appear during operation. Contacts It must be cleaned very well to clean the current without difficulties to go to the battery. Sometimes motorists use lubrication to handle terminals, it should also be removed.
- What to wipe the terminals of the charger? - Specialized tool can be bought in the store or prepare yourself. As an independently made solution, water and soda use. Components are mixed and mixed. This is an excellent option for processing all surfaces. When the acid becomes contact with soda, then the reaction will occur and the motorist will definitely notice it. This place will need to thoroughly wipe to get rid of all acids. If the terminals were previously treated with lubricant, then it is removed by any clean cloth.
- If there are covers on the battery, then you need to open before you start charging? - If the lids are on the housing, they are definitely removed.
- For what reason do you need to unscrew the lids with the battery? - It is necessary that the gases formed in the process of charging are free from the housing.
- Is there a need to pay attention to the level of electrolyte in the battery? - This is done necessarily. If the level is lower than the required, then you need to add distilled water inside the battery. The level to determine will not be difficult - the plates must be completely covered with liquid.
Another important to know: 3 nuances of operation
Homemaking by method of operation is somewhat different from the factory option. This is explained by the fact that the purchase unit has built-in functions Helping in work. They are difficult to install on the device assembled at home, and therefore will have to adhere to several rules when operation.
- The charger assembled with your own hands will not be turned off when charging the battery. That is why it is necessary to periodically monitor the equipment and connect to it multimeter - To control the charge.
- Need to be very neat, not to confuse "plus" and "minus", otherwise charger grill.
- Equipment must be turned off when connecting to charger.
Fulfilling these simple rules, it turns out to correctly produce a feedback AKB And prevent unpleasant consequences.
Top 3 Charger Manufacturers
If there is no desire or the opportunity to collect with your own hands Pray That pay attention to the following manufacturers:
- Stack.
- Sonar.
- Hyundai.
How to avoid 2 errors when charging the battery
It is necessary to comply with the basic rules to properly focus battery. by car.
- Directly to the electrical stub rechargeable battery It is forbidden to connect. For this purpose, charging devices are intended.
- Even device It is made high quality and of good materials, you still need to periodically observe the process. charging So that trouble do not happen.
Performing simple rules will provide reliable operation of independently made equipment. It is much easier to monitor the unit than after spending on the components for repair.
The simplest charger for the battery
Scheme 100% of the working memory by 12 volts
Look at the picture on the scheme Zause On 12 V. The equipment is intended to charge automotive batteries with a voltage of 14.5 volts. The maximum current obtained by charge is 6 A. But the device is also suitable for other batteries - lithium-ionic, since the voltage and output current can be adjusted. All major components for assembling the device can be found on Aliexpress.com.
Required components:
- dC-DC lowering converter.
- Ammeter.
- Diode Bridge KSRS 5010.
- Hubs 2200 μF by 50 volts.
- transformer TC 180-2.
- Circuit breakers.
- Plug for connecting to the network.
- Crocodiles for connecting terminals.
- Radiator for a diode bridge.
Transformer Any one is used, at its own discretion, the main thing is that its power is not lower than 150 W (with a charging current of 6 A). It is necessary to install thick and short wires on the equipment. The diode bridge is fixed on a large radiator.
Look at the picture on the Charger Scheme Dawn 2.. It is composed of original Head. If you master this scheme, you will independently create a high-quality copy, not different from the original sample. Constructively, the device is a separate unit closed by the body to protect the electronics from moisture and exposure to bad weather conditions. On the base of the case, a transformer and thyristors on radiators must be connected. A fee will be required that will stabilize the charge charge and control thyristors and terminals.
1 scheme of smart memory
Look at the picture of the intelligence scheme charger. The device is necessary for connecting to lead-acid batteries having a capacity of 45 amps per hour or more. Connect such a type of device not only to batteries, which is used daily, but also to duty or in reserve. This is a rather budgetary version of the equipment. It does not provide indicator, And the microcontroller can be bought the cheapest.
If there is a necessary experience, the transformer is going to do it. No need to install also audio alert signals - if battery It will be connected incorrectly, the discharge light light will notify the error. It is necessary to put the pulse power supply unit by 12 volts - 10 amps.
1 scheme of industrial memory
Look at the industrial scheme charger From Bars 8a equipment. Transformers are used with one power winding by 16 volts, several VD-7 and VD-8 diodes are added. This is necessary in order to provide a bridge scheme of the rectifier from one winding.
1 inverter scheme
Look at the picture of the diagram of the inverter charger. This device before starting charging discharges a battery to 10.5 volts. The current is used with the value of C / 20: "C" denotes the capability of the installed battery. Thereafter process The voltage rises to 14.5 volts, with the help of a discharge-charging cycle. The ratio of charge and discharge is ten to one.
1 Electronics Electronics
1 scheme of a powerful memory
Look at the picture on a powerful charger for a car battery. The device is used for acid Akb, having a high container. The device easily charges a car battery having a capacity of 120 A. Output voltage The device is adjusted independently. It ranges from 0 to 24 volts. Scheme Noteworthy in that there are few components installed in it, but it does not require additional settings.
Many could see Soviet charger. It looks like a small box of metal, and may seem very unreliable. But it is not at all. The main difference between the Soviet sample from modern models is reliability. Equipment has a structural power. In the event that to the old device Connect an electronic controller, then charger It turns out to revive. But if there is no such thing at hand, but there is a desire to collect it, it is necessary to study the scheme.
To features Their equipment includes a powerful transformer and rectifier, with which it turns out to be quickly charged even highly discharged. battery. Many modern devices will not be able to repeat this effect.
