How to find a broken wire in a wall: an overview of methods for detecting and eliminating a break. Do-it-yourself hidden wiring detector, manufacturing diagram and design options Break finder

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During the renovation process, you have to remove partitions, break down walls, or move sockets and switches. It's not an easy job. Electrical cables are laid inside the walls under the plaster, and if done incorrectly, an accident can occur. Even the usual installation of bookshelves is dangerous without first locating the cable locations. Having wiring diagrams, you cannot be sure that they correspond to reality, because the previous owner could independently change the wiring without noting this in the diagram.

That is why it is necessary to determine the location of the cables. Nowadays there are quite a lot of devices on sale for detecting hidden electrical wiring, but sometimes the price is steep. Sometimes it’s better to use ready-made hidden wiring finder diagrams and do everything yourself, getting the device you need on your household.

The simplest indicator

The first option is the simplest indicator of hidden wires. Necessary materials for making it yourself:

We wind the wire onto the magnetic circuit, solder the ends to the cable, insulate it, insert the connector into the microphone input and the hidden wiring finder is made with your own hands in about half an hour. Turn on the maximum volume and move the coil along the search surface. Based on the change in sound, we find the location of the hidden cable.

Single transistor detector

The following scheme was developed by V. Ognev from Perm. The finder uses a feature of a field-effect transistor; it is very sensitive to the slightest interference. When aiming at its gate, the channel resistance changes. This causes a large change in the current flowing through the phone, resulting in a change in sound. The phone must be high-resistance with a resistance of 1600-2200 Ohms, the battery must have a voltage of 1.5 - 4.5 volts, the polarity of its connection does not matter.

When searching for hidden wiring, the device is moved along the wall and the location of the wire is determined by the sound power. Instead of a telephone, you can use an ohmmeter with a built-in power source, then a battery is not needed.

Detector with three transistors

The device for detecting wiring is made on the basis of three transistors, two bipolar KP315B and one field-effect KP103D. A multivibrator is assembled on KP315B, and an electronic switch is assembled on KP103D. The schematic diagram of the hidden wire detector was developed by A. Borisov.

The principle of operation is the same as in the second option, only instead of a telephone a multivibrator with light indication is used. When the detector is turned on and there is no pickup on the antenna probe, the LED does not light up. When radiation appears in the area of the probe, the field-effect transistor closes, thereby triggering the multivibrator and the LED begins to flicker, indicating the presence of electrical wiring.

Parts used in accordance with the diagram, push-button switch – KM-1, power source – any battery or accumulator with a voltage of 6-9 volts.

You can use a plastic soap dish or a school pencil case as the finder body. The blinking frequency of the LED can be adjusted by changing the characteristics of the multivibrator, changing the values of resistances R3, R5 or capacitors C1, C2.

Electrical wiring detector on two digital chips

The hidden wiring finder circuit developed by G. Zhidovkin is very simple.

Composition: 2 digital microcircuits, piezoceramic emitter ZP-3 and 9 V battery. The role of the antenna is played by a piece of copper wire 10-15 cm long and 1-2 mm in diameter.

Induced oscillations from the electromagnetic field of the wiring lead to a change in the output signal of the K561LA7, which is supplied to the input of the K561TL1 with Schmitt triggers. As a result, a characteristic cracking sound is heard, signaling the presence of a cable.

Device based on K561TL1

Unlike the previous version, the wiring finder based on K561TL1, in addition to an audible alarm, has a light indication.

The essence of the work is as follows. When the antenna is brought close to a live wire, an electromotive force with a frequency of 50 Hz is induced in it. This signal goes to the operational amplifier, then to the LED and the input of the K561TL1 microcircuit with a piezoceramic emitter at the output. This causes the audio frequency generator to start and the LED to flicker.

The finder is economical, the maximum current with the indicator on is 6-7 mA.

The antenna is made of one-sided foil fiberglass laminate measuring 55x12 mm. The initial sensitivity is set by variable resistor R2. If installed correctly, the device, developed by S. Stakhov (Kazan), does not require adjustment.

Universal Wiring Detector

You can make a universal hidden wiring indicator with your own hands, provided that you have some skills in drawing up radio circuits.

