Many home craftsmen are interested in the question of how to convert a cordless screwdriver into a corded one. This is due to the fact that many people use battery-powered models. But the battery has a limited shelf life, it quickly breaks down and the tool stops working. Buy new battery for a cordless screwdriver it is expensive, since its cost is more than half the cost of the tool itself. And then the idea arises of converting such a tool into a network one so that it can work from a 220 V network.

Why does this problem occur?

After a certain service life, the battery begins to spontaneously discharge, this leads to its gradual destruction, this process is irreversible. Once such a battery fails, it cannot be repaired; it must be replaced with a new one. In addition to the fact that the cost of a new battery is high, you can only buy a high-quality battery from official dealers, and they are not available in all cities.

Modern craftsmen have found a fairly simple and affordable way to solve specified problem, they remake the screwdriver and provide it with power from the mains rather than a battery. Using this option provides a number of advantages:

The corded screwdriver does not require periodic battery charging.

1. You will have no downtime during operation, as there will be no need to periodically charge the battery.
2. The current strength will not drop, as happens when batteries are discharged, therefore the torque of the screwdriver will be constant.
3. If you for a long time If you don't use the tool, you won't go down technical specifications batteries, since there is simply none, because the screwdriver now works from the mains.

You can do this work yourself, there is nothing complicated about it. You must have basic skills to perform similar works and necessary components. In this case, you can make a corded screwdriver from a battery-powered one yourself.

To complete the job you will need:

• old battery from the specified model;
• charger;
• cable of the required length;
• soldering iron;
• solder;
• insulating tape.

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Carrying out refurbishment work

You will need a working charger, to the terminals of which you need to solder the cable cores. If they are copper or brass, then they can be soldered only after pre-treatment with acid, after which they are well fixed. You can purchase special solder, but it will be more expensive.

Then the other ends of the wire must be soldered to the contacts of the screwdriver. To make this process easier, you can use an old non-working battery from this model of screwdriver. First, we need to disassemble the battery and clean the middle, since we only need its body.

When disassembling the battery, be careful because... its contents contain harmful substances. It is best to use hand and respiratory protection.

A soldering iron is needed to convert a cordless screwdriver into a corded one.

After cleaning the case, it is washed, for which a weak alkaline solution is used, which must be completely dry. The ends of the cable must be soldered to the contacts inside the battery case, and do not forget to maintain the polarity.

If you reverse the polarity, the working tool will rotate in the opposite direction, then you will need to get used to this and use reverse in the opposite position. Or you will have to redo all the manipulations to convert a cordless screwdriver into a mains one.

Before soldering the wire to the battery case, you need to make a hole in its lower part and thread the wire into it. In this place it is necessary to secure the wire well so as not to tear it out during work.

After completing the above work, the body can be assembled. Just be sure to add a counterweight inside that matches the weight of the battery. With such tools, the center of gravity is in the handle; if this is disturbed, it will be inconvenient to work. This design increases the load on the hand, but reduces the load on the hand. This will cause you to be very tired, because working with such a tool will be inconvenient.

It is best to use rubber as a counterweight; it will not only act as a counterweight, but also act as additional insulation. You need to cut the rubber a little larger, then it will fit snugly in the body and not dangle during operation.

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Alternative methods

Old inverter welding can be used as a power supply.

You can use a car battery as a battery, but if the voltage is the same, the current strengths will be different. This will lead to rapid overheating of the screwdriver motor. This solution is suitable for short-term work away from the mains. In this case, the cable is connected not to the power supply, but to the terminals of the car battery.

You can make a portable power supply, for which you use a transformer with necessary parameters and a rectifier. It will be difficult to make a transformer yourself without the appropriate skills, but it can be selected from some other equipment, then all that remains is to make a rectifier.

To create a rectifier, you will need to make a diode bridge from semiconductor diodes; its parameters are selected for a specific screwdriver.

A good solution would be to use a power supply from a computer; at its output you can get the required current. The presence of a cooling system makes such a unit reliable and durable. Refinement of this device will consist of creating an insulating housing and grounding.

Old inverter welding can be used as a power supply. True, it does not have the same current strength, so improvements will have to be made. All components are left, only the secondary winding is added, this way you can achieve the required performance. Here you need to have special knowledge in order to calculate everything correctly.

