Modern indicator screwdrivers will relieve the headache of a person trying to figure out how to determine the phase, zero, ground. Difficulties noted below. For testing, a signal generated by a screwdriver is used. Of course, there are batteries inside. The old Soviet indicator screwdriver based on a single gas-discharge light bulb is unusable. Allows you to accurately determine the phase. Therefore, the other circuit is zero or ground.

Correctly determine the phase

Three-core wires

Let's start with terms. The Russian language is deprived of the word zero. But it was used in everyday life due to easy pronunciation. Zero is a distorted zero that goes back to the Latin language. The programmer knows: the term NULL is used to mean empty, undefined variables (devoid of a type). Sometimes the type of data is convenient for compiling algorithms (when passing function values).

Now let's try to find the phase. A typical indicator screwdriver is formed by a steel probe, followed by a high-resistance resistance (for example, carbon), which limits the current, a small gas discharge lamp acts as a light source. Little things, but those who do not know the term contact button, are powerless to define zero. At the end of the indicator screwdriver handle there is a metal platform. This is a contact button that you bother to touch with your finger. Otherwise, the light bulb will refuse to glow when touching the phase.

Let's explain what's going on. The human body is endowed with capacity. Not so great, enough to pass a meager current. The phase begins to oscillate, the electrons go to the network and back. A small current is generated. The size is severely limited by the resistor, it is not easy to kill yourself by holding the contact pad of the indicator screwdriver with your hand, and the other by the water supply pipe. It is impossible to detect the ground directly with the instrument.

Phase detection is fundamental, no voltage should be applied to the chandelier socket when the switch is off. Otherwise, the usual process of changing a light bulb can become dangerous, the last. According to the regulations, the socket phase is on the left. If the switches are set as usual (turned on by pressing up), the methods for determining the phase degenerate by the ability to find the left hand, to understand where the bottom is:

Determining the position of the phase by the color of the insulation of the wire cores

The zero working wire is provided with blue insulation, the earth is yellow-green. Accordingly, the red (brown) color falls on the phase. The rule can be grossly violated. Houses of old buildings were often equipped with wires of two cores. The color of the insulation is in each case white. Individual devices, such as light or motion sensors, have a different layout. For example, the neutral wire is black. Here, get ready to look at the instruction manual, there are countless layout options.

Find a neutral wire in the apartment

According to the rules, the body of the access shield is grounded. It is carried out using a solid-sized terminal, tightened with a powerful bolt in old-built houses, it is easier for residents of modern buildings to navigate the number of cores. The zero bus has the largest number of connections, the phases are divided into apartments (good electricians hang stickers A, B, C; evil ones do not hang them). We can easily trace the layout of circuit breakers, counters.

230 volt UK plug

In each case, the common wire will be zero. Color does not play a decisive role. Although according to the norms, modern cables are equipped with painted insulation. Please note - if the house is equipped with grounding, at least 5 lived at the entrance. The body of the shield is planted on yellow-green. The neutral wire will serve to drain the operating current from the devices (closes the circuit). Merging branches on the consumer side is not allowed. Here are three rules that help you figure out the access shield (note, according to the rules, the tenant should not show his nose there at all - they warned):

• The circuit breaker breaks the phase. There are two-pole models, they are used relatively rarely for rooms with special danger (bathroom). Therefore, by the position of the wire, it will be possible to say: this is a phase. Then it’s worth turning off the machine, ringing the vein on the side of the apartment. Definitely gives the position of the phase.
• The voltage between the neutral wire, any phase is 230 volts. Based on the key feature, we select a vein that gives the indicated difference to another. The spread between the phases is 400 volts. Percentage values ​​are 10 higher, Russian chains are trying to meet European standards.
• With current clamps, we measure the values ​​​​on the conductors. For each phase, a value will appear, the sum of which (by three) must flow back into the network through zero (or a suitable phase). Grounding is rarely used, the current here is close to zero with a uniform loading of the branches. The place where the value is the most is traditionally the null conductor.
• The ground terminal of the switchboard is visible. The sign will help to find the neutral wire in houses with NT-C-S. In other cases, grounding is supplied here.

Additional information about finding the ground, phase, neutral wire

We remind you that cases were considered when there is no indicator screwdriver at hand, but there are current clamps, a multimeter. Then, before entering the apartment, they find the ground, phase, neutral wire, the home network is called. There are three cores, the technique lies on the surface: between the phase and the other wire, the potential difference will be 230 volts. Please note that the technique is not suitable in other cases. For example, the voltage difference between two identical phase cores is round zero. It is difficult to measure and determine with a tester.

