How to choose a power supply for a screwdriver? Tips and tricks

How can you determine which charger is best for your tool if they are tied according to parameters? The most popular are self-powered drills and screwdrivers. Therefore, chargers for this type of tool are most in demand.

When purchasing the tool itself, you receive a known compatible charger. The notorious price/quality ratio also applies to these devices. If you have purchased an economy class power tool, it is foolish to count on an automatic charger equipped with protection, a timer, charge level and temperature control.

Advantages and disadvantages of different batteries

Nickel-cadmium devices are considered one of the most popular today. The power supply for a screwdriver with such a battery is quite cheap, and the charging process is quite fast. Among the disadvantages is the loss of unused capacity on repeated charging.

Chargers for nickel-metal hydride batteries are offered by Hitachi. These batteries are more environmentally friendly, more expensive, but the capacity, and with it the energy density, is much higher. There is virtually no memory loss in these batteries.

Lithium-ion batteries have more interesting characteristics. There is no memory effect here. The energy density is also significantly higher. The price is also slightly higher than the other two types. Among the advantages is the ability to charge at any time, regardless of capacity.

Types of batteries

A charger for a screwdriver is created taking into account the features of an autonomous power source. The following sections discuss popular rechargeable batteries. When studying the compatibility of the functional components of a screwdriver, it is recommended to pay special attention to charge recovery modes.

Nickel-cadmium

Lithium battery charger

These batteries are different:

reasonable cost;
good energy indicators;
long service life.

Unfortunately, big problems arise at the disposal stage. Harmful chemical compounds in Ni-Cd batteries cause great harm to the environment. For this reason, the use of such products is gradually being phased out in many countries.

If other data is not indicated by the manufacturer, select the operating mode along with a suitable electrical circuit diagram for the screwdriver according to the following data:

to extend service life, it is recommended to “train” with 2-6 full work cycles before starting operation and subsequently every 6-8 months;
long-term storage in a discharged state is permissible;
pre-discharge voltage – from 0.9 to 1 V;
the nominal capacity is maintained only at positive temperatures;
overheating is unacceptable during the recovery process (not higher than +40°C);
the completion of the cycle is indicated by a slight decrease in voltage;
The charge current is calculated using the formula:

2*C.

Important! The letter “C” denotes the capacity indicated in the battery passport. If C=2.5 A*h, you can use a charge with a current of 5A = 2*2.5.

Sulfuric acid batteries for screwdrivers

Products in this category are created on the basis of lead cells with an acid-type gel electrolyte. Advantages:

simplicity;
reasonable price;
Possibility of use in any position.

The main disadvantages of sulfuric acid batteries are their significant dimensions and heavy weight. The cells are charged with a voltage of 1.8-2 V while maintaining a current of 0.1-0.15 * C.

Li-ion batteries for screwdriver

This is the most common modern solution. Batteries of a similar design are used in smartphones and laptops, and other household and professional equipment. Pros:

better performance compared to the analogues discussed above in terms of energy storage per unit volume (weight);
wide operating temperature range;
long-term preservation of good operating parameters;
no excessive recycling requirements.

One standard cell is charged with a voltage of 3.6V to a level of 4.2V. Exceeding the threshold set by the manufacturer will shorten the service life. A low level limits savings capabilities. The energy potential of batteries is restored with careful temperature control.

Cordless or cordless screwdriver?

Both corded and battery-powered devices have their pros and cons. Thus, a tool equipped with a battery is highly mobile. You can use a screwdriver at high heights; the absence of a wire prevents the possibility of it getting caught.

Among the disadvantages of the battery solution is the amount of charge. It is necessary to charge the battery periodically.

A powered screwdriver is no longer so mobile, but at the same time it is lighter and has a lower price. There is also no need to purchase chargers and additional batteries.

