Chargers schemes

For (sealed, maintenanceable) batteries.

Batteries manufactured using GEL and AGM technologies are structurally lead-acid batteries, they consist of a similar set of compound parts - in the plastic body of the plate-electrodes from lead or its alloys, are immersed in an acidic medium - electrolyte, as a result of chemical reactions between the electrodes And the electrolyte is produced by electric current. When the external electrical voltage is supplied to the terminals of lead plates, inverse chemical processes occur, as a result of which the battery restores its initial properties, i.e. Charged.

Rechargeable Battery Technology AGM (Absorbent Glass Mat) - the difference between these batteries from the classic in that they contain no liquid, and the absorbed electrolyte, this gives a number of changes in the properties of the battery.
Sealed, maintenanceable batteries produced using AGM technology, work perfectly in buffer mode, i.e. In recharging mode, in this mode they serve until 10-15 years (AKB-12V). If they are used in cyclic mode (i.e., constantly charge-discharge at least 30% -40% of the tank), then their service life is reduced. Almost all hermetic batteries can be installed on their side, but the manufacturer usually recommends installing batteries in the "normal", vertical position.
AGM General Purpose Batteries are commonly used in low-cost UPSs (uninterrupted), and backup power supply systems, that is, where the batteries are mainly located in the recharge mode, and sometimes, during the power supply in power supply, they give stored energy.
AGM batteries usually have a maximum allowed charge current 0.3C, and the final charge voltage is 14.8-15V.

Disadvantages:
Should not be stored in a discharged state, the voltage should not fall below 1.8V;
Extremely sensitive to exceeding the charge voltage;

Batteries made according to this technology are often confused with accumulators manufactured using GEL technology (in which the electrolyte is a jelly-like, which have a number of advantages).

Rechargeable Battery Technology Gel (GEL ELECTROLITE) - contain electrolyte thickened in the jelly-like state, this gel does not give electrolyte to evaporate, the pairs of oxygen and hydrogen are held inside the gel, react and turn into water that absorbs gel. Almost all evaporations are thus returned back to the battery, and this is called gas recombination. Such technology allows you to use a constant amount of electrolyte without a water additive for the entire service life. rechargeable battery, and its increased resistance to the discharge current does not allow "harmful" non-destructive lead sulphates.
Gel batteries have about 10-30% longer service life than AGM batteries and better withstand cyclic charge-discharge modes, also, they are less painfully tolerated deep discharge. Such batteries are recommended to be used where it is necessary to ensure a long service life at deeper discharge modes.
Due to its characteristics, gel batteries can be discharged long, have a low self-discharge, they can be operated in a residential room and almost in any position.
Most often, such batteries for 6V or 12V voltage are used in computers backup blocks (UPS), security and measuring systems, lanterns and other devices requiring autonomous power. The disadvantages include the need for strict compliance with charge regimes.
As a rule, when charging such batteries, the charge current is set to 0.1C, where C is the battery capacity, and the charging current is limited and the voltage is stabilized and installed within 14-15 volts. In the process of charge, the voltage remains almost unchanged, and the current is reduced from the installed, to the value of 20-30m at the end of the charge. Such batteries are produced by many manufacturers, and their parameters may differ and, above all, according to the maximum permissible charging current, so before use it is desirable to study the documentation of the specific copy of the AKB.

To charge the batteries manufactured using GEL and AGM technology, it is necessary to use a special charger with the corresponding charge parameters other than the charge of classic batteries with a liquid electrolyte.

Further, a selection of various schemes for the charge of such batteries is proposed and if you take about 0.1 from its capacitance to the rule, it can be said that you can charge the batteries of almost any manufacturers offered charger.

Fig.1 Photo of battery 12V (7.2A / h).

Charger diagram on L200C chip There is a voltage stabilizer with a programmable output current limiter.



Fig.2 Charger scheme.

The power of the resistors R3-R7 of the switching current of the charge must be no less than specified in the diagram, but better.
The chip, you need to install on the radiator, and the easier it will be its thermal mode, the better.
R2 resistor is needed to adjust the output voltage in the range of 14-15 volts.
Voltage on the secondary winding of the transformer 15-16 volts.