The finder contains two independent units: a finder for hidden live wiring and a metal detector. This allows you to detect electrical wiring when it is laid in steel sleeves or when there is no voltage in the network. Additionally, the detector searches for and finds old de-energized wiring, fittings, nails and other metal objects.

The detector is based on two operational amplifiers KR140UD1208. The hidden wiring detector unit is practically the same as the previous device, only without an audible warning.

The metal detector unit works as follows.

A high-frequency generator is assembled on the KT315 transistor, which is put into excitation mode using variable resistance R6. The output signal of the generator is rectified by the KD522 diode and puts the comparator assembled on the KR140UD1208OU operational amplifier into a state where the audio signal generator assembled on the K561LE5 digital chip is in standby mode and the LED goes out.

By rotating the variable resistance R6, the operating mode of the KT315 transistor is changed so that it is at the generation threshold. The status is monitored using a light indicator and a sound signal generator. They should switch off. To detect hidden wiring, you need to bring the device to the wall, when the antenna (inductors L1, L2) comes close to the metal, the magnetic field changes, generation is disrupted, the comparator starts up, and the LED lights up. The piezo emitter begins to emit sound with a frequency of 1 KHz.

Small metal detector

The detector is designed to search for hidden wiring, fittings and other metal objects.

The main difference from previous models is that you do not need to wind the inductors yourself. Instead, a relay coil is used. The work of the finder is based on the task of isolating the difference frequency of two generators, when, when approaching a metal object, one search generator (LC) changes its oscillation frequency.

The metal detector includes LC and RC generators, a buffer stage, a mixer, a comparator and an output stage.

The frequencies of the RC and LC generators are selected to be approximately the same, then, after passing through the mixer, the output will already have three frequencies. The third is equal to the difference between the frequencies of the RC and LC circuits.

The low-pass filter subtracts the difference frequency and sends the signal to the comparator, where a square wave of the same frequency is formed.

From the output element, the meander goes through capacitance C5 to the telephone, whose resistance should be approximately 0.1 KOhm. Since the capacitance and active resistance of the telephone form a differentiating RC circuit, an impulse will be formed during the rise and fall of the meander. As a result, a person will hear clicks with a frequency twice the difference.

Detection of hidden wiring will be detected by a change in sound frequency. The coil is taken from the RES 9 relay, and the moving elements are removed.
Since the relay contains 2 coils with different cores, the common terminals of the windings must be connected to capacitance C1, and the core and variable resistance housing must be connected to a common bus.

Double-sided foil getinax or fiberglass is used as a printed circuit board. The finder parts should be placed on one side; the other side does not need to be etched, it must be connected to the common bus of the device.

A battery and an inductor from a relay are attached to the second side.

The board is installed in any non-metallic case where the phone connector is attached. Setting up a metal detector begins with adjusting the frequency of the LC generator by selecting capacitance C1. The frequency should be in the range of 60-90 kHz.

Then we change the capacitance of capacitor C2 until sound appears in the phone. When adjusting the resistance in different directions, the sound should change.

Depending on the setting, the frequency will change and the detector will make a sound as if searching for a radio station. The closer the metal, the louder the sound. The tonality depends on the type of metal.

Non-standard methods

Finally, it’s worth describing a couple of unusual devices for finding hidden wiring, which can be done even by people who have no knowledge of electronics. If the house has a regular compass, then this is a ready-made wiring indicator. Before use, the wiring should be thoroughly loaded, and look for the location of the wire by the deviation of the compass needle.

The second method is more effective; the force of a magnet is also used. A permanent magnet, preferably neodymium, is attached to a piece of thread and slowly drawn along the wall. Where the cable or fittings pass, the magnet will deflect. This happens due to the generation of magnetic current by electric current. This is how basic knowledge of the physics of magnetic phenomena helps.

During apartment renovations, especially in old houses, an electrical wiring diagram is required. Otherwise, when drilling holes or tapping, you can damage hidden wires that are energized.

Important! Regardless of whether you know where the wiring is located, work in the room should be carried out during a power outage.

A metal and hidden wiring detector is used for searching.

Such a device can be purchased at a power tool store. This is essential equipment for repair teams. However, if you are simply renovating your apartment over a period of several years, the cost of purchasing it is irrational. The design of the device is simple. A craftsman who knows how to hold a soldering iron can make a wiring detector with his own hands. In this case, its value will tend to zero.