Often batteries, even from reliable manufacturers, fail. Replacement can cost a significant amount. Therefore, many owners of battery-powered equipment eventually convert it into a network one. A powered screwdriver works no worse from a homemade power supply than from an expensive or, even worse, cheap Chinese battery.

Charging with a faulty battery

Sometimes it happens that the screwdriver itself works, but the battery is broken. There are several options to solve the problem:

Buying new.
Repair of the old one . If you do this yourself, you will need special knowledge. In addition, not everyone wants to work with harmful substances.
Connection via power supply . For example, if a common 14.4 V “Chinese” is available, a car battery will do. You can assemble your own from a 15-17 V transformer. You will need a diode bridge (rectifier) and a thermostat to combat overheating. The remaining components are only for monitoring the voltage at the input and output. No stabilizer needed.
The “native” battery or its substitutes can be completely excluded from the design. The screwdriver will be powered directly from the mains .

Types of chargers

Often, a good screwdriver also includes two types of chargers. These are standard systems and pulsed ones.

With household models, you can use standard chargers that are designed to charge the most ordinary battery. The process of charging the battery to 100% with such power sources takes about 3 hours.

Pulse solutions are used for professional-grade equipment. The power supply for a pulse-type screwdriver can charge the battery in 1 hour using the enhanced operating mode.

Models with different voltages

It’s not enough to decide on the type of charger and the manufacturer’s brand; to purchase, you also need to know the voltage of your screwdriver. The most common options are 12, 14 and 18 V.

12 V chargers

The circuit can consist of transistors up to 4.4 pF. This can be seen in the diagram of the charger for a 12 volt screwdriver. Conductivity in the circuit is 9 microns. Capacitors are needed to control clock frequency spikes. The resistors used are usually field resistors. Tetrode chargers have an additional phase resistor. It protects against electromagnetic vibrations.

12V chargers operate with a resistance of up to 30 ohms. They can often be found on 10 mAh batteries. Among well-known manufacturers, Makita is most often used.

14 V chargers

The diagram shows that for 14 V charging you need five transistors. Other chain features:

The microcircuit is only suitable for four-channel;
capacitors - pulse;
To work with 12 mAh batteries, tetrodes are needed;
two diodes;
conductivity - about 5 microns;
the average resistor capacitance is no more than 6.3 pF.

Devices created according to the circuit can withstand current up to 3.3 A. Triggers are rarely included in the circuit. The exception is Bosch products. In Makita products, triggers are successfully replaced with wave resistors.

18 V chargers

The charger for an 18-volt screwdriver uses only transition-type transistors in the circuit. Other product features include:

three capacitors;
tetrode and diode bridge;
grid trigger;
current conductivity is about 5.4 microns, sometimes chromatic resistors are used to increase it.

The use of high conductivity transceivers is a domestic feature. The current load can reach up to 6 A. Makita often uses high quality dipole transistors in its models.

Whatever screwdriver manufacturer is chosen, the problem of replacing the charger can be easily solved. To do this, it is enough to at least know some of the features of your instrument.

Principle of operation

A typical power source, when plugged into an outlet, does not indicate in any way that it is ready for use. However, the design has green and red LEDs that indicate that the battery is installed. The second indicates that the battery is charging. When the charging process is complete, the green diode will light up again.

As for the length of time with which the power supply for the screwdriver can charge the battery, this depends on several factors. The first factor is battery capacity. Thus, standard models of tools for household use use batteries whose capacity is no more than 1.5 Ah. In the professional equipment group it is higher – 2.5 Ah.

Also, the operating voltage of the battery significantly affects the full charge time. It can range from 2.4 to 36 V.

Homemade charging devices

Damage to industrial chargers occurs quite often. The first reason is unstable voltage in the AC network, the second is battery failure. If the device does not charge the battery, they solve the problem by purchasing a new charger, repairing it, or creating a homemade design.

Circuit with two transistors

The semiconductors used in the product are transistors KT829 and KT361. They can be easily purchased at a radio store or removed from old equipment.