Everything works like this - at the beginning of the charge, the current is large, and by the end it is lowered to the minimum, as a rule, manufacturers to preserve the capacity of the AKB recommends just such a minor current for a long time.

Fig.3 Card of the finished device.

Charger diagram, the basis of which is the integrated stabilizers of voltage KR142EN22Uses the "charge constant voltage with a current limitation" and is calculated for charging various types of batteries.



The scheme works like this: first the rated current is supplied to the discharged battery, and then the voltage on the battery is growing, and the current remains unchanged, when the installed voltage threshold is reached, its further growth is stopped, and the current begins to decline.
By the time of the charge, the charging current is equal to the self-discharge current, in such a state of the battery may be in the charger as much as possible without reloading.

Charger Created as universal and intended for charging 6 and 12 volt batteries of the most common containers. The device uses integral stabilizers KR142EN22, the main advantage of which is the low voltage difference input / output (for kr142en22, this voltage is 1.1V).

Functionally, the device can be divided into two parts, the maximum current limit node (DA1.R1-R6) and voltage stabilizer (DA2, R7-R9). Both of these parts are made according to typical schemes.
The SB1 switch selects the maximum charging current, and the SB2 switch the final voltage per battery.
At the same time, when charging 6V AKB section SB2. 1 Switches the secondary winding of the transformer, reducing the voltage.
To reduce the charge time, the initial charging current can reach 0.25C, (some battery manufacturers allow maximum charging current to 0.4C).

Details:
Since the device is designed for a long continuous operation, then at the power of the current resistors R1-R6, it should not be saved, and in general, all elements are desirable to choose with a margin. In addition to increasing reliability, it will improve the thermal mode of the entire device.
Strip resistors are desirable to take multi-turn SP5-2, SP5-3 or their analogues.
Capacitors: C1 - K50-16, K50-35 or imported analogue, C2, SZ can apply metal-filled type K73 or, ceramic K10-17, km-6. Imported 1N5400 (3a, 50v) diodes, if there is free space in the case, it is desirable to replace domestic in metal housings Type D231, D242, KD203, etc.
These diodes dissect warmly warm with their housings, and when working in this device Their heating is almost impaired.
The lowering transformer must provide the maximum charging current for a long time without overheating. Voltage on winding II is 12V (charge of 6-volt batteries). The voltage on the winding III is included in series with winding II when charging 12-volt batteries - 8V.
In the absence of chip KR142EN22, it is possible to install KR142EN12, but it is necessary to consider that the output voltages on the secondary windings of the transformer will have to be increased by 5V. In addition, you will have to install diodes that protect chips from feedbacks.

Device setting should be started with the installation of resistors R7 and R8 required voltages at the output terminals of the device without connecting the load. The R7 resistor is set to the voltage within 14.5 ... 14.9V for charge of 12-volt batteries, and R8-7.25 ... 7,45V for 6-volt. Then, by connecting the load resistor with a resistance of 4.7 Ohms and with a power of at least 10w in the charge mode of 6-volt batteries, check the output current ammeter with all SB1 switch positions.

Option device for charge AKB12V-7.2AH,the scheme is the same as the previous one, only one of it is excluded switches SB1, SB2 with additional resistors and a transformer without taps is applied..




Customize the same as described above: First, the R3 resistor without connecting the load is set to the output voltage in the range of 14.5 ... 14.9v, and then with a connected load, the selection of the resistor R2, the output current is set 0.7 ... 0 , 8a.
For other types of AKB, you need to select resistors R2, R3 and a transformer in accordance with the voltage and capacity of the charge battery.
Charging parameters should be chosen based on the condition i \u003d 0.1C, where C is the battery capacity, and the voltage is 14.5 ... 14.9V (for 12 volt batteries).

When working with these devices, you first set the necessary charging current and voltage values, then the battery and the device are connected to the network. In some cases, the ability to select a charging current allows you to speed up the charge by setting the current more than 0.1c. Thus, for example, an acb with a capacity of 7,2A / h can be charged with a current of 1,5a not exceeding the maximum allowable charging current 0.25С.