How to make a wiring detector yourself?

There are two main concepts:

Voltage multiplication principle;
A radio receiver on a microcircuit that detects an electromagnetic field.

Both designs are easy to manufacture and are assembled using accessible components. If you are into electronics, you can pick up radio components in your workshop. Even if you buy them on the radio market, the cost is incomparable with a factory sample.

Determinant of hidden wiring on transistors

Components for manufacturing:

A multistage voltage multiplier will require ultra-sensitive transistors. BC547 has proven itself well. These are silicon miniature bipolar triodes, with an n-p-n structure. They have a fairly high gain with minimal noise;
Low power resistors. 1Mohm, 1kOhm and 220Ohm. For the first, second and third cascade, respectively;
Indicator LED;
Batteries or accumulators;
Frame.

Schematic diagram of the device:

The first stage receives a weak signal from the antenna, shown in the diagram with an arrow. It is an electromagnetic field created by electrical wiring.

Tip: To increase the search efficiency, it is recommended to plug in a low-power electrical appliance that creates interference, for example, a room fan.

A small current appears at the emitter, which is repeatedly amplified by the second stage. The almost finished signal is fed to the base of the third transistor (cascade). After amplification, an electric current sufficient to light up the LED is generated at its emitter. The device is powered by 6 volts.

For ease of operation, the detector should be placed in a thin and long case. Any old driver from a fluorescent lamp will do.

During renovation work, it is quite common to drill and break walls where electrical cables run under the plaster. It is not always possible to use a wiring diagram, but if it is, there may be little benefit from this - you cannot be sure that the previous owners of the premises or builders did not change the location of the wires without making changes to the diagram.

It turns out Wiring detection is an integral part of not only repair work, but also everyday life, because when driving a nail for a new painting, you can easily damage the cable.

Many unfortunate builders do not think about wiring at all when carrying out repair work, thereby violating safety regulations. The consequences of such negligence can be the most dire, so it is advisable to first identify old wiring in order to protect yourself and your loved ones from unjustified risk.

Here are the main reasons for searching for hidden wiring:

And now - consequences of neglecting safety precautions:

short circuit;
improper functioning of the electrical network;
electric shock;
fire.

In the worst case, such carelessness will lead to death.

Finding hidden wiring with your own hands: a review of the most effective methods

The most effective way, of course, is to contact a specialized company - using professional equipment and many years of experience, it will not only find all the wires, but also provide an exact diagram of their route. But such companies are not available in all cities, and such services are quite expensive, so let’s look at how you can independently find an electrical cable in the wall.

Method one. Set the maximum load on the wiring. Next, take a regular compass and, guided by the deviations of the arrow, determine the place where the electrical wire goes.

Method two. You can also mount your own device, consisting of three transistors - one field-effect and two bipolar. The first transistor will be an electric switch, a couple of others will form a multi-vibration installation. Such a homemade device will pick up electromagnetic waves emanating from the wires. If wires are detected, the light on the device will light up, and the device itself will begin to vibrate.

Method three. Another version of a homemade device can be made from a field-effect transistor, batteries and a head unit (telephone, that is). To search for wiring, you need to run the transistor along the wall - if the device makes a sound, it means the cable has been found.

Method four. It is only suitable for major renovations. Note that it is not always effective and is more suitable for rooms with “old” finishes.

Its essence is as follows: it is necessary to remove wallpaper or any other finishing material from the walls. Under it, if you are lucky, you will find a strip that is a different color from the rest of the wall, or represents an unevenness. This is probably where the electrical wiring runs.

Method five. The classic version, which was used before the advent of wiring finders. The radio receiver must be tuned to a frequency of 100 kHz and moved along the surface of the wall. Where the wire runs, the receiver will emit a characteristic noise resembling interference. Since this method was popular among professional electricians, there is no reason to doubt its effectiveness.

Note! During the procedure, pay special attention to sockets and switches - it is near them that cables mainly pass.

Method six. In this case, the electrical wiring is detected using a conventional hearing aid, which makes it possible to perfectly listen to frequencies up to 50 Hz.

Method seven. As an alternative to a radio receiver, you can use a microphone, preferably an electrodynamic coil one. It must be connected to any equipment capable of capturing and reproducing the signal. The search procedure itself is no different from that using a receiver.