How to convert a cordless screwdriver to 220V? About a year ago I discovered that my Ryobi 18V tool battery had become unusable and since I was working overseas I was unable to get a new one. So I came up with a device to safely run my tools on AC (household current) and stop worrying about my tools stopping functioning on the way to work.

I've enjoyed all the benefits of battery powered power tools... They're convenient, portable, and you can often get a whole range of tools that all run on the same battery. And then the inevitable happened - the diodes on the charger began to blink strangely, and the battery began to discharge almost instantly.

I was faced with two options: drop a few thousand on a new set of batteries or try to rebuild them myself. I didn't like either of these options and I didn't have time to order parts from overseas. As with everything in my situation, for an alternative solution I searched for information on the Internet. I found some guys who connected car batteries to their drill, but I dismissed that idea too. And then I came across the idea of ​​using instead of batteries old block laptop power...

The voltage was correct, but, alas, its power was too low. Even at 180W, the most powerful PC power supplies could not provide enough current to overcome the inrush current of my circular saw or an angle grinder.

The operating principle of the PC power supply suited me, I just needed something more powerful. After a little research, I discovered that the power supply for a laptop is what is called a "switching power supply". It turns out that switching power supplies are very common in the world, they are affordable and come in a variety of voltage and power ratings... I ended up choosing a 350W AC/DC power supply from a reputable company called Meanwell with a range of voltages DC 15-18 volts.

Connecting a power source to a discharged battery is very simple, and in this manual, converting a screwdriver to a mains-powered one with your own hands is described in detail.

Step 1: Warning

Before you begin, please understand that you have a power supply capable of discharging 20 amps. Although the assembly is quite simple, if you are not comfortable working with electronics, then it is better to seek professional help.

The cable coming out of the battery and the DC connector from the power supply are made from a standard 120V AC plug. The plug and cable were chosen due to availability and the ability to use a standard extension cord if necessary.

Under no circumstances will I connect an AC powered device, tool, or other equipment to this power source. If you decide to create this device, think ahead about who might use it. If there is a chance that someone else not trained to use this machine could use it, I would suggest making a different type of connector and cable - something more unique, but capable of carrying current.

Step 2: Tools Required

Materials:

• (1) worn out 18V battery
• (1) 15V 350W AC/DC switching power supply
• (1) IEC C14 electrical outlet (for AC input)
• (1) Standard 120V receptacle for use as DC output or twist-lock generator receptacle
• (1) computer power cable (has a mating connector for a C14 socket)
• (1) 16-18 gauge extension cord (regular plug or twist-lock alternator plug required)
• (1) small tool box (large enough for power supply and battery storage)

Tools:

• small screwdriver
• pliers
• wire cutters
• hot glue gun
• epoxy resin
• soldering iron
• razor blade
• hacksaw blade
• drill
• multimeter

Step 3: Gut the battery

1. Using a screwdriver, remove the 6 screws at the base of the battery
2. Separate the two halves of the case and remove the battery pack.
3. Save (2) yellow square buttons and steel spring.
4. Cut the wires leading from the battery to the terminal block.
5. Save the plastic terminal block and the positive (+) and negative (-) terminal strips.

Step 4: Modify the Wire

Cut off the female end of the power cord (16 gauge). The remaining cord length is up to you.

Remember that this cord will be connected to your power source, but you can always use an extension cord if your instrument will be located far from a power source. I think that a meter or two will be enough.

Lay the wire. There are 2 options

Option A: Drill a hole in the battery cover to match the diameter of the outer sheath of the wire. The location of the hole is your choice. You can place a rubber boot over the wire where it exits the battery pack to relieve the stress of bending it.

Option B: Install the rotary adapter. This adapter will allow you to rotate the cable from the front to the back of the battery pack anywhere at an angle of 180 degrees. This tutorial will use a rotary adapter. If you have access to a 3D printer, you can download the STL files from www.thingiverse.com and print them - search for "18V Battery Swivel Cable Lock".

Cut about 15 cm of outer insulation from the cable, expose and tin about 5 mm of wires.

The rotary adapter consists of (3) parts:

• (2) clamp halves
• (1) swivel base

Make sure the clamp halves can completely surround the outer sheath of the cable. Sand the inside of the clamp halves until they fit snugly against the cable insulation.