Integral voltage stabilizer KR142EN12 (LM317) allows you to create a simple stable current source,
a chip in such an inclusion is a current stabilizer and regardless of the connected battery gives only a calculated current - the voltage is set "automatically".



The advantages of the proposed device.
Not afraid of short circuits; It does not matter the number of elements in the charging battery and their type - can be charged and acidic sealed 12.6V and lithium 3.6V and alkaline 7.2V. The current switch should be included as shown in the diagram - so that with any manipulations, the R1 resistor remains connected.
Charging current is calculated as follows: i (in amperes) \u003d 1.2V / R1 (in Omah). To indicate the current used transistor (Germany), allowing you to visually observe currents up to 50 mA.
The maximum stress of the charged battery should be less than the supply voltage (charging), 4V; In the case of charge with a maximum current 1a, the chip 142812 should be installed on a radiator scattering at least 20w.
Charging current 0.1 from the tank is suitable for any types of batteries. To fully charge the battery, it needs to give 120% of the nominal charge, but before that it should be completely discharged. Consequently, charging time in the recommended mode is 12 hours.

Details:
D1 diode and fuse F2 protect the memory from improper inclusion of the battery. Capacity C1 is selected from the ratio: 1 amp is needed 2000 microf.
Rectifier bridge - at least 1a and voltage over 50V. Transistor - Germany due to small opening voltage B e. R3-R6 resistor rates are determined. Chip KR142EN12 Replace for any analogues that hold the specified current. Transformer power - at least 20w.

Simple charger on LM317, scheme as in the description (Datasheet), add only some elements, and get a charger.



The VD1 diode is added so that the charged battery can be discharged in the event of a power loss, the voltage switch is still added. The charge current is set in the area of \u200b\u200b0.4a, the transistor VT1- 2N2222 can be replaced by KT3102, the switch S1 of any into two positions, transformer 15V, diode bridge on 1N4007.
The charge current is set (1/10 from the battery capacity) with the help of a resistor R7, calculated by the formula R \u003d 0.6 / I ZA.
In this example, it is R7 \u003d 0.6 / 0.4 \u003d 1.5. Power 2 W.

Setup.
We connect to the network, exhibit the required voltages, for AKB-6V, the charge voltage is 7.2V-7.5V, for AKB-12V - 14.4-15V, is set to resistors R3, R5, respectively.

Charger with automatic shutdown To charge 6V hermetic lead battery, with minimal changes, you can also be applied to charge other types of batteries, with any voltage for which the calculation of the charge is the achievement of a certain voltage level.
In this device, the battery charge stops when the voltage is reached at 7.3V terminals. The charge is carried out not by stabilized current limited at the level of 0.1C resistor R5. The voltage level in which the device stops the charge, set by the VD1 stabitron with an accuracy of the tenth of volt.
The basis of the scheme is the operational amplifier (OU), included as a comparator and connected by the inverting input to the source of the exemplary voltage (R1-VD1), and not inverting the battery. As soon as the battery voltage exceeds the sample voltage, the comparator will switch to a single state, the T1 transistor opens and the relay K1 will turn off the battery from the voltage source, simultaneously give a positive voltage to the T1 transistor. Thus, T1 will be open and its condition will no longer depend on the voltage level at the output of the comparator. The comparator itself is covered by positive feedback (R2), which creates hysteresis and leads to a sharp, jump-shaped switching and opening the transistor. Due to this scheme, the scheme is delivered from the lack of similar devices with a mechanical relay, in which the relay emits an unpleasant rattling sound due to the fact that the contacts are balanced at the border of the switch, but the inclusion does not occur yet. In case of disabling network voltage, the device will resume work as soon as it appears and will not allow the rearness of the AKB.



The device collected from serviceable parts begins to work immediately and does not need the setup. The operating amplifier indicated in the diagram can operate in the range of supply voltages from 3 to 30 volts. The disconnection voltage depends only on the parameters of Stabitron. When connecting the battery with another voltage, for example, 12V, the VD1 stabilitron must be chosen by stabilization voltage, (on the voltage of the charged battery - 14.4 ... 15v).

