Every motorist sooner or later has problems with the battery. I did not escape this fate either. After 10 minutes of unsuccessful attempts to start my car, I decided that I needed to purchase or make my own charger. In the evening, after checking out the garage and finding a suitable transformer there, I decided to do the charging myself.
There, among the unnecessary junk, I also found a voltage stabilizer from an old TV, which, in my opinion, would work wonderfully as a housing.
Having scoured the vast expanses of the Internet and really assessed my strengths, I probably chose the simplest scheme.
After printing out the diagram, I went to a neighbor who is interested in radio electronics. Within 15 minutes, he collected the necessary parts for me, cut off a piece of foil PCB and gave me a marker for drawing circuit boards. Having spent about an hour, I drew an acceptable board (the dimensions of the case allow for spacious installation). I won’t tell you how to etch the board, there is a lot of information about this. I took my creation to my neighbor, and he etched it for me. In principle, you could buy a circuit board and do everything on it, but as they say to a gift horse...
Having drilled all the necessary holes and displayed the pinout of the transistors on the monitor screen, I took up the soldering iron and after about an hour I had a finished board.
A diode bridge can be bought on the market, the main thing is that it is designed for a current of at least 10 amperes. I found D 242 diodes, their characteristics are quite suitable, and I soldered a diode bridge on a piece of PCB.
The thyristor must be installed on a radiator, since it gets noticeably hot during operation.
Separately, I must say about the ammeter. I had to buy it in a store, where the sales consultant also picked up the shunt. I decided to modify the circuit a little and add a switch so that I could measure the voltage on the battery. Here, too, a shunt was needed, but when measuring voltage, it is connected not in parallel, but in series. The calculation formula can be found on the Internet; I would add that the dissipation power of the shunt resistors is of great importance. According to my calculations, it should have been 2.25 watts, but my 4-watt shunt was heating up. The reason is unknown to me, I don’t have enough experience in such matters, but having decided that I mainly needed the readings of an ammeter, and not a voltmeter, I decided on it. Moreover, in voltmeter mode the shunt noticeably warmed up within 30-40 seconds. So, having collected everything I needed and checked everything on the stool, I took up the body. Having completely disassembled the stabilizer, I took out all its contents.
Having marked the front wall, I drilled holes for the variable resistor and switch, then using a small diameter drill around the circumference I drilled holes for the ammeter. Sharp edges were finished with a file.
After racking my brains a bit over the location of the transformer and radiator with thyristor, I settled on this option.
I bought a couple more crocodile clips and everything is ready to charge. The peculiarity of this circuit is that it only works under load, so after assembling the device and not finding voltage at the terminals with a voltmeter, do not rush to scold me. Just hang at least a car light bulb on the terminals, and you will be happy.
Take a transformer with a voltage on the secondary winding of 20-24 volts. Zener diode D 814. All other elements are indicated in the diagram.
Hello uv. reader of the blog “My Radio Amateur Laboratory”.
In today's article we will talk about a long-used, but very useful circuit of a thyristor phase-pulse power regulator, which we will use as a charger for lead-acid batteries.
Let's start with the fact that the charger on the KU202 has a number of advantages:
— Ability to withstand charging current up to 10 amperes
— The charge current is pulsed, which, according to many radio amateurs, helps extend the life of the battery
— The circuit is assembled from non-scarce, inexpensive parts, which makes it very affordable in the price range
- And the last plus is the ease of repetition, which will make it possible to repeat it, both for a beginner in radio engineering, and simply for a car owner who has no knowledge of radio engineering at all, who needs high-quality and simple charging.
Over time, I tried a modified scheme with automatic battery shutdown, I recommend reading it
At one time, I assembled this circuit on my knee in 40 minutes, along with wiring the board and preparing the circuit components. Well, enough stories, let's look at the diagram.
Scheme of a thyristor charger on KU202
List of components used in the circuit
C1 = 0.47-1 µF 63V
R1 = 6.8k - 0.25W
R2 = 300 - 0.25 W
R3 = 3.3k - 0.25W
R4 = 110 - 0.25 W
R5 = 15k - 0.25W
R6 = 50 - 0.25W
R7 = 150 - 2W
FU1 = 10A
VD1 = current 10A, it is advisable to take a bridge with a reserve. Well, at 15-25A and the reverse voltage is not lower than 50V
VD2 = any pulse diode, reverse voltage not lower than 50V
VS1 = KU202, T-160, T-250
VT1 = KT361A, KT3107, KT502
VT2 = KT315A, KT3102, KT503
As mentioned earlier, the circuit is a thyristor phase-pulse power regulator with an electronic charging current regulator.