KT361 is used to control the amount of charging current. An LED light bulb is connected to its collector, the brightness of which gradually decreases as the battery capacity increases. When full charge is reached, it goes out. Transistor KT361 also controls the operation of KT829. As the battery capacity increases, the charging current decreases.

Before use, the device is set to the required charging voltage. To do this, a voltmeter is connected to the output terminals of the charger, the device is connected to a 220 V network. The circuit contains a variable resistor with a nominal value of 10 kOhm, which is used to adjust the required voltage at the output of the charger.

To obtain a constant voltage, a transformer with a rectifier unit is used. The minimum required current is 1 A.

Using a custom chip

To reduce memory prices, manufacturers are simplifying circuits. This results in faster battery failure. Using the MAX713 smart chip, they assemble a homemade device for charging 18 or 12 Volt batteries.

The unit is designed for accelerated charging of NiCd and NiMH batteries. The microcircuit controls their condition: when the capacity increases, it automatically reduces the current. The energy consumption of the circuit at rest is imperceptible. The operation of the charger is interrupted at a specified time or by the activation of a temperature sensor.

Visual control of the operation of the unit is carried out using built-in LEDs: HL1 signals the device is connected, HL2 indicates the end of charging.

Connector X1 is used to connect the power source. The power supply current must exceed the maximum charging minimum by 50 mA. The battery is connected to connector X2.

Setting up the charger begins with selecting the charging current, which is regulated by transistor VT1. Its power is calculated using the formula P=(Uin - Ubat)×I.

Legend:

Uin — maximum value of input voltage;
Ubat - battery voltage;
I is the magnitude of the charging current.

Diagram of a charger for a screwdriver.

Calculate the resistance value: R1=(Uin -5)/5; R6=0.25I.

The charging time is selected by switching contacts:

22 minutes - PGM2 is not connected, PGM3 is connected to +U;
90 minutes - PGM3 is connected to pin 16 of the microcircuit;
180 minutes - PGM3 is short-circuited by leg 12;
264 minutes - PGM2 commutes with leg 2, PGM3 with leg 12.

Power supplies for Bosch

The original 18 V power supply for equipment from this manufacturer can also be found in stores.

Prices for the device can vary - from 800 to 2500 rubles. This power source is not suitable for every battery - the charge is switched off if the battery temperature reaches 45 degrees. Power supplies for professional line tools have a starting price of 7.5 thousand rubles.

Top 10 rating according to KP

DeWALT DCD771D2 (average price 9800 rubles)

DeWALT DCD771D2.
Photo: DeWALT Screwdriver from a famous American manufacturer of repair equipment in a signature yellow color. Although the price here is significant, this device can be considered practically a standard. There is a quick-release chuck designed to work with bits or drills with a diameter of up to 13 mm. The electric motor of the device produces 1500 rpm, which allows the screwdriver to develop a maximum torque of 42 Nm. The engine brake instantly stops operation as soon as the trigger is released.

By the way, the kit includes two batteries, which dramatically increases the autonomy of one of the best screwdrivers for the home. However, there are some comments about the model. For example, for some reason the case does not even provide basic additional fastening for bits, and the built-in LED, which is supposed to highlight the work area, does not cope well with this.

Advantages and disadvantages

Excellent workmanship, additional (and not cheap separately) battery included, engine brake

Expensive, there is no mount for bits on the case

Metabo PowerMaxx BS 2014 Basic 2.0Ah (average price 5,700 rubles)

Metabo PowerMaxx BS 2014 Basic 2.0Ah.
Photo: Metabo An extremely popular model from the German company Metabo. The origins of such popular love lie in the fact that the creators managed to maintain a balance of characteristics, quality and cost, which is difficult for competitors to compete with. The screwdriver is very compact, and its weight is only 800 g. For its small size, of course, you have to pay somehow. But not in this case - the electric motor allows the screwdriver to develop a torque of 34 Nm.