Charger for lead acidic hermetic batteries.
The current stabilizer contains only three parts: an integral voltage stabilizer DA1 type KR142EN5A (7805), HL1 LED and resistor R1. The LED, in addition to working in the current stabilizer, also performs the battery charge indicator function. The battery charge is performed by direct current.



The alternating voltage from the TP1 transformer enters the diode bridge VD1, the current stabilizer (DA1, R1, VD2).
Setting the scheme is reduced to the adjustment of the battery charge current. The charging current (in amperes) is usually chosen ten times less than the numerical values \u200b\u200bof the battery capacity (in amps-hours).
To configure, instead of the battery, you need to connect the ammeter to the current 2 ... 5a and the selection of the resistor R1 to set the desired charge current on it.
The DA1 microcircuit must be installed on the radiator.
Resistor R1 consists of two consecutively connected wire resistors 12w power.

Dual-mode charger.
The proposed diagram of the charger for battery batteries 6V, combines the advantages of two main types of chargers: constant voltage And DC, each of which has its advantages.



The basis of the circuit is the voltage regulator on the LM317T and the controlled TL431 stabilion.
In DC mode, the R3 resistor sets the current 370 mA, diode D4 prevents the battery discharge via LM317T when the network voltage disappears, the R4 resistor provides unlocking the VT1 transistor when the network voltage is removed.
Controlled TL431 stabilion, R7, R8 resistors, and R6 potentiometer form a circuit defining the battery charge to a given voltage. VD2 LED - Network Indicator, VD3 LED lights up in constant voltage mode.

Simple automatic charger, It is intended to charge the batteries 12 volts with a voltage battery, designed for continuous round-the-clock operation with power supply from a voltage of 220V, charge is carried out by a small pulse current (0.1-0.15 a).
When the battery is properly connected, a green device indicator should turn around. The lack of a green LED glow speaks of a complete charge of a battery or a lines break. In this case, the red device indicator (LED) lights up.



The device provides protection from:
Short circuit in line;
Short circuit in the battery itself.
Incorrect connection of the polarity of the battery;
Adjustment lies in the selection of resistances R2 (1.8K) and R4 (1.2k) until the glow of the green LED disappears, at a voltage on a 14.4V battery.

CHARGER Provides stabilized load current and is intended to charge motorcycle batteries with a rated voltage of 6-7V. The charge current is smoothly adjusted within 0-2a, variable resistor R1.
The stabilizer is assembled on a composite transistor VT1, VT2, Stabilitron VD5 fixes the voltage between the base and emitter of the compound transistor, with the result that the VT1 transistor connected in series with the load supports practically d.C. Charge, regardless of the change of EDF battery in the process of charge.



The device is a current generator with a large internal resistance, so it is not afraid of short circuits, the voltage is removed from the R4 resistor feedback for current, limiting current through the VT1 transistor when short closure In the load chain.

Charger Charger Charger Based on the titiisttor phase pulse power regulator, does not contain scarce details, and with obviously good elements does not require setup.
The charging current is close to the impulse, which is considered to contribute to the extension of the battery life.
The disadvantage of the device is vibrations of the charging current at the unstable voltage of the electrical system, and as all the similar thyristor phase pulse controls, the device creates interference with the radio. To combat them should provide a network LC filter, similar to those used in network pulse blocks Nutrition.



The scheme is a traditional thyristor power regulator with phase-pulse control, powered by winding II lower transformer through the diode bridge VD1-VD4. The thyristor control unit is made on an analogue of a single-pass transistor VT1, VT2. The time during which the C2 capacitor charges before switching the single-pass transistor, can be adjusted by a variable resistor R1. With extreme right, according to the position of the position of its engine, the charging current will be maximal and vice versa. The VD5 diode protects the control circuit from the reverse voltage that occurs when the vs1 thyristor is turned on.