Let's add another way - the industry is prohibited. Bulb in a socket with two bare wires. Using a tool, they find a phase, it is possible to close the core to ground. Do not use water, gas, sewer pipes, other engineering structures. According to the rules, the braid of the cable antenna is equipped with grounding (grounding). Relative to it, it is permissible for a tester (a light bulb in a cartridge prohibited by standards) to find a phase.

For determined people, we recommend fire escapes, steel tires for lightning rods. It is necessary to clean the metal to a shine, call the phase site. Please note that not all fire escapes are grounded (although they must be), lightning rod tires are 100%. If you find such a flagrant arbitrariness, contact the governing organizations, if there is no reaction, inform the state authorities. Indicate violation of the rules of protective zeroing of buildings.

Modern screwdriver-indicators for determining the phase, neutral wire, earth

When it is impossible to understand what color the wires are, it is useful to use an indicator screwdriver. The instruction of the curiosity on batteries says: it will be possible to find the ground with the help of a probe. We hasten to disappoint readers - any long conductor is defined falsely. A phase broken in the area of ​​traffic jams, a neutral wire, a real earth - there is only one answer. Not every indicator screwdriver is able to perform the functions equally effectively. The meaning of the operation is as follows:

Screwdriver indicator

• An active indicator screwdriver is able to detect a long conductor by emitting a signal there, catching a response.
• In practice, if the quality of the contacts is poor, the wave quickly decays. An indicator screwdriver shows the presence of earth on an open phase plug.
• To determine the ground, there is a condition - you need to touch the contact pad with your finger. This is the difference between active and passive indicator screwdrivers. In the first one, it is possible to find the phase according to this principle, in the second, the correct determination occurs if there is no contact with this area.

A modern screwdriver-indicator at a distance will allow you to judge whether current flows through the wire. There is a special remote mode. Usually even two: increased and decreased sensitivity. Allows you to weed out the unused part of the wiring. Suppose there are known cases: builders brought two phases into the house instead of one, they confused them in places. Wiring must be used with great care.

I would like to note that in practice it is not easy to measure the resistance of the wiring. It is much more convenient to determine the presence of a phase. There is no danger of burning the Chinese tester (it happens at times when trying to measure the resistance of a live conductor). You should also be aware that low-resistance circuits are determined with an error. For example, most testers with a direct circuit of the probes do not give a zero scale. But if you can’t determine the ground using an active indicator screwdriver, bad contacts are easy. If, when the plugs are turned off, the light burns with a finger pressed to the contact pad, it's time to think about buying a new junction box machine, replace the twists with modern caps.

1. Red - phase.
2. Blue - neutral wire.
3. Yellow is earth.

Usually water-soluble paint is washed off with difficulty. Colors electrical wires it is permissible to put down the colors of printers. The above system is not alone, often occurs. On sale we will find black color. You can use it however you like. Wire marking is done once and for all. It is easier to wash off the marking with concentrated acetic acid, the substance will be needed by those who intend to clean their hands (it is not always easy in practice). Finally, try not to stain your clothes.

Whether it is the installation of a switch or something else, there is always a need to determine the neutral and phase wires.

To be honest, this is a fairly easy procedure, but only on condition that you have the necessary skills in working with electricity. The article will discuss how to deal with such issues.

Introductory part about the principles of operation of electrical appliances

We all know that almost all household electrical appliances require relatively little power - only 220 volts. And in order to bring the electrician to the plug, you need two wires (in some cases, three). So here they are:

1. Phase.
2. Null.
3. Grounding (if insulation failure occurs, it will prevent electric shock). And why, you ask, does a simple layman know where the phase is, and where is zero?

First of all, this is useful when replacing the switch with your own hands, if it should be installed specifically on the phase wire. Who does not know, this will allow you to repair the lighting fixture without turning off the electricity in the whole house.

But not only them, but also household appliances that work with running water or have iron cases. And to connect them, you need to use not only zero and phase, but also grounding.

There are three ways to determine phase and zero. Let's consider in detail all their advantages and disadvantages.

We determine the phase and zero with a phase indicator

In this case, you will need a special probe, or as it is also called, an indicator. In general, this is an ordinary flat screwdriver with a plastic handle, where a visual sensor is placed - a neon or semiconductor lamp.