If this “baby” is overloaded, then electronic protection will work, which will prevent the device from breaking. Not only that, but the chuck is removable, and hex bits can be used with or without a screwdriver. Finally, it comes with two batteries that charge relatively quickly. The only puzzling thing is the huge case, in which it is easy to lose a small screwdriver.

Advantages and disadvantages

Excellent value for money, weighs only 800g, hex bits can be used without a chuck

For some reason, the manufacturer packages a compact device with a giant case.

Hammer ACD12LE (average price 2700 rubles)

Hammer ACD12LE.
Photo: Hammer A single-speed screwdriver at an affordable price, which is not without compromises. The maximum diameter of bits or drills is 10 mm, but this is not the main problem. But the electric motor, operating at 550 rpm and a maximum torque of 18 Nm, greatly limits the scope of application of the device. In other words, the Hammer ACD12LE is unlikely to cope with anything other than minor household work. But they did not save on reverse, engine brake and operating time. It really reaches 3 hours on a single charge. True, provided that the battery is fresh enough. And, of course, there is only one in the set.

Advantages and disadvantages

Relatively cheap, 3 hours of operation on a single charge

Feels budget, weak electric motor

Makita DF333DWAE (average price 6,000 rubles)

Makita DF333DWAE.
Photo: Makita A well-known model from the Japanese company Makita, beloved by Russians. The reputation of this relatively new screwdriver has been given by numerous predecessors, but it itself is no slouch. Weighing 1.1 kg, the model’s electric motor produces a torque of 30 Nm at 1700 rpm. The keyless chuck is capable of working with bits or drills with a diameter of up to 10 mm. The ergonomics of the screwdriver itself are almost perfect, and the storage case is well thought out. Included are two batteries. By the way, they are assembled from 18650 format batteries, which gives the “Kulibins” huge scope for modifications with their own hands. The model has practically no disadvantages. The only complaints we can make are the lack of mounts on the case for additional bits, and the not very convenient backlight.

Advantages and disadvantages

Lightweight and comfortable to use case, two 18650 batteries, reputation as a reliable tool

The backlight is inconvenient

BOSCH GSR 120-LI (average price 5400 rubles)

BOSCH GSR 120-LI.
Photo: BOSCH Well, what is the rating of the best screwdrivers for the home without products from the German company BOSCH? This model belongs to the “blue” professional line, which means it should be able to do a lot. With a mass of 800 grams, the electric motor of the tool can operate with a torque of 30 Nm, which is good. The batteries are inserted into the handle and do not protrude beyond it, which is also good. As well as the fact that there are two of them in the set.

Quite advanced electronic overload protection is used here, but its operation can be annoying - it does not allow the screwdriver to work at its limit. Of course, this also affects the work in drill mode - the GSR 120-LI cannot drill metal or concrete to the best of its ability. There are also questions about the quality of the instrument. Someone is faced with the fact that the quick-release chuck tries to unwind itself. And someone complains about a burnt-out electric motor after three months of operation. However, the problems are isolated.

Advantages and disadvantages

Weight 800 grams, two batteries and their fastening to a screwdriver

Marriage meets

BISON DSHL-121 (average price 3200 rubles)

BISON DSHL-121.
Photo: ZUBR A Chinese-made Russian screwdriver immediately captivates with its price. For 3,200 rubles in 2021 we get a full-fledged cordless tool. By the way, about batteries. There is only one lithium-ion battery included. But it charges relatively quickly - in 45 minutes. The screwdriver turned out to be quite durable and not afraid of hard work, despite the torque of 25 Nm. In general, it’s a good budget option that you don’t mind using to the limit.