Details of the device In addition to the transformer, rectifier diodes, a variable resistor, a fuse and thyristor, are placed on the printed circuit board.
Condensatory C1-K73-11 with a capacity of 0.47 to 1 μF or K73-16, K73-17, K42U-2, MBGP. VD1-VD4 diodes any on the direct current 10a and the reverse voltage of at least 50V. Instead of thyristor KU202V, CU202G-CU202E is suitable, will work normally and powerful T-160, T-250.
The CT361A transistor will be replaced by CT361B KT361E, CT3107A KT502B CT502G KT501G, and CT315A on CT315B-CT315D CT312B KT3102A KT503B-KT503G. Instead of KD105B CD105V CD105G or D226 with any letter index.
A variable resistor R1 - SGM, SPZ-30A or SPO-1.
Network lowering transformer required power with a secondary winding voltage from 18 to 22V.
If the voltage in the transformer on the secondary winding of more than 18V resistor R5 should be replaced by another larger resistance (at 24-26V to 200 ohms). In the case when secondary winding The transformer has a removal from the middle or two identical windings, the rectifier is better to perform on two diodes according to the standard two-way diagram.
With a secondary winding voltage of 28 ... 36v, it is possible to completely abandon the rectifier - its role will simultaneously perform a thyristor VS1 (straightening - single-alterogeneous). For such an embodiment, it is necessary between the output 2 of the fees and the plus wire to include the separation diode KD105B or D226 with any letter index (cathode to the board).
In this case, only those that allow working with reverse voltage can be used as a thyristor, for example, CU202E.

Battery protection from deep discharge.

Such a device with a decrease in the voltage to the battery to the minimum permissible value, automatically turns off the load. Devices can be used wherever batteries are used, and where there is no constant monitoring of the status of the battery, that is, where it is important to prevent the processes related to their deep discharge.

Slightly modified primary source scheme:

Schemes for service functions:
1. When the voltage is reduced to 10.4V occurs full shutdown Loads and battery control schemes.
2. The voltage of the comparator's response can be adjusted for a specific type of battery.
3. After an emergency shutdown, the re-inclusion is possible at a voltage above 11V, by pressing the "ON" button.
4. If there is a need to disable the load manually, it is enough to press the "OFF" button.
5. In case of no compliance with polarity when connecting to the battery (ransoms), the control device and the connected load are not included.

As a rapid resistor, the use of resistors of any nominal from 10 kΩ to 100 com.
In the scheme used operational amplifier LM358N, the domestic analogue of which is kr1040ud1.
Stabilizer 78L05 to voltage 5V, can be replaced by any similar, for example, kr142en5a.
Relay JZC-20F on 10a 12V, it is possible to use other similar relays.
The CT817 transistor can be replaced by KT815 or other similar to the corresponding conductivity.
Diode can use any low-power, able to withstand the current of the relay winding.
Buttons without fixing different colors, green on inclusion, red - on shutdown.

Adjustment is to install the desired threshold of the disconnection of the relay, collected without errors and from the serviceable parts the device begins to work immediately.

The following device for protecting 12V batteries with a capacity of up to 7.5A / h from deep discharge and short circuit with automatic shutdown His exit from the load.





CHARACTERISTICS
The voltage on the battery at which it turns off - 10 ± 0.5V.
The current consumed by the battery device in the on state, not more than - 1ma
Current consumed by the device from the battery in the off state, not more - 10MK
The maximum permissible constant current through the device is 5a.
Maximum allowable short-term (5 sec) current through device - 10A
Shutdown time with a short closure at the output of the device, not more than - 100 μs

The order of the device
Connect the device between the battery and the load in the following sequence:
- Connect terminals on wires, observing the polarity (red wire +), to the battery,
- Connect to the device by observing the polarity (plus terminal marked with a +) icon), load terminals.
In order to appear at the output of the device, the voltage should be briefly closed the minus output to the minus input. If the load besides the battery, another source feeds, then this is not necessary.

The device works as follows;
When switching to battery powered, the load discharges it to the response voltage of the protection device (10 ± 0.5V). When this value is reached, the device turns off the battery from the load, preventing its further discharge. Turning on the device will occur automatically when the voltage load is supplied to the battery charge.
With a short closure in the load, the device also disables the battery from the load, its turning on it automatically if the load from the load side is more than 9.5V. If there is no such voltage, then you must briefly move the output minus device terminal and minus battery. Resistors R3 and R4 are set to the trigger threshold.