Step 5: Cutting the Hole

1. Mark a 1 cm wide section to be cut from the bottom of the battery cover.
2. Using a 3mm drill bit, drill a series of holes along the path, large enough to allow the hacksaw blade to continue cutting.
3. On the inside of the bottom cover along the path where you will cut there will be two posts from the original screws. Cut them off.

Step 6: Working with Epoxy

1. Pass the wire through the groove in the bottom cover.
2. Using superglue, attach the clamp halves to the edge of the outer insulation.
3. Install the swivel adapter onto the clamp halves by passing the stripped wires through the small slot in the swivel adapter.
4. Secure the swivel adapter to the inside of the bottom cap with epoxy resin

Step 7: Turn on the soldering iron

1. Cut about 10 cm from the 20 cm exposed wire.
2. Strip about 5mm of insulation from the wires and solder them to the positive and negative terminal blocks (see the attached image to determine the polarity of the cable if you have the same socket).
3. Reassemble the terminal block and install it into the top half of the battery compartment cover.
4. Use a hot glue gun to fill the cavity where the terminal block is
5. Attach the wires from the top half of the cover to the bottom half of the cover using wire nuts or cable clamps.
6. Assemble the top and bottom halves of the battery cover using 4 of the 6 screws. Don't forget to install the yellow side buttons and springs.

Step 8: Place everything in the case

Now it's time to make a housing for the power supply.

1. Position the power supply in the box so that there is room for the battery adapter, AC input plug, and DC plug.
2. Mark the location of the four M4x6 mounting screws for the power supply to move it into the box. Drill holes in the box to mount the power supply, but do not install it yet.

Step 9: Laying the Connectors

1. Find the location on the box where you want to install the incoming AC outlet and outgoing DC outlet. I prefer to install one on each side and run the wires under the power supply.
2. Solder to the positive, neutral and ground pins (3) 30 cm long 16 gauge cables for electrical outlet IEC C14 supplying alternating current.
3. Solder (2) 12-inch, 16-gauge cables to the positive and negative terminals of a standard AC outlet with outgoing DC power.
4. Make a couple of socket profile templates and transfer their outline to the box. Using a sharp utility knife, cut holes for two sockets.
5. Depending on the type of outlets, attach them using bolts, glue or snaps
6. Apply a little hot glue to the wires on the outlet to protect the exposed terminals.

Step 10: Finishing the Wire Connection

1. Connect the connector pins to the specified power supply pins.
2. Place a plastic protective cover over the power supply terminals.
3. Make sure the power supply selector switch is set to your country's voltage, 120 or 240 VAC.
4. Connect the portable power supply to an AC outlet using a standard computer cable.
5. Plug the battery adapter into a DC outlet.
6. Apply power using the switch.
7. Using a multimeter, check the polarity of the battery terminals and adjust the potentiometer on the power supply to above 18VDC (the small plastic Phillips screw located on the far left of all terminal connectors).
8. Once you're sure everything is working correctly, install the power supply into the box and carefully connect the wires underneath or behind it.
9. Connect the battery adapter to your 18V tool and enjoy using it.

Self-powered screwdrivers from a 12V battery are a very popular tool on production lines and at the household level. Its advantage is considered to be that it is not connected to the electrical outlet; it is very convenient to carry out work on drilling and fastening screws. As a disadvantage, we can note the high cost of rechargeable batteries and their relatively short service life - from 3-5 years, with intensive work it can be even shorter. Therefore, many people think about how to make a power supply for a screwdriver with their own hands. When purchasing and replacing batteries, financial costs can range from 50 to 80% of initial cost new screwdriver. Given their financial capabilities and needs, many consumers are looking for a more economical way to continue using old screwdrivers. One of these ways is to remake its power circuit for a 220V outlet network.

How to convert a cordless screwdriver into a corded one

Let's look at the two most accessible ways to remake a screwdriver with 12V DC power with your own hands quickly and with minimal financial costs:

• Use the original charger of the screwdriver;
• Use the power supply for the screwdriver from the PC system unit.

There are other methods of alteration, but they require more practical skills and knowledge in electrical engineering; these are accessible even to amateurs.