Advantages and disadvantages

Cheap, fast charging

One battery included, the plastic smells unpleasant (but the stench goes away over time)

Hanskonner HCD1838R (average price 8900 rubles)

Hanskonner HCD1838R.
Photo: Hanskonner A powerful screwdriver from a brand with very confusing origins. The official website talks about the experience of Russian craftsmen and German engineers, which does not add clarity. In fact, the pretentious name hides a Chinese manufacturer. The screwdriver is not cheap, but it claims to be a professional tool. This is evidenced by the cartridge diameter of up to 13 mm, the maximum torque of 55 Nm, and two operating speeds. The weight is considerable - the assembled screwdriver weighs 1.7 kg.

There are two batteries included, each with a capacity of 2.4 Ah. By the way, the battery has an indicator of the remaining charge, which is not found in every “Shurik”. Interestingly, the HCD1838R is popular among ice fishing enthusiasts who use a screwdriver as a drill for holes in ice.

Advantages and disadvantages

Relatively affordable price for such power, charging indicator on batteries

Little-known brand, weight under 2 kg

Hitachi DS10DAL (average price 6,200 rubles)

Hitachi DS10DAL.
Photo: Hitachi Another screwdriver from the Land of the Rising Sun. Compact model with an electric motor developing a torque of 36 Nm. The single-clutch quick-release chuck has excellent alignment, which is very useful when drilling. The main feature is fast battery charging. The latter, of which there are two in a set, are made in Japan, which guarantees quality. Perhaps the only things that can upset you are the increased noise and the less-than-optimized ergonomics of the case. But on the handle there is a hook for a belt, which is very useful during construction work.

Advantages and disadvantages

Real Japanese manufacturer, short battery charging time

It's noisy, some people won't like how it feels in their hand

Kolner KCD 12M (average price 1600 rubles)

Kolner KCD 12M.
Photo: Kolner A very cheap cordless screwdriver that can be bought for just over 1,500 rubles. This alone is enough to consider the instrument valid. With the rest, everything is not so rosy. Firstly, the torque of 14 Nm sharply reduces the scope of use of the “Shurik” to small household chores. It is better not to use the KCD 12M as a drill at all. Secondly, the included Ni-Cd battery does not provide very long operation, but it takes as much as 3 hours to charge. There is no smooth speed control either - you pull the trigger and the electric motor starts threshing at maximum. Finally, this screwdriver has very unstable workmanship - some copies fall apart after just a couple of weeks of use.

Advantages and disadvantages

You can’t find a cheaper cordless screwdriver, you don’t mind breaking it

Low power, short operating time

Bort BAB-24X2LI-XDK (average price 9900 rubles)

Bort BAB-24X2LI-XDK.
Photo: Bort BAB-24X2LI-XDK is a battery-powered impact screwdriver, which means it can also be successfully used as a drill. The maximum torque developed by the electric motor is 50 Nm. Although there is a lot of metal in the design, the screwdriver weighs 1.3 kg. There are also two operating speeds. The quick-release chuck is complemented by a spindle lock, which allows you to change drills with one hand. Batteries are controversial here. On the one hand, they hold up well in the cold, but on the other hand, the operating time is not very long. They charge slowly, but there are two of them included. By the way, the case also has a second handle and a limiter.

Advantages and disadvantages

Can replace impact drill, torque 50 Nm

Ambiguous autonomy

Makita

Makita spare parts can also be purchased separately. The manufacturer offers a universal charger for all existing types of batteries. The system will automatically select the required voltage.

On a special control panel you can see the progress of the process. If the battery is not working, this will also be indicated.

Prices for Makita spare parts start at 2,000 rubles (for household models). Chargers and batteries for professional tools will cost much more.

Homemade power supplies

If the battery has become unusable and the charger is broken, then the only way out is to convert the screwdriver from a cordless one to a mains one. So, it is necessary to install some compact power source into the housing of one of the batteries.

The problem here lies in finding the right power supply in terms of size and other parameters. Ideally, all the electronics and the unit itself fit into the battery housing.