The thyristor electrode is controlled by a circuit using transistors VT1 and VT2. The control current passes through VD2, which is necessary to protect the circuit from reverse surges in the thyristor current.
Resistor R5 determines the battery charging current, which should be 1/10 of the battery capacity. For example, a battery with a capacity of 55A must be charged with a current of 5.5A. Therefore, it is advisable to place an ammeter at the output in front of the charger terminals to monitor the charging current.
Regarding the power supply, for this circuit we select a transformer with an alternating voltage of 18-22V, preferably in terms of power without reserve, because we use a thyristor in the control. If the voltage is higher, raise R7 to 200 Ohm.
We also do not forget that the diode bridge and the control thyristor must be installed on the radiators through heat-conducting paste. Also, if you use simple diodes such as D242-D245, KD203, remember that they must be isolated from the radiator body.
We put a fuse at the output for the currents you need; if you do not plan to charge the battery with a current higher than 6A, then a 6.3A fuse will be enough for you.
Also, to protect your battery and charger, I recommend installing mine or, which, in addition to protection against polarity reversal, will protect the charger from connecting dead batteries with a voltage of less than 10.5V.
Well, in principle, we looked at the charger circuit for the KU202.
Printed circuit board of the thyristor charger on KU202
Assembled from Sergei
Good luck with your repetition and I look forward to your questions in the comments.
For safe, high-quality and reliable charging of any types of batteries, I recommend
In order not to miss the latest updates in the workshop, subscribe to updates in In contact with or Odnoklassniki, you can also subscribe to email updates in the column on the right
Don’t want to delve into the routine of radio electronics? I recommend paying attention to the proposals of our Chinese friends. For a very reasonable price you can purchase quite high-quality chargers
A simple charger with an LED charging indicator, green battery is charging, red battery is charged.
There is short circuit protection and reverse polarity protection. Perfect for charging Moto batteries with a capacity of up to 20A/h; a 9A/h battery will charge in 7 hours, 20A/h in 16 hours. The price for this charger is only 403 rubles, free delivery
This type of charger is capable of automatically charging almost any type of 12V car and motorcycle batteries up to 80A/H. It has a unique charging method in three stages: 1. Constant current charging, 2. Constant voltage charging, 3. Drop charging up to 100%.
There are two indicators on the front panel, the first indicates the voltage and charging percentage, the second indicates the charging current.
Quite a high-quality device for home needs, the price is just RUR 781.96, free delivery. At the time of writing these lines number of orders 1392, grade 4.8 out of 5. Eurofork
Charger for a wide variety of 12-24V battery types with current up to 10A and peak current 12A. Able to charge Helium batteries and SA\SA. The charging technology is the same as the previous one in three stages. The charger is capable of charging both automatically and manually. The panel has an LCD indicator indicating voltage, charging current and charging percentage.
A good device if you need to charge all possible types of batteries of any capacity, up to 150Ah
The price for this miracle 1,625 rubles, delivery is free. At the time of writing these lines, the number 23 orders, grade 4.7 out of 5. When ordering, do not forget to indicate Eurofork
Now there is no point in assembling a charger for car batteries yourself: there is a huge selection of ready-made devices in stores, and their prices are reasonable. However, let’s not forget that it’s nice to do something useful with your own hands, especially since a simple charger for a car battery can be assembled from scrap parts, and its price will be a pittance.
The only thing you should immediately warn about is that circuits without precise regulation of the current and voltage at the output, which do not have a current cutoff at the end of charging, are suitable for charging only lead-acid batteries. For AGM and the use of such charges leads to damage to the battery!
How to make a simple transformer device
The circuit of this transformer charger is primitive, but functional and assembled from available parts - the simplest type of factory chargers are designed in the same way.