Using a screwdriver charger

This is the simplest and least expensive method, except for the cost of electricity and solder when soldering contacts.

Sequence of actions:

• The screws securing the charger housing are unscrewed and the top cover is removed;
• The conductive wires of the power cord are soldered to the output contacts of the charger. The wires must be flexible, stranded, with a cross-section of at least 2.5-4 mm2 in order to withstand current loads during operation, the cord length is 3-4 m;

• You can solder wires to the output terminals of the charger, to which the contacts of the battery pack are connected when you install it for charging. This method has certain difficulties - the terminals are made of brass alloy, and copper wires cannot be soldered to them with ordinary solder;
• It is necessary to clean the soldering area with a file or sandpaper until the metal appears yellowish;
• Warm up the terminal well with a 40-60 W soldering iron, lubricate it with a special paste (solders for soldering non-ferrous metals are sold in radio parts stores), then the tin solder will reliably adhere to the brass;

• After the soldering points are ready, you can solder tinned copper wire ends to them, with red insulation for +, with blue or black insulation for minus;

This entire procedure can be avoided if you remove the terminals from the board and solder wires to the board in their place. You can remove the power cord from the charger output through the holes in the case where the charging contacts were located, or make an additional hole commensurate with the diameter of the power cord.

Some people are confused by the third contact at the output of the charger; you only need to use two: “+12V” and “-12V”. The polarities of the contacts are indicated on the case or on the board; for reliability, you can plug the charger into a power outlet and use a multimeter to check the presence of 12 V DC voltage at the output and the polarity of the contacts. The remaining contact is for the sensor for automatic control, disconnecting and connecting charging; when the battery reaches its full charge level, the sensor turns off the charger. In our case, this function is not needed; the terminal can be left or cut off from the board. If you are going to use this charger for its intended purpose, then you do not need to remove the terminals; solder the wires from the bottom side of the board to the conductive tracks.

• After soldering the wires, the cord is brought out and the charger case is closed. The opposite end of the cord is stripped, the copper conductors are tinned with solder.

The next stage of work is preparing the input power contacts on the screwdriver itself:

• Remove the battery container from the screwdriver handle;
• Open it and remove the battery cells;

• We drill a hole in the body of the battery container for the power cord;
• We solder the ends of the wire coming from the output of the charger to the contacts in the battery container from the inside, observing the polarities;
• The terminals on the container are also brass alloy, so strip and use brass solder if necessary;
• Secure the wire inside the container to the wall of the case so that it does not come off when pulled. This can be done with a flexible plastic plate, screwing it to the body inside the compartment with two screws. Lay the power cord under the plate, so it will be securely pressed from the inside;

Important! Do not use metal plates as clamps to secure the wire in the charger and on the screwdriver, or use a dielectric spacer (plastic, rubber, cardboard or other insulating material) between the wire and the plate. Otherwise, the metal plate may crush the cord and cut through insulating layer, which will lead to a short circuit.

• The battery container is closed and installed in the screwdriver handle;
• The charger is plugged into the outlet; if everything is done correctly, the screwdriver will function.

It should be noted that if the polarities are reversed, no disaster will occur; the screwdriver chuck will rotate counterclockwise, in the direction of unscrewing. But each product has a reverse switch, so in order not to solder the contacts, just switch the rotation in the other direction. It is recommended to observe polarities in order not to mislead users, and rotation was carried out in the direction in which the arrows near the switch point.

Using a power supply from a PC system unit

This method is used if there is no original charger for the screwdriver, or it is faulty and cannot be restored.

Under consideration pulse block power supply LC 300-ATX P4, the output of which is three types of DC voltage: +3.3V; +5V and +12V. The 12 volt line can withstand loads up to 15A, this is a power of up to 180W. This is no less than what batteries provide, but, as practice shows, it is quite enough to screw screws into dense wood.

Sequence of operations during rework:

• The power supply is removed from the old PC system unit; to do this, you need to disconnect all the buses with connectors going from it to other boards, and unscrew its case;

• The cover of the metal case is opened;
• Connectors with wires are bitten off at a distance of 15-20 cm from the board;

Important! Do not cut the wires going from the board to the fan - there will be no cooling, and the power supply will quickly fail.