Method seven. You can also tie a small magnet to a string and move it near the wall. It is typical that this method is ineffective in panel houses and on ceilings.

Method eight. Don't be upset if none of the methods are successful. You can always resort to reliable technology for searching electrical wiring that demonstrates one hundred percent results. We are now talking about hidden wiring detectors.

Today, wiring finders are sold in all electrical stores. By running such a device along the walls, you can easily identify not only the location of the cables, but also determine the strength of the voltage in them.

Note! Such devices react to both electrical wiring and metal fittings. Therefore, it is recommended to connect a more powerful device to the electrical point to enhance the radiation.

Live electrical wiring produces an electromagnetic field. Devices for its detection are aimed at identifying the sources of this field, and built-in amplifiers make it possible to more accurately determine the location where the wire runs. But in order for the finder to perform its functions, certain rules must be followed when laying cables.

Cables should only be laid parallel to architectural lines.
Horizontal wires should be located at a distance of 1.5 cm from the ceiling slabs.
If the finishing layer is thicker than 1 cm, then the cables should be laid along the shortest route.
If you do not follow these rules during installation, it will be quite difficult to detect the wiring.

Such devices may vary in detection method and design complexity. The price range is quite wide - from 100 to 3000 rubles.

Note! When identifying wires, the finder can provide both light and sound signals.

Below is a classification of detectors by design complexity.

Devices that, in their operating principle, vaguely resemble metal detectors. They are equipped with a special coil that generates a small electromagnetic field. If a foreign electrical or iron object gets into such a field, it will immediately change.
Devices that detect electromagnetic waves emanating from live wires.
A hybrid of previous devices, which is very expensive, therefore it is used mainly by professionals.

According to the type of design, finders are divided into:

screwdrivers;
testers.

The design of testers is much more complex than that of screwdrivers. Modern models are equipped with laser pointers and are capable of detecting not only electrical wiring, but also telephone cables. Moreover, the testers will allow you to detect even underground wiring. The devices are equipped with a screen backlight, a flashlight and fuses that protect against overvoltage.

An indicator screwdriver is a simpler and cheaper device for detecting wiring, but it is effective only in cases where the wires are located at a depth of no more than 2 cm.

This screwdriver can be used in two ways:

non-contact search allows you to determine the location of the wiring;
contact - makes it possible to measure the voltage.

More modern models of screwdrivers are equipped with a display showing voltage data; As for other devices, they use sound signals for notification.

"Woodpecker" - the most popular wiring finder

In Russia, one of the most popular devices for searching electrical wiring is considered to be the “Woodpecker” (officially, then E121). It makes it possible to determine the location of cables under plaster up to 8 cm thick.

Wiring finder "Woodpecker"

The technical features of the Woodpecker are as follows:

operation from voltage up to 380 Volts;
weight – 250 grams;
possibility of contactless search;
the ability to search for wiring, phase cables, broken electrical appliances and breaks;
monitoring the operation of the meter and fuses;
four sensitivity modes.

Let's take a closer look at these modes. Below is indicated distance from the device antenna to the wire for each of them:

1 – 0-1.5 mm;
2 – 10 mm;
3 – 30 mm;
4 – 40 mm.

The set with the Woodpecker device includes a case, batteries and a registration certificate.

Manufacturing a hidden electrical wiring detector

If for one reason or another it is impossible to purchase a finder, you can always make such a device yourself.

Stage one. First you need to select the body of the future device. For example, a plastic box from a fluorescent lamp may be suitable for this.

Stage three. Then you need to install 5-volt batteries, then drill a small hole in the housing and insert an LED lamp there.

Stage five. All that remains is to secure the lid and test the device. It will notify you that hidden electrical wiring has been detected by a lit lamp.

Note! If the wiring was laid in accordance with all requirements, then it will run vertically or horizontally.

Detecting a broken hidden wiring

If one of the hidden cables has been damaged, you can use one of two existing methods to find it.

Method one. First you need to find out which cable is damaged - neutral or phase. Here you will need an indicator screwdriver, with which you need to check all the contacts of the failed electrical point (switch or socket).

In a switch that is turned off, only one of the contacts will be energized, but in a switch that is turned on, both contacts will be energized. Regarding the socket, there will only be one live contact in it in working condition. In a word, if there is definitely a phase, then you can be sure that the neutral wire has broken.