At its core, this is a full-wave rectifier, hence the requirements for the transformer: since the voltage at the output of such rectifiers is equal to the rated AC voltage multiplied by the root of two, then with 10V on the transformer winding we get 14.1V at the output of the charger. You can take any diode bridge with a direct current of more than 5 amperes or assemble it from four separate diodes; a measuring ammeter is also selected with the same current requirements. The main thing is to place it on a radiator, which in the simplest case is an aluminum plate with an area of at least 25 cm2.
The primitiveness of such a device is not only a disadvantage: due to the fact that it has neither adjustment nor automatic shutdown, it can be used to “reanimate” sulfated batteries. But we must not forget about the lack of protection against polarity reversal in this circuit.
The main problem is where to find a transformer of suitable power (at least 60 W) and with a given voltage. Can be used if a Soviet filament transformer turns up. However, its output windings have a voltage of 6.3V, so you will have to connect two in series, winding one of them so that you get a total of 10V at the output. An inexpensive transformer TP207-3 is suitable, in which the secondary windings are connected as follows:
At the same time, we unwind the winding between terminals 7-8.
Simple electronically regulated charger
However, you can do without rewinding by adding an electronic output voltage stabilizer to the circuit. In addition, such a circuit will be more convenient for garage use, since it will allow you to adjust the charge current during power supply voltage drops; it is also used for small-capacity car batteries, if necessary.
The role of the regulator here is played by the composite transistor KT837-KT814, the variable resistor regulates the current at the output of the device. When assembling the charger, the 1N754A zener diode can be replaced with the Soviet D814A.
The variable charger circuit is easy to replicate and can be easily assembled without the need to etch the printed circuit board. However, keep in mind that field-effect transistors are placed on a radiator, the heating of which will be noticeable. It is more convenient to use an old computer cooler by connecting its fan to the outputs of the charger. Resistor R1 must have a power of at least 5 W; it is easier to wind it from nichrome or fechral yourself or connect 10 one-watt 10 ohm resistors in parallel. You don’t have to install it, but we must not forget that it protects the transistors in the event of a short circuit.
When choosing a transformer, focus on an output voltage of 12.6-16V; take either a filament transformer by connecting two windings in series, or select a ready-made model with the desired voltage.
Video: The simplest battery charger
Remaking a laptop charger
However, you can do without searching for a transformer if you have an unnecessary laptop charger at hand - with a simple modification we will get a compact and lightweight switching power supply capable of charging car batteries. Since we need to get an output voltage of 14.1-14.3 V, no ready-made power supply will work, but the conversion is simple.
Let's look at a section of a typical circuit according to which devices of this kind are assembled:
In them, maintaining a stabilized voltage is carried out by a circuit from the TL431 microcircuit that controls the optocoupler (not shown in the diagram): as soon as the output voltage exceeds the value set by resistors R13 and R12, the microcircuit lights up the LED of the optocoupler, tells the PWM controller of the converter a signal to reduce the duty cycle of the supplied to the pulse transformer. Difficult? In fact, everything is easy to do with your own hands.
Having opened the charger, we find not far from the output connector TL431 and two resistors connected to the Ref. It is more convenient to adjust the upper arm of the divider (resistor R13 in the diagram): by decreasing the resistance, we reduce the voltage at the output of the charger; by increasing it, we raise it. If we have a 12 V charger, we will need a resistor with a higher resistance, if the charger is 19 V, then with a smaller one.
Video: Charging for car batteries. Protection against short circuit and reverse polarity. With your own hands
We unsolder the resistor and instead install a trimmer, pre-set on the multimeter to the same resistance. Then, having connected a load (a light bulb from a headlight) to the output of the charger, we turn it on to the network and smoothly rotate the trimmer motor, while simultaneously controlling the voltage. As soon as we get the voltage within 14.1-14.3 V, we disconnect the charger from the network, fix the trimmer resistor slide with nail polish (at least for nails) and put the case back together. It will take no more time than you spent reading this article.
There are also more complex stabilization schemes, and they can already be found in Chinese blocks. For example, here the optocoupler is controlled by the TEA1761 chip:
However, the setting principle is the same: the resistance of the resistor soldered between the positive output of the power supply and the 6th leg of the microcircuit changes. In the diagram shown, two parallel resistors are used for this (thus obtaining a resistance that is outside the standard series). We also need to solder a trimmer instead and adjust the output to the desired voltage. Here is an example of one of these boards:
By checking, we can understand that we are interested in the single resistor R32 on this board (circled in red) - we need to solder it.