Electron 3m
For an hour: 2 Charging schemes do it yourself
Simple schemes
1 simplest scheme for automatic memory for auto battery
How often can car owners can't get a four-wheeled pet due to the lack of charge in the battery? Of course, if this incident happened in the garage near the charging unit or nearby is a friend with a car, ready to help start the starter, no special problems are foreseen.
Where things are worse, if neither the first nor the second option you can realize, especially the motorists suffer from this, which are not able to acquire expensive charging factory production. But in this case, you can find a solution if you make a charger for a car battery with your own hands.
Advantages and disadvantages of the self-made device
The main advantage of the self-made charger is its low cost, even if you do not have all the necessary parts, the savings will be tangible. Also, a significant advantage is the possibility of using unnecessary devices and devices as a source of materials for homemade memory.
The disadvantages of self-made charging of batteries include imperfection in operation. Alas, but the model cannot independently turn off when the maximum charge is achieved, so you have to control this process or supplement the invention by homemade automation, which is under the power of experienced radio amateurs.
Device parameters
As you feel well known, the entire network in a car is powered by a low voltage of a 12V DC, but the level of charging the car battery must be in the range from 13 to 15V. The charge current at the output of the device should be about 10% of the power supply capacitance. If the current is less, the charge will still occur, but the procedure will last much longer. Therefore, the choice of elements for the charger should be repelled from the operating parameters of the specific model of the lead acb and the network to which it will connect.
What is needed for memory?
Constructive charger includes such items:
Fig. 2: Example Installation of the Adjustment Resistor If you are going to charge the battery, you can only use the first three items, it will be more convenient for permanent use, at least control devices. But, before collecting all this in a single design, you need to make sure that the parameters of the charger after the assembly will meet your needs. The first thing that should correspond is the charging device transformer.
If the transformer does not fit
Not always in the garage or at home you will meet just such a transformer that will eat from 220V and produce 13 - 15V terminals on the weekend. Most models used in everyday life really have a primary reel on 220V, but at the output can be any nominal. To fix it, you will need to make a new secondary.
First, recalculate the transformation coefficient by the formula: U 1 / U 2 \u003d N 1 / N 2,
N 1 and N 2 - the number of turns in the primary and secondary, respectively.
For example, an electrical machine is used as a 42V power supply, and you want to get 14V for charger. Consequently, you need at 480 turns in the primary, make 31 rounds on the secondary of the charger. This can be achieved as by reducing the number of turns, deleting too much and by winding a new one. But the first option is not always suitable, since the transformer winding section may not withstand the current strength with a smaller number of turns.
U 1 * i 1 \u003d u 2 * i 2,
Where U 1 and U 2 is the voltage on the primary and secondary winding, I 1 and I 2 - the current flowing into the primary and secondary.
As you can see, with a decrease in the number of turns and voltages on the secondary winding, the current strength in it will increase in proportion. As a rule, the reserve in the section is missing, so after determining the current force under it, a new conductor is selected from the table of the table:
Table: Selecting section, depending on the current current
| Copper conductor | Aluminum conductor | ||
| Section
lived. mm 2. |
Talk, A. | The cross section lived. mm 2. | Talk, A. |
| 0,5 | 11 | — | — |
| 0,75 | 15 | — | — |
| 1 | 17 | — | — |
| 1.5 | 19 | 2,5 | 22 |
| 2.5 | 27 | 4 | 28 |
| 4 | 38 | 6 | 36 |
| 6 | 46 | 10 | 50 |
| 10 | 70 | 16 | 60 |
| 16 | 80 | 25 | 85 |
If the current value of the current at the output of the charger exceeds the desired 10% of the battery capacity, the current-limiting resistor is necessarily turned on into the chain, the value of which is proportional to the excess current.
Procedure for assembling charger for a car battery
Depending on the components and battery parameters you have, the assembly of the memory will differ significantly. In this example, manufacturing technology includes such steps:
But you must be repelled from the parameters of your electric machine. Therefore, if necessary, remove unnecessary windings or draw their conclusions (if any), wrap the secondary (if the existing does not give the desired level of voltage in the memory).
Fig. 5: Remote windings 
and on the secondary conclusions 9 and 9 '.
Fig. 7: Connect the conclusions 9 - To the terminals 2 and 2 'solder the terminals of the network cord.
Fig. 8: Connect the power cord - Collect the diode assembly on the textolite plate, as shown in the diagram. Due to intense heat release due to large charged currents, semiconductor devices are installed on the radiator.
Fig. 9: Diode assembly - Connect the bridge to the 12V conclusions, in this example it is 10 and 10 'terminals. The main elements of the charger are collected.
Fig. 10: Connect the 10 conclusions to the diode bridge - Between the output of the diode bridge and the terminals of the battery, install an ammeter with the measurement limit to 15 A.
Fig. 11: Connect an ammeter - In the ammeter chain, connect the current-limiting unit of resistors or the switch with the resistance adjustment function, they will allow you to change the validity of the charger current. Fig. 13: Connect a voltmeter
To protect the charger, both from the network, and from the lead battery you need to install two fuses. In the example of the high side of the charger under consideration, a fuse is used for 0,5A, and in the charging circuit of the lead battery 10a.
If you have a charger current regulator, you should start charging with a minimum value on the ammeter and smoothly increase it to the desired value. When accumulated in a sufficient charge in a battery, the ammeter will show about 1A, after which you can safely disconnect the charger from the network and use the battery for the purpose.
Fig. 14: The dependence of the charges of charge 