Note! If the wiring is damaged in some inaccessible place, then it is better to seek the help of specialists, since it is unlikely that you will be able to find the damaged area on your own.

Method two. If you have full access to all sections of the wiring, the problem area can be identified with an ordinary tester. Here is an approximate scheme of work.

First, the electricity supply is turned off at the electrical panel.
Then you need to make two notches on the wire insulation, exposing the metal - one near the outlet from the distribution box, the second two meters from the first.
Next, using a tester, you should determine the resistance in this section of the wiring. If it is low, then there are definitely no cliffs there.
The following sections of electrical wiring are checked in the same way until a section without low resistance is found.

conclusions

As a result, I would like to once again note the importance of determining the location of the electrical line before starting repair work. If this is not done, then the consequences of such frivolity can be the most dire, perhaps even fatal. Therefore, you need to use one of the described methods (it is advisable, of course, to look for electrical wiring using a sensor) even when you are just hanging an ordinary picture on the wall.

Everyone uses household electrical appliances, even those who are far from electricity. And when the lights suddenly go out at home, it begins to seem that life has stopped, because you are deprived of your usual living conditions. That is why, in such situations, it is good for each of us to know how to find an electrical wire in the wall, especially since for this it is not at all necessary to resort to the services of an electrician. Even if there is no special device at home to determine the wiring in the wall, there are methods that allow you to do this without any devices.

Most often, you have to resort to independently determining the wiring in the following cases:

When installing light switches or sockets, drilling into a wall or driving a nail, there is no fear of getting an electric shock.
If a short circuit occurs, which is dangerous because it can cause fires, and, therefore, you need to very quickly find where the wiring has broken.
During renovation or redevelopment of an apartment. When demolishing or erecting partitions, as well as when changing the location of the doorway. In this case, it is advisable to know how to find wiring in the wall without a device, this will avoid damage to the electrical cable.
When moving into a purchased apartment. To determine the location of existing electrical communications, if there are no documents with plans for their placement.

Wiring Finder

The simplest such device is an indicator screwdriver. Many people have it at home, and if not, you can borrow it from your neighbors. Although the indicator is very inexpensive, it is very weak. It is impossible to determine the exact location of the wires even if they are successfully detected; the indicator will indicate a dangerous zone of 30 cm. It will not be possible to find a wire that is not energized using an indicator screwdriver.

The E-121 signaling device, popularly nicknamed the “woodpecker,” is used by many electricians. It is so easy to use that even an absolute amateur can handle it. However, this device can determine not only the location of the wires, but also where the break occurred. The depth of its action reaches 7 cm. This is quite enough to detect a break in the core behind the plasterboard sheathing. In terms of price and quality, the “woodpecker” can be called the best domestic device for searching for hidden wiring.

The MS signaling device produced in China has many modifications, but the most popular model is MS-18. A feature of the Chinese wiring detector is its high sensitivity to anything metallic, so it reacts equally to a conductor, nails, and even reinforcement in panel house slabs. But once you get used to it, you can find the difference in signal strength. When choosing any MS alarm model, it is worth considering that they will not respond to a foil cable. These testers are not popular among electricians, but for the home this is a completely acceptable option, especially considering their low price.

Professional electrical wiring search devices

On sale you can find testers GVD-504A, BOSCH DMF 10 zoom, GVT-92, GVD-503, VP-440, produced by European manufacturers. They are usually used by professional electricians to detect what is hidden under the finish and analyze its condition. They differ from their Chinese counterparts in build quality, compact and beautiful design. The principle of their operation is approximately the same, but the cost is quite high, especially if you buy it for one-time use.

Water table of prices of the devices in question

Old-fashioned ways to find wires in the wall

The high price of special devices is one of the reasons why home craftsmen are interested in how to find a wire in the wall without a device and often prefer the old-fashioned methods of solving this problem, which have been proven in practice more than once. Indeed, in earlier times, when wiring was discovered in the wall, they did without instruments, finding electrical networks under plaster and wallpaper using safe methods.

There are several such methods that allow you to find hidden wiring in a wall without special technical means, and each of them can provide a different degree of accuracy.