• On all power supply models of this series, the colors of the wires are soldered according to the standards, black - body, yellow +12V, orange + 3.3V, red +5V;
• We connect the green wire for turning on the power supply to the case (black wire) through the switch;

• It should be noted that a switching power supply works effectively when all its outputs are under load, so you can solder a light bulb, black and red wires, even a 12 V car one to the +5V output. It will not glow brightly, this is not required, the main thing is that the chain was under load. We do the same with the 3.3V line - solder an orange and black wire to a 5-10V lamp. One of these lamps can be displayed on the front panel as an indicator that the power supply is turned on and power is supplied;

• Using a screwdriver, we run the black wire to the negative in the battery compartment and connect the yellow wire to the positive. Removal of galvanic cans from the battery compartment and soldering of wires is carried out according to the method described earlier;

• The remaining excess wires can be bitten off or, for reliability, run parallel in one line;
• After connecting all the wires, turn on the power supply; if everything is done correctly, the screwdriver will work.

It should be noted that there are other ways to assemble power supplies on a transformer that deliver a full power of 300-400W. In our case, we considered options that did not require capital investment and great knowledge. In other cases, when you make a power supply for an 18V screwdriver with your own hands, a power supply for a 12V screwdriver from a PC will not work. It is possible to increase the voltage to 18 volts with certain modifications, but this requires detailed consideration in a separate article; other options, knowledge of electrical engineering and practical skills will be required.

Video

If you have a screwdriver that is used mainly indoors, the question often arises of how to convert it to mains power. You need to take this seriously. For example, you can take a 12 V tool with a ni-CD battery. This version of the product can be powered from an outlet if it is remade correctly.

Many may not understand why the tool should be transferred to the network. In fact, over time, the battery weakens and sooner or later the power supply must be replaced. As practice has shown, this is expensive, and selecting a high-quality part can take time and money. If you switch the screwdriver to work from the network, you can:

• Give it a second life;
• No longer depend on the charging process;
• Use it without regard to the power of the torque element.

The latter directly depends on the battery charge. If you work from the network, then the power of the device will be at the same level. The only drawback of working from the network is the dependence on the length of the cord. Therefore, in the design presented below, an option with a removable element will be considered.

Materials

Before you begin the task at hand, you need to see if you have everything you need to “upgrade” the tool. In the process you will definitely need:

• Power supply from a computer;
• 12V screwdriver;
• Capacitor;
• Soldering iron;
• Drill;
• Insulating tape;
• Power connector XT60;
• A 6 W bulb or two 3 W bulbs.

These tools and materials will help you convert your screwdriver to mains power without harming the tool. Moreover, the option of organizing a removable cord will be considered further.

How to transfer a screwdriver to the network

Why is it necessary to transfer your home screwdriver to the network? This tool is quite powerful, even with a weak battery. That is, under load it can consume up to 200 W. Batteries generally cope with this without problems, but to operate from a wall outlet, a power supply is required. It is he who will be able to turn an alternating voltage of 220 V into a constant one. Since most power supplies are 12 and 24 V, it is worth converting a 12-volt tool.

If you look at power supplies for screwdrivers on Chinese sites, the price is not much cheaper than a fairly high-quality screwdriver. Therefore, to reduce the cost of the process, it was decided to use an element from a computer, whose power is usually 500 W. Usually, the sticker on the power supply contains information about the power lines, for example 25 A. At 12 V, this parameter is equal to a total of 300 W of power.

• To begin with, be sure to disassemble the screwdriver battery. The batteries need to be removed from it. It is important to preserve the terminals. This is important, since the unit will be made removable so that the tool can be operated both from a battery and from the mains.

In the future, when the batteries are removed, a weight needs to be placed in the housing. This way, your hand will not get tired while using the tool due to imbalance. You can use a piece of rubber or a small wooden plank as a load.

• It is necessary to solder a wire to the terminals, the cross-section of which will be equal to 3 mm 2. In this option, energy will not be dissipated into heat, even if the wire length is 2 m.

As practice has shown, during operation the voltage loss in the wire is quite large. Therefore, the minimum length must be at least 1 m, and the cross-section must be at least 2.5 mm 2.