There are often similar recommendations on the Internet on how to make a homemade charger from a computer power supply. But keep in mind that all of them are essentially reprints of old articles from the early 2000s, and such recommendations are not applicable to more or less modern power supplies. In them it is no longer possible to simply raise the 12 V voltage to the required value, since other output voltages are also controlled, and they will inevitably “float away” with such a setting, and the power supply protection will work. You can use laptop chargers that produce a single output voltage; they are much more convenient for conversion.
Analysis of more than 11 circuits for making a charger with your own hands at home, new circuits for 2017 and 2018, how to assemble a circuit diagram in an hour.
TEST:
To understand whether you have the necessary information about batteries and chargers for them, you should take a short test:- What are the main reasons why a car battery discharges on the road?
A) The motorist got out of the vehicle and forgot to turn off the headlights.
B) The battery has become too hot due to exposure to sunlight.
- Can the battery fail if the car is not used for a long time (sitting in a garage without starting)?
A) If left idle for a long time, the battery will fail.
B) No, the battery will not deteriorate, it will only need to be charged and it will function again.
- What current source is used to recharge the battery?
A) There is only one option - a network with a voltage of 220 volts.
B) 180 Volt network.
- Is it necessary to remove the battery when connecting a homemade device?
A) It is advisable to remove the battery from its installed location, otherwise there is a risk of damaging the electronics due to high voltage.
B) It is not necessary to remove the battery from its installed location.
- If you confuse “minus” and “plus” when connecting a charger, will the battery fail?
A) Yes, if connected incorrectly, the equipment will burn out.
B) The charger simply will not turn on; you will need to move the necessary contacts to the correct places.
Answers:
- A) Headlights not turned off when stopping and sub-zero temperatures are the most common causes of battery discharge on the road.
- A) The battery fails if it is not recharged for a long time when the car is idle.
- A) For recharging, a mains voltage of 220 V is used.
- A) It is not advisable to charge the battery with a homemade device if it is not removed from the car.
- A) The terminals should not be mixed up, otherwise the homemade device will burn out.
Battery on vehicles require periodic charging. The reasons for the discharge can be different - from headlights that the owner forgot to turn off, to negative temperatures outside in winter. For recharge battery You will need a good charger. This device is available in large varieties in auto parts stores. But if there is no opportunity or desire to purchase, then memory You can do it yourself at home. There are also a large number of schemes - it is advisable to study them all in order to choose the most suitable option.
Definition: A car charger is designed to transmit electric current with a given voltage directly to Battery
Answers to 5 Frequently Asked Questions
- Will I need to take any additional measures before charging the battery in my car?– Yes, you will need to clean the terminals, since acid deposits appear on them during operation. Contacts It needs to be cleaned very well so that current flows to the battery without difficulty. Sometimes motorists use grease to treat terminals; this should also be removed.
- How to wipe charger terminals?— You can buy a specialized product in a store or prepare it yourself. Water and soda are used as a self-made solution. The components are mixed and stirred. This is an excellent option for treating all surfaces. When the acid comes into contact with soda, a reaction will occur and the motorist will definitely notice it. This area will need to be thoroughly wiped to get rid of all acids. If the terminals were previously treated with grease, it can be removed with any clean rag.
- If there are covers on the battery, do they need to be opened before charging?— If there are covers on the body, they must be removed.
- Why is it necessary to unscrew the battery caps?— This is necessary so that the gases formed during the charging process can freely exit the case.
- Is there a need to pay attention to the electrolyte level in the battery?- This is done without fail. If the level is lower than required, then you need to add distilled water inside the battery. Determining the level is not difficult - the plates must be completely covered with liquid.
It’s also important to know: 3 nuances about operation
The homemade product differs somewhat in its method of operation from the factory version. This is explained by the fact that the purchased unit has built-in functions, helping in work. They are difficult to install on a device assembled at home, and therefore you will have to adhere to several rules when operation.
- A self-assembled charger will not turn off when the battery is fully charged. That is why it is necessary to periodically monitor the equipment and connect it to multimeter– for charge control.