1. PCBs in Lay format Sprint Layout) -

When you want to charge a lead battery of medium and small sizes (not automotive), then most often take a regular power supply or a simple transformer with a rectifier, after which the battery is connected to it by 10, pick up 0.1C. This is of course the collective farm. In more or less decent devices where the "level" filling is required with all tracking and automatic charge control systems. For this purpose and intended this scheme Charger based on the BQ24450 chip from Texas tools. This microcircuit takes all functions to charge the battery and maintain the stability of the process, regardless of the conditions and state of the battery. BUT wide range Charging currents and stress makes it suitable for batteries of emergency lighting, radio-controlled cars, motorcycles, boats, or any other vehicle with 6 - 12 in the battery - just connect this charger to the battery and that's it.

Characteristics of the BQ24450 chip

• Entry 10-40 V DC
• Load current (charge) 0.025-1 A
• With an external transistor - up to 15 a
• Voltage and current adjustment during charging
• Temperature and compensated source of reference voltage

The BQ24450 microcircuit contains all the necessary elements to optimally monitor the charging of lead-acid batteries. It controls the charging current, as well as charging voltage to safely and efficiently charge the battery, increasing the efficient battery capacity and service life. Built-in precision source of reference voltage with temperature compensation to track the characteristics of lead-acid cells supports the optimal charging voltage in the extended temperature range without the use of any external components.

The low current consumption of the chip allows you to accurately monitor the process due to a small self-dissemination. There are comparators that track the charging voltage and current. These comparators feed on the internal source, which positively affects the stability of the charging cycle. Talk to:

The need for a charger for lead-cylinder batteries has arisen a long time ago. The first charger was made more for a car battery at 55A.C. Over time, the farm has maintained helium batteries of various denominations, which also need to be charged. For each battery, a separate charger is at least unreasonable. Therefore, I had to take in the hands of a pencil, to shut the available literature, mostly the magazine "Radio", and together with comrades to give birth to the concept of a universal automatic charger (UAZ) for 12 volt batteries from 7 hour to 60 hour. The resulting design I reap on your court. Made in hardware more than 10 pcs. With various variations. All devices operate without complaints. The scheme is easily repeated with minimal settings.
As a basis, the power supply was immediately taken from the old PC of the AT format, since it has a whole complex of positive qualities: small sizes and weight, good stabilization, power with a large margin, and the most important thing is the ready-made power part to which the control unit remains to fasten. The idea of \u200b\u200bthe bu sucks S. heads in his article "Automatic charger for lead-acid battery", Magazine "Radio" No. 12 2004, thank you separately.
Briefly repeat the battery charging algorithm. The whole process consists of three stages. At the first stage, when the battery is fully or partially discharged, it is permissible to carry out a large current reaching 0.1 :.0.2С, where C is the battery capacity in amps-hours. The charging current must be limited from above the specified value or stabilized. As the charge accumulates, the voltage is growing at the battery terminals. This voltage is controlled. Upon reaching the level of 14.4 - 14.6 volts, the first stage is completed. In the second stage, it is necessary to maintain a constant voltage achieved and control the charging current that will decrease. When the charge current falls to 0.02s, the battery will take a charge at least 80%, go to the third stage final. Reduce charge voltage up to 13.8 V. and support it at this level. The charge current will gradually decrease to 0.002 :.0.001c and stabilizes on this value. Such a battery current is not dangerous, in this mode the battery may be long, without harming for itself and is always ready for use.
Now we will talk about how this is all done. BP from the computer was chosen from the considerations of the greatest distribution schedule. The control unit is made on the TL494 chip and its analogues (MB3759, ka7500, KR1114EU4) and slightly converted:

5V, -5V, -12V output voltage schemes are dismantled, feedback resistors 5 and 12V are disappeared, the overvoltage protection scheme is disabled. The scheme fragment marked with a cross-breaking positions of chains. Only the output part 12B is left, you can still replace diode assembly In the chain of 12V on the assembly, removed from the 5-volt chain, it helps, although not necessarily. All extra wires are removed, they left only 4 wires of black and yellow color long centimeters of P10, the output of the power part. To the 1st leg of the chip soldering the wiring long 10 cm. It will be control. This refinement is completed.
In addition, at the request of numerous people who want to have such a thing, the workout mode and the protection circuit against the battery is implemented for particularly inattentive. And so bu:

Main nodes: Parametric reference stabilizer 14,6V VD6-VD11, R21
Block of comparators and indicators implementing three stages of charging battery DA1.2, VD2 first stage, DA1.3, VD5 second, DA1.4, VD3 third.
Stabilizer VD1, R1, C1 and dividers R4, R8, R5, R9, R6, R7 forming the support voltage of comparators. SA1 switch and resistors provide charging mode change for different batteries.
Training unit DD K561L5, VT3, VT4, VT5, VT1, DA1.1.
Protect VS1, DA5, VD13.

How it works. Suppose that we charge the car battery 55Ah. Comparators track the voltage drop on the R31 resistor. At the first stage, the scheme works as a current stabilizer, when the charge current is turned on, there will be about 5a, all 3 LEDs are burning. DA1.2 will keep the charge current while the voltage on the battery does not reach 14,6V., DA1.2 closes, will go out the VD2 red. The second stage began.
At this stage, the voltage of 14.6V on the battery is supported by the stabilizerVD6-VD11, R21, i.e. Zu works in voltage stabilization mode. As the battery charge increases, the current falls and as soon as it drops to 0.02s, DA1.3 will work. Yellow VD5 will go out and the VT2 transistor opens. VD6, VD7 is shunting, the stabilization voltage is dropped to 13.8 V. Switched to the third stage.
Then goes a battery player very small. Since by this moment the battery scored approximately 95-97% of the charge, the current decreases gradually to 0.002c and stabilizes. On the good batteries It may decrease to 0.001c. On this threshold and configured DA1.4. The VD3 LED can go out, although in practice it continues to shine weakly. On this process can be considered complete and use the battery for its intended purpose.

Training mode. With long-term storage of the battery, it is periodically recommended to train, as it can extend the life of old batteries. Since the battery is a very inertial, charge-discharge should last for a few seconds. In the literature there are devices that train batteries with a frequency of 50 Hz, which is sadly affected by its health. The discharge current is approximately the tenth of the charge current. The SA2 switch is shown in the training position, SA2.1 will open SA2.2 closed. The discharge scheme VT3, VT4, VT5, R24, SA2.2, R31 is included and the trigger DA1.1, VT1 is turned on. On the elements of DD1.1 and DD1.2 chip K561LE5, a multivibrator is assembled. He gives meander with a period of 10-12 seconds. The trigger cried, the element DD1.3 is open, the pulses from the multivibrator open and close the transistors VT4 and VT3. The VT3 transistor in the open state shunts the VD6-VD8 diodes blocking charging. Battery discharge current goes through R24, VT4, SA2.2, R31. The battery is 5-6 seconds gets the charge and the same time is discharged with a small current. This process lasts the first and second charging step, then trigger is triggered, DD1.3 is closed, VT4 and VT3 are closed. The third stage passes as usual. In the additional indication of the workout mode, there is no need because the VD2, VD3 and VD5 LEDs are blinking. After the first stage, VD3 and VD5 flashes. At the third stage, VD5 shines not blinking. In the workout mode, the battery charge lasts almost 2 times longer.

Protection. In the first constructions, instead of a thyristor, a diode was stood, which was protected from the reverse current. It works very simply, when properly turned on, the optornel opens a thyristor, you can enable charging. With incorrect, the VD13 LED lights up, change the terminals in places. A thyristor anode and cathode should be soldered by a non-polar capacitor of 50 μF 50 volts or 2 of the ongoing electrolyte 100MKF 50B.