The capacitor is necessary in order to create an energy buffer for the inrush current, while reducing the load on the power supply. Without this detail, he will go into defense.
The capacitor is soldered. The nut is glued to the glue. Otherwise, it will not be possible to tighten it.

• The next step is to remove the wire from the housing. To do this, it must be fixed so that there is no additional load on the terminals. This can be done by wrapping the wire at the required length with electrical tape. Then everything is put back together.

You can also use heat shrink tubing to secure the wire. It will help secure the element and prevent it from being pulled out in the future when using a screwdriver.

If you follow the instructions, making such an upgrade is quite simple. As practice has shown, it is possible to insert a self-tapping screw into a board or beam without reducing the power of the tool.

Finally, it is worth mentioning that if the power supply is weak, the latter goes into protection. If a capacitor is installed, then most likely there is voltage protection. This problem can be solved by using an additional load on the power line. To do this, you should take black and red wires, to which an additional load is connected, for example, a 6 W light bulb (you can have two 3 W). It will shine and load the line. As a result, the screwdriver will continue to work normally.

On the farm modern man A screwdriver is not a rare tool; this tool is practically an analogue of an electric drill. The advantage of this type is considered to be autonomous power supply from a portable battery embedded in the lower part of the handle. The battery must be periodically charged from the mains through a special charger; after prolonged use, the battery breaks down and requires replacement, and they are not cheap. Therefore, many users are wondering how to convert a cordless screwdriver so that it operates on a 220-volt network.

Sometimes consumers decide that it is necessary to convert a screwdriver into a regular electric drill powered from a power outlet. The question arises how to do this with less time and money. If you have certain knowledge in electrical engineering and practical skills, then powering a screwdriver from a 220V network is not difficult. There are several ways using various devices to convert electricity to the appropriate form for rotating the screwdriver motor.

Ways to remake a cordless screwdriver

Converting a screwdriver to mains power involves converting the voltage to 220V with alternating current at voltage 12 or 18V DC. One of the most reliable and simple ways converting a screwdriver to a network version - use its standard components.

Conversion with standard battery and charger

Converting a cordless screwdriver to a mains one in this case assumes that the circuit is assembled on the basis of a standard charger. The following materials will be required:

• Charger;
• Rechargeable battery;
• 2-3 meters of flexible stranded copper wire, with two conductors, cross section 2.5-4 mm2;
• The usual set of tools and consumables, soldering iron, solder, insulating tape or heat shrink tubing of the appropriate diameter for the wires. To disassemble the screwdriver, you will need a screwdriver, side cutters and a mounting knife for cutting and stripping wires.

The sequence of operations in the process of converting a screwdriver into a network one:

• Remove the cover from the charger body;
• The ends of the wire are soldered to the output contacts of the charger board, which are connected to the battery during charging, observing the polarity. A conductor with red insulation goes to the “+” terminal, with blue insulation – to the minus terminal;

• Polarities can be determined by the inscriptions on the board or product body. To be reliable, you can turn on the charging and use a multimeter to measure the 12 V output and determine the contacts by polarity;
• Galvanic cells are removed from the battery case;

• The charging wire is connected to the contacts inside the battery case, observing the polarity.

Thus, the screwdriver is converted into a network one. When the device is plugged into the outlet, the corresponding voltage of 12 or 18 V DC will be supplied to the input circuit of the screwdriver.

Maintaining polarity is recommended, but not required. When the polarity is changed, the motor shaft will rotate in the opposite direction; all modern screwdrivers have a polarity change switch; in fact, the rotation of the screwdriver chuck is reversed.

Important! The terminals on the charger board are usually made of brass alloy, to copper wires they must be soldered with acid solder or removed altogether, and the wires must be soldered onto the tracks of the printed circuit board.

Before soldering, holes are made in the battery and charger housings through which the wire is pulled. To fix it more rigidly within the body, you can tie it into a knot and wind electrical tape so that the winding diameter exceeds the Ø of the hole.

Replacing a faulty charging board on a power supply from a computer

In the event that the charging board included in the control unit of a screwdriver is faulty, in order to make a network version, a power supply with parameters suitable for voltage and power is installed. Sometimes the power supply comes from personal computer. It must be taken into account that the mains power is converted to 12 volts DC, the screwdriver at idle speed consumes current up to 4A, for a short time at the moment of tightening - more than 40A, then the peak value of power consumption can be up to 480 W.