- You need to be very careful not to confuse “plus” and “minus”, otherwise Charger will burn.
- The equipment must be turned off when connecting to charger.
By following these simple rules, you will be able to recharge correctly battery and avoid unpleasant consequences.
Top 3 charger manufacturers
If you don’t have the desire or ability to assemble it yourself memory, then pay attention to the following manufacturers:
- Stack.
- Sonar.
- Hyundai.
How to avoid 2 mistakes when charging a battery
It is necessary to follow the basic rules in order to properly nourish battery by car.
- Direct to mains battery connection is prohibited. Chargers are intended for this purpose.
- Even device it is made with high quality and from good materials, you will still need to periodically monitor the process charging, so that troubles don't happen.
Following simple rules will ensure reliable operation of self-made equipment. It is much easier to monitor the unit than to spend money on components for repairs.
The simplest battery charger
Scheme of a 100% working 12 volt charger
Look at the diagram in the picture memory at 12 V. The equipment is intended for charging car batteries with a voltage of 14.5 Volts. The maximum current received during charging is 6 A. But the device is also suitable for other batteries - lithium-ion, since the voltage and output current can be adjusted. All the main components for assembling the device can be found on the Aliexpress website.
Required components:
- dc-dc buck converter.
- Ammeter.
- Diode bridge KVRS 5010.
- Hubs 2200 uF at 50 volts.
- transformer TS 180-2.
- Circuit breakers.
- Plug for connecting to the network.
- "Crocodiles" for connecting terminals.
- Radiator for diode bridge.
Transformer any one can be used at your 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 of the charger circuit Dawn 2. It is compiled according to the original Memory If you master this scheme, you will be able to independently create a high-quality copy that is no different from the original sample. Structurally, the device is a separate unit, closed with a housing to protect the electronics from moisture and exposure to bad weather conditions. It is necessary to connect a transformer and thyristors on the radiators to the base of the case. You will need a board that will stabilize the current charge and control the thyristors and terminals.
1 smart memory circuit
Look at the picture for a circuit diagram of a smart charger. The device is necessary for connection to lead-acid batteries with a capacity of 45 amperes per hour or more. This type of device is connected not only to batteries that are used daily, but also to those on duty or in reserve. This is a fairly budget version of the equipment. It does not provide indicator, and you can buy the cheapest microcontroller.
If you have the necessary experience, then you can assemble the transformer yourself. There is also no need to install audible warning signals - if battery connects incorrectly, the discharge lamp will light up to indicate an error. The equipment must be equipped with a switching power supply of 12 volts - 10 amperes.
1 industrial memory circuit
Look at the industrial diagram charger from Bars 8A equipment. Transformers are used with one 16-volt power winding, several vd-7 and vd-8 diodes are added. This is necessary in order to provide a bridge rectifier circuit from one winding.
1 inverter device diagram
Look at the picture for a diagram of an inverter charger. This device discharges the battery to 10.5 Volts before charging. The current is used with a value of C/20: “C” indicates the capacity of the installed battery. After that process the voltage rises to 14.5 Volts using a discharge-charge cycle. The ratio of charge and discharge is ten to one.
1 electrical circuit charger electronics
1 powerful memory circuit
Look at the picture at the diagram of a powerful charger for a car battery. The device is used for acidic battery, having high capacity. The device easily charges a car battery with a capacity of 120 A. The output voltage of the device is self-regulated. It ranges from 0 to 24 volts. Scheme It is notable for the fact that it has few components installed, but it does not require additional settings during operation.
Many could already see the Soviet Charger. It looks like a small metal box and may seem quite unreliable. But this is not true at all. The main difference between the Soviet model and modern models is reliability. The equipment has structural capacity. In the event that to the old device connect the electronic controller, then charger it will be possible to revive. But if you no longer have one at hand, but there is a desire to assemble it, you need to study the diagram.
To the features their equipment includes a powerful transformer and rectifier, with the help of which it is possible to quickly charge even a very discharged battery. Many modern devices will not be able to reproduce this effect.
Electron 3M
In an hour: 2 do-it-yourself charging concepts
Simple circuits
1 the simplest scheme for an automatic charger for a car battery