Construction and details. The memory is collected in the BP housing from the computer. Boo is made by laser-iron technology. Picture pCB attached in the archive file, performed in SL4. MLT-025 resistors, R31 resistor - a piece of copper wire. The measuring head of the RAP1 can not be set. Just lying and adapted it. Therefore, the values \u200b\u200bof R30 and R33 depend on the milliammeter. Thyristor KU202 in plastic execution. Actually, the execution is visible on the included photos. The monitor power connector and cable were used to turn on the battery. Charging current selection switch is small for 11 positions, resistors are soldered to it. If the memory will charge only car batteries The switch can not be installed, pushing simply jumper. DA1 - LM339. KD521 diodes or similar. Optron PC817 can be put on another with a transistor executive part. The boiler bu was screwed to an aluminum plate with a thickness of 4 mm. It serves as a radiator for a thyristor and KT829, on it, LEDs are inserted into the holes. The resulting unit is screwed to the front wall of the BP. The memory is not heated, so the fan is connected to BP through the KR140B stabilizer, the voltage is limited to 9V. The fan rotates nasty and practically not heard it.

Adjustment. Initially, we install a powerful diode instead of a thyristor, a powerful diode, not sprinkting VD4 and R20, we select VD8-VD10 stabilions so that the output voltage, without load, was 14,0Volt. Next, we sear the VD4 and R20 and the selection of R8, R9, R6 to set the sills of the operation of comparators. Instead of a battery, we connect a wire variable resistor 10 ohms, install a current of 5 amps, we carry the variable resistor instead of R8, tweak it at a voltage of 14.6V. The VD2 LED should go out. We supply the variable resistor instead of R9, exposing about 150 ohms. Turn on the memory, we increase the load current until DA1.2 works, then begin to reduce the current to a value of 0.1 amp. Then reducing R9 until the DA1.3 comparator will work. The stress on the load should fall to 13.8V and the yellow VD5 LED will go out. We reduce the current up to 0.05 amps, the selection of R6 GASIM VD3. But the best adjustment is best done on a good discharged battery. We supply variable resistors, set them a little more indicated in the diagram, connect the ammeter and voltmeter to the battery terminals and do it at a time. The battery is not highly discharged, then it will be faster and more accurate. Practice has shown that the adjustment is practically no needed if it is accurate to select R31. The addition resistors are also selected easily: with the appropriate load current, the voltage drop on R31 should be 0.5V, 0.4V, 0.3V, 0.2V, 0.15V, 0.1V and 0.07V.
Here, in fact, all. Yes, even if an additional two-pole toggle switch, one half of the diode VD6, and the other stabilitron VD9, will be a memory for 6 volt helium batteries. The charge current must be selected by the smallest SA1 switch. At one of the collected this operation was successfully implemented.

As is known, hermetic lead acid batteries can be constantly connected to the charger, that is, to be in recharging mode. To know when the battery is fully charged, the charger must be equipped with any indicator. Below is one of the variants of the charger equipped with a charge indicator.

Description of the Charger for Lead Acid Batteries

The voltage on the charger circuit is supplied to the terminals X1 and X2 from external source constant voltage (12 ... 20 volts). The charging current enters the indicator of the charging current (LED HL1), the transistor VT1 and the charging voltage. Stabilized charging voltage is connected to the Clems x3 and x4, which are connected to the lead acid battery.

Charging current indicator includes a current sensor (resistor R1), charging current flowing through it creates a voltage drop on it. Due to the voltage drop, the VT1 transistor opens, the indicator is connected - the HL1 LED.

The value of the voltage drop in which the VT1 transistor opens, is set by the resistive divider on the resistances R3 and R4. If charging current less installed level Current (current limit is set by the R4 trimming resistor), the HL1 LED is not lit. With an increase in the charging current, the luminous glow also increases smoothly.

A stabilizer adjustable output voltage LM317 is used as a charging voltage stabilizer. In accordance with the voltage and charging current, the LM317 stabilizer is set to a good heat sink.

R5 stroke resistor adjusts the output voltage at the Clems x3 and x4. For batteries with a nominal voltage 6, the output voltage of the charge should be 6.8 ... 6.9 V, for batteries with a rated voltage 12 to this output voltage will already be 13.6 ... 13.8 V.

It should be noted that the input voltage from the external source of constant voltage should be more voltage at the output of the charger about 5 volts (voltage drop on R6 and LM317).