You can install a power supply from a laptop, they are compact and easy to use, but the maximum power of these models is within 100W, a little more than this is not always enough.

The output voltage is 19V, there are screwdrivers with this power supply.

Power (P) = 19 A x 6.15 A = 117 W, then you can add a 12V converter, and the screwdriver will idle and tighten the bolts with little effort. When screwing screws into a tight wooden surface Such a power supply may not last long - it will burn out.

It is more reliable to use power supplies from system units desktop computers. They are more powerful and in all respects are suitable for connection to screwdrivers.

The peak power of such a power supply is 500W; the rated load for long-term operation is 460W, this is exactly what is needed for a screwdriver with a 12V power supply.

On the top cover of the metal case there is a fan, which is connected through connectors to the board. Ventilation cooling allows the power supply to withstand large peak loads of 500W for several minutes. Sometimes fans are located on the side walls, this depends on the PSU model.

To connect such a power supply to a screwdriver, you only need to perform a few operations:

• Disconnect all power supply connectors from the motherboard and other elements of the system unit;
• Unscrew the fastening screws on the housing of the power supply unit and the system unit, then remove it from the system unit;
• There are no problems connecting to a 220V network; a wire with a connector is included in the power supply kit;
• You will have to look for a 12 volt output; there are even two of them in this power supply model; you can find them by the markings on the printed circuit board. On some connectors it is written output voltage opposite the contacts;

FYI. When there are no inscriptions, you can navigate by the color of the conductors; in this series, the +12V power supply is connected from the board to the connector using wires with yellow insulation. The negative connection is made with black wires.

• To check the correctness of the selected pair, you need to turn on the power supply and measure the voltage with a multimeter;

Pay attention! In our case, we use a pulse power supply, which will not start outside the system unit circuit. Without going into details of the operation of individual semiconductor elements, we will simply accept as an axiom that modification is needed, which consists of a simple jumper.

• The green wire, intended for turning on the power supply according to the standard circuit, must be connected to the black conductor; this is done directly on the board. The excess piece of green wire is bitten off, the remaining end is stripped and soldered onto the board track to the black conductor;

• After the modification has been made, the power supply can be connected to the network and checked with a multimeter for the presence of 12V on the selected pair of wires;
• The yellow and black conductors can be extended and a connector soldered to them;
• In the battery case for connecting a screwdriver, as in previous cases, the galvanic banks that have expired are removed, and the mating part of the connector is installed to the line from the power supply. The options may be different, you can solder the cord to a screwdriver, and connect the connector to the power supply, as you wish;

• When soldering connectors and connections, do not forget to first put heat-shrinkable tubes on the wires and shrink them with a hot air gun, insulating the soldering areas. As a last resort, use regular electrical tape;
• The unused leads of the wires from the power supply can be bitten off or rolled up, the ends insulated and folded inside the case.

Pay attention! When assembling the case, do not forget to connect the fan. If you soldered it or bit it off during installation, you need to remember the connection contacts. The fan is powered from a 12V line, using this feature you can easily find the screwdriver connection points.

Transformer circuit for powering a screwdriver

One of the available ways to quickly power a screwdriver from the mains is to use classic scheme with a step-down transformer for 220V/12-15V and a diode bridge, an AC-DC voltage converter.

All elements are easily placed in any housing; the necessary controls, monitoring and indications are displayed on the front panel.

Transformers and diodes with appropriate parameters that can withstand powers of more than 100 W can be taken from an old household appliances(TVs, tape recorders), from voltage stabilizers and other power supplies. If necessary, we remake the transformer, rewind the secondary winding or install a terminal in the winding with a certain number of turns to achieve 12-15V at the output.

It is recommended to place the diodes on a duralumin radiator, which effectively removes heat, extending the service life. Having certain practical skills and knowledge in electrical engineering, you can wind the transformer with your own hands.

There are many power supplies on sale with suitable characteristics to power a screwdriver from the mains, but this requires financial costs. If you have an old PC system unit, it is not difficult to remake the power supply, especially since, if necessary, it is not difficult to restore it to its original state and use it for its intended purpose.

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