The first step is to measure the size of the battery. To do this, it is best to disassemble it, remove the cans, and then measure the internal volume. It may differ significantly from external dimensions.

Charge voltage and form factor

There is no international standardization for the voltage of autonomous power supplies for power tools.

You should understand! Increasing this parameter allows you to reduce the weight and size of the battery. Lithium blocks are assembled from standard cells (1.2V).

For this reason, the resulting voltage will be as follows (for the number of batteries):

10 pcs. – 12V;
11 – 13,2;
12 – 14,4;
13 – 16,6;
14 – 17,8.

Let's find out the electrical parameters

Then you should find out what voltage the tool operates at. The most popular are twelve volt models. A compact power supply for this voltage can be found without much difficulty, but it can be higher, which will significantly complicate the search.

If with voltage everything is more or less simple, then with power it is a little more complicated. Often, manufacturers do not indicate this parameter. But it can be counted. It is necessary to measure the current consumption of the device using a special tester.

Features of choice

As you know, professional screwdrivers are more expensive, but this is no coincidence. They are made with a large margin of safety, for which higher quality and more expensive materials are used. In addition, they have more power, which makes it possible to screw in longer screws and/or work with tougher materials.

The internal gears of the gearbox can be made of plastic or metal. The difference between a professional and household screwdriver will be in the resource

To decide whether you need a household or professional screwdriver, assess the amount of work that will need to be done. If you are starting construction or major renovations, you probably need a professional or semi-professional model. If you need a tool periodically to unscrew/tighten something from time to time, a household tool is more than enough. With such work, the professional tool resource simply will not be in demand. So choosing a screwdriver based on this criterion is not very difficult.

When choosing power, you should take into account not only what power of the screwdriver is indicated in the information from the manufacturer. Due to too much productivity, the device may tighten the screws too tightly, pressing their heads into the surface. As a result, the appearance of the coating deteriorates, and the fasteners, if necessary, are almost impossible to unscrew.

When choosing which voltage is best for a screwdriver, you should take into account that voltage is the main parameter of the device. For example, the motor power of the Makita DDF343SHE screwdriver is 700 W, with a voltage of 14.4 V and a battery capacity of 1300 mAh and a torque of 36 Nm. Whereas the other model Hammer ACD182 has a weaker engine (22 Nm) and a less capacious battery (1200 mAh) - and it seems that this device is about 40% weaker. However, due to the 18 V voltage, the Hummer is able to tighten more fasteners without recharging, even being inferior to its competitor in terms of battery capacity.

You can understand why a screwdriver that seems less productive at first glance is inferior to a more powerful one by doing a little calculation:

the amount of energy stored by the first model is 1.2 x 1.8 = 21.6 Wh;
the second indicator is only 1.3 x 14.4 = 18.72 Wh, i.e. 15.4% less.

When choosing a screwdriver, it is advisable to take into account the presence of a spare battery included with it. Some models even have 2 additional batteries. On the one hand, such equipment will cost more (especially since the cost of the battery is up to 80% of the price of the equipment), but it will be much more convenient to work with it. At the same time, an additional battery is not needed to perform household tasks - the time of work performed with its help rarely exceeds 1–2 hours. While in the process of constant use of a screwdriver (for example, for repair work or furniture assembly), the second battery allows you to not interrupt the work for longer than a few minutes. The discharged battery is charged, and a spare battery is installed in the device.

If there is no need for long-term work, which may require a screwdriver, it is not recommended to buy a model with additional batteries, not only because of its increased cost. It’s just that the service life of such a battery is short, and after a couple of years the user will have to buy a new part without using up even half of the life of the old one.

Tips for finding a power supply

It is much better for a screwdriver if the power source is pulsed rather than transformer type. Pulse devices are smaller and lighter. However, these devices are designed exclusively for uniform current consumption.

If the choice is made in favor of Chinese products, then their parameters and characteristics are often significantly overestimated. You should not trust power supplies that are too light and compact. Soviet models are preferable here. But they have a low efficiency, and therefore they are large in size for good current.