Visual determination of the location of the routes. This method is suitable for brick and concrete walls covered with wallpaper, which are removed during repairs; this allows you to easily find the groove where the wires are usually laid. Because when chipping, the integrity of the surface is violated, and even after sealing, the place where it was carried out remains noticeable. If the wall is plastered or covered with wallpaper putty, then it is not possible to visually detect the electrical wire in the wall.
Using a radio or receiver. Experts recommend this method to amateurs who are interested in how to determine where the wiring runs in the wall. Moreover, the most ordinary receiver tuned to medium wave frequency will do for this purpose. To the accompaniment of pleasant music, you should walk it along the wall, watching for the appearance of crackles.
A microphone connected to the radio can be an alternative to the receiver. You should work with it as with a radio; the appearance of noise and crackling will indicate the detection of hidden wiring.

It must be remembered that using a radio or microphone you can determine the location of the wiring in the wall with an error of 15–20 cm. Therefore, when using these devices, it is better to make a small indentation to avoid electric shock and such a safety net will not be superfluous.

Let's try some logic

If the wiring was installed by a professional electrician, then all the conductors in the cavity of the enclosing structures were laid parallel to the ceiling or perpendicular to the floor, and all turns were made at right angles.

Scheme for finding hidden wiring in an apartment

Based on this, we can assume the following:

From the socket or switch, the wire rises straight up and further under the ceiling turns towards the distribution box, therefore, you should not drive a nail in this place.
The line is usually drawn 10–15 cm from the ceiling and 10 cm from the baseboards.
You can visualize the cable laying diagram using previously installed electrical points and sketch it on paper.

It must be borne in mind that such a visual representation cannot be called safe. The cable layout must be checked at least using a radio, but preferably with special devices.

Reasons for broken wiring

A break in the wiring can occur at any time, but most often this happens when the electrical conductors are energized. The cause of cable damage may be a poor-quality product, incorrect electrical installation, and much more. In the place where there is damage, the wire constantly heats up and can break if the voltage increases. In addition, cable rupture can occur due to external mechanical impact on it, when driving nails or drilling holes. Network overload also leads to cable breaks.

How to find a broken wire in a wall

If earlier devices could only detect wires or metal objects, then modern electronic devices help in determining the breakage of hidden wiring. For example, using a non-contact hidden wiring indicator, you can find the location of a phase conductor break. The indicator must be moved along the current-carrying wire, and it will signal where it breaks. Typically, when a wire break is detected, the sound signal stops.

If you have an idea of how to find out where the wiring is located in the wall, you can choose the appropriate search option based on your capabilities.

Video about detectors and methods for finding hidden wiring

When carrying out repairs or even when it is necessary to hang a clock or a picture on the wall, the work contractor has to deal with the problem of hidden cables. Of course, when laying wiring in a new house or apartment, it is advisable to draw up a diagram of its location. And such a problem will not arise in the future. However, if the repair was not major or the layout of the cables in the walls has long been lost, it is advisable to check the drilling location using a special device - a “finder”. “Finder” will help you check the drilling location

Classification of devices

There are three main types of hidden cable detectors:

electrostatic, one of the simplest devices;
electromagnetic, which do not react to all wires, but only to cables with a connected load;
metal detectors that detect the presence of metal parts.

Another frequently encountered option is a combined wiring finder, which uses several methods for searching at once. Each type of these devices has its own advantages and disadvantages. And, if you have experience and desire, all of them can be made on your own.

Electrostatic finders

Devices of this type allow you to detect the electromagnetic field from live wiring. The design of these finders is the simplest. And the features of working with them include:

the need for current in the wires. If the power is turned off, the cables cannot be detected;
When working with the detector, you should first set the appropriate sensitivity. Otherwise, you may not detect wiring that is too deep or, conversely, constantly react to false alarms;
Searching for wires in damp walls or inside structures with built-in fittings most often does not lead to a positive result.

The popularity of the devices is due to their low cost and acceptable efficiency. The list of devices of this type frequently purchased by consumers includes the well-known model Woodpecker E121, and a number of other inexpensive devices. However, you can also make them yourself - it will be even cheaper than buying a ready-made device, and will not take too much time.

Electromagnetic devices

Signaling devices of this type allow you to locate wiring based on the electromagnetic radiation emanating from it. Like electrostatic equipment, they detect hidden cables only when energized. Moreover, for guaranteed detection it is required that some kind of electrical appliance with a power of at least 1000 W be connected to this line - which cannot be done if the hidden wire is not connected to the outlet.