Which drill battery is the best?

Since in this article we provide a rating of cordless screwdrivers, before we begin comparisons and reviews of power tools, we will clarify what types of batteries there are, as well as their positive and negative sides.

Types of batteries:

Nickel-cadmium. Such batteries are large in size, which is not always good from the point of view of compactness of equipment. The advantage of NiCd is its low cost and uninterrupted operation. They are not afraid of temperature changes. They can be charged many times. But the memory effect present here can play a cruel joke, to prevent which such a battery is sent for storage discharged to zero. It needs to be charged only when the battery is completely empty.
Nickel metal hydride. "NiMH" are absolutely environmentally friendly and very light. Another significant advantage is the ability to function for quite a long time without the need to recharge. Such batteries have a memory effect, but not to such an obvious extent as their nickel-cadmium counterpart. Disadvantages: inability to withstand low temperatures. Even at -2, such a battery discharges itself. So storing the tool in an unheated room or in the trunk of a car is not permissible.
Lithium-ion. Li-Ion batteries were developed relatively recently in 1991 by the Japanese corporation Sony. They do not have a memory effect; such batteries have a high capacity and long charge retention. Weigh 40% less than the models described above. Such batteries are often used in the design of professional, reliable screwdrivers.

Powering the device from a laptop battery

A screwdriver connected to an outlet is only suitable for a DIYer. However, a lithium-ion battery from a laptop can be inserted into the tool body. The first step is to disassemble the case. Then the old battery is removed and the wiring is disassembled. The new power source is connected to the instrument. Polarity is very important to consider here. It is necessary to make a special hole on the case and bring the plug into it. This is necessary so that the battery can be charged from the mains.

Cordless drill device

When using a cordless screwdriver, it will be useful to understand how it works.

Any model has:

body;
DC electric motor;
planetary gearbox;
speed mode setting key;
reverse button;
quick-release chuck;
load limiter;
battery.

The electric motor in such a tool is considered a key component. The motor is made according to the standard standard and consists of a winding, an armature and graphite brushes. The voltage to the engine passes through the brushes. The direction of rotation of the motor is directly dependent on the polarity, which changes when the reverse key is pressed.

The presence of a planetary gearbox also cannot be underestimated. This element consists of ring and sun gears, a carrier and satellites. They usually fail when the drill is used, especially if all the gear parts are plastic, as in inexpensive tools.

The speed controller is a wide-pulse controller and switch made on the basis of a field-effect transistor. Control occurs through a variable resistor, while the speed of rotational movements of the cartridge is determined by the force of pressing the button.

Without a battery, of course, even the best screwdriver will not work, since it is the battery that provides constant voltage to the electric motor. With the development of technology, batteries have become more capacious and at the same time small in size. The battery includes several batteries located in one housing.

Operating rules

All those who have already converted their screwdrivers recommend following a few simple rules. So, although the device can now work for a very long time, it is necessary to take short breaks. It is best to fix the power cable at the elbow. The power supply should be constantly cleaned of accumulated dirt. The battery must be grounded. It is undesirable to use a large number of extension cords. All these recommendations will help breathe a second life into your screwdriver, and simple tips will make this tool durable.

So, we found out what power supplies there are for these construction tools.

Benefits of cordless tools

The main advantage of power tools in this category is autonomy. The built-in rechargeable battery ensures the functionality of the equipment without connecting to a stationary power supply of 220 or 380V. This feature is used to carry out repairs in new buildings, in “camping” and other difficult conditions.

Other benefits:

Without the interfering power supply cable, it is easier to carry out individual operations;
Low battery voltage reduces the risk of electric shock;
This tool is much quieter compared to an alternative autonomy solution based on a gasoline generator.

For your information. To be fair, it should be noted that adding a battery adds weight, cost and complexity.