Metal detectors

Metal detectors can be called one of the most effective detectors. With their help, you can detect wires even when the voltage is turned off. However, they also have a certain drawback - along with searching for metal cables, the devices also react to other metal that may be inside the wall, floor or ceiling. And by reducing the sensitivity of the equipment, you may simply not notice a sufficiently buried cable.

The principle of operation of the equipment is based on the creation of an electromagnetic field that causes disturbances inside the metal wire. The detector reacts to most metals and can be used to search not only wiring, but also other hidden parts - from screws and bolts to fittings. The cost of such a device is higher, and it is more difficult to make it at home.

Combination devices

Combined type equipment combines several (usually two) types of detectors. This significantly increases the efficiency of the search, making it possible to guarantee that there will definitely not be a single hidden cable at the drilling site. One of these devices is the TS-75 finder, the circuit of which combines a metal detector and an electrostatic version.

Equipment price

The cost of wiring detectors varies depending on models, brands and functionality. In addition, the amount that will be spent on purchasing such a finder depends on the purpose of the device, which can be domestic or industrial. It is also worth considering the country in which the device was released.

Chinese-made devices (especially of a little-known brand) will cost less - but will not necessarily serve their owner for at least several years. And European models with similar characteristics can be purchased at 3-4 times more expensive - but their sensitivity will be higher and their service life will be much longer.

You should know: Some homemade detectors may be more effective than budget factory models.

DIY finder

For home use, a do-it-yourself hidden wiring finder is usually sufficient, the circuits of which can be called budget. And, although high accuracy cannot be achieved using such a device, its capabilities are sufficient to search for most cables inside walls and other structures. As a result, the owner of this device will receive certain savings on the purchase of an expensive detector, and will prevent damage to the electrical wire during repair work.

To assemble the easiest finder to make, you will need to prepare:

a microcircuit that is sufficiently sensitive to electromagnetic or electrostatic radiation. For example, you can take the K561LA7 model, the purchase of which will not cause much damage to your budget;
a piece of copper wire from 5 to 15 cm long, which will be used as a detector antenna. The best option for such a finder is an 8-centimeter segment;

a piezoelectric element that can be used to determine when the detector has detected electromagnetic waves. As this device, you can use a milliammeter from old tape recorders or an element from an electronic watch.

The last part to start assembly is the power supply. Due to the fact that the circuit requires 9V voltage, a “Krona” type element is selected as a battery. Although you can use 6 AA batteries for the same purpose.

Assembly of the structure

The device can be assembled using a printed circuit board or surface mounting. The second option is used more often and consists of doing the following:

1. Place the microcircuit on a sheet of thick cardboard, in which you need to make 14 holes for its legs;

2. Fix the structure by inserting the legs into the holes and solder all the structural elements;

3. Find a suitable housing in which the circuit will be placed, install it inside, leaving space on one side for the sound source;

4. Install a switch in the circuit, thanks to which the device can be turned on and off without removing the battery.

A properly assembled device can detect hidden wiring quite effectively. When brought to the walls, inside of which there are hidden cables, the hand-assembled device makes a slight cracking noise.

Other search methods

You can find wires hidden in enclosing structures without assembling the detector, which may require some experience in the manufacture of radio devices. To do this, use the following methods:

visual identification of wires (tearing off wallpaper);
using a radio receiver to search. The device is tuned to a frequency of 100 kHz, after which it is carried out near the wall. Where the hidden wire is laid, the receiver begins to make noise;

identifying cables using sockets located on the walls. As a rule, wires run from electrical points in a straight line to the nearest corner.

Another scheme involves connecting a reel-to-reel electromagnetic microphone to a computer or tape recorder. The device may make a buzzing sound where the cable is laid. And owners of smartphones with Android OS have one more additional way - download the special Metal Sniffer program and try to use the phone as a metal detector. The operating principle of such a smartphone detector is based on the presence of a built-in compass for navigation in most models.

Summarizing

Having a hidden cable detector in your apartment or house will increase the safety of repairs. And, if it is not possible to purchase an expensive finder, it can be replaced by a home-made device. Although its efficiency will be lower, and it will most likely not be possible to find the cable inside a reinforced concrete wall.