The procedure for determining the phase is thus simple. It is only necessary to touch the end of the tool to the desired wire or plug it into the outlet. If voltage is present there, then the screwdriver will light up with a faint light.

It is worth noting that this is possible with the correct use of a screwdriver: the finger of the palm in which the tool is located should be pressed against the metal part of the screwdriver. This will close the loop between the ground and the wiring, but you should not be afraid of this, since the same metal part of the device significantly reduces the voltage.

Advantages: simplicity and accessibility of the method, a screwdriver can be bought at any store.

Flaws: risk of injury electric shock albeit mostly on a psychological level.

Video for determining the phase and zero with an indicator screwdriver

We determine the phase and zero with a tester

It uses a more modern device - a phase tester. It will allow the owner to qualitatively measure the strength of a variable or constant voltage. A special rotary switch is used to set the device.

There are also two probes, the first of which must be inserted into the outlet, and the second must be firmly clamped in the palm of your hand. If we get to the neutral wiring, then the display will show a slight voltage or a few zeros. And if on the phase - then the voltage will be significantly higher.

Advantages: modern device, widely available in the domestic market; higher measurement accuracy.

Flaws: there are no significant ones.

Video for determining the phase with a multimeter

We determine the phase and zero by marking

This is perhaps the most unreliable way. Its essence is as follows: today, all the wiring of modern houses has a special color marking, depending on the purpose of a particular wire.

For example, a brown or black wire is often connected to the phase, and the one to zero should have blue tones. Regarding the ground wire, it is made in two colors - green and yellow.

It’s a pity, of course, but in our country, often the negligence of electricians leads to the fact that the rules are ignored and thereby entail the most unpredictable consequences. Therefore, in no case do not rely on the conscientiousness and professionalism of the workers installing electrical wiring in your house.

When the phase wire is determined, we bend it and begin to determine the zero one. They are attached to the shield inside the apartment in such a way that the grounding system as such is excluded. And if you have access to the shield, then you should inquire about the color of the wire that passes by the machines and identify it.

And if, due to the fact that you want to insure or direct access to the shield is not possible, then at any time you can use the good old tool - a cartridge with a light bulb to which the wires are connected. And if you connect one of them or simply touch it to the phase wire, and close the second wire to the remaining two in turn, then you can also determine the categories you need. If there is a contact with zero, then the light will light up, and if with a ground wire, then nothing will happen.

And, as if opposing this method to a more advanced one, we can use the device we have already described - a phase meter.

In this case, the difference in voltage (in other words, potentials) between all wires and already defined phases should be measured in turn. In this case, the phase-zero category must significantly exceed all other categories (earth-phase).

Advantages: relative simplicity.

Flaws: insecurity.

So, together we figured out how to determine the phase and zero.

Installation of internal wiring, self-installation of switches and sockets is often associated with the need to determine the phase and neutral wires. This process is not complicated if you have an idea about the possible ways and rules for safe work with electricity. We have devoted today's article to the solution of these issues.

First, let's remember a little theory. Everyone knows that for the operation of household electrical appliances, very little is needed - the presence of a voltage of 220 volts in the mains. To supply electricity directly to two (in modern homes - three) wires are used. The first of them is phase, the second is zero and the third is grounding, which protects the user from electric shock in the event of a malfunction in the insulation of the device. Why would an ordinary resident of a high-rise building or country house it is necessary to be able to determine zero and phase?

This knowledge may be needed, for example, when replacing a switch on your own, which is recommended to be installed on a phase wire. This makes it possible to carry out repairs to the lighting fixture without turning off the electricity in the entire apartment. In addition, installation of a socket for connecting various household appliances, especially those whose work is associated with the use of running water, as well as those with metal cases. To connect them, in addition to the traditional phase and zero, it is also necessary to use a third wire - grounding.

Phase search by indicator

These days, there are several ways to determine the phase without the involvement of a professional electrician. The first of them involves the use of the so-called probe, or phase indicator. It is a narrow flat screwdriver with a plastic handle, which contains a light signaling device - a semiconductor or neon light bulb.

The technology for determining the phase with this device is simple. It is enough just to touch the tip of a screwdriver to the bare wire under study or immerse it in one of the plug holes of the socket.

If there is voltage on the wire or in the socket, the phase screwdriver signaling device will respond with a slight glow. But this will happen only with the correct use of the device - one of the fingers of the hand in which you hold the device must be pressed against the metal end of the handle. In this case, you close the circuit between the wire and the ground, but you should not be afraid of this, since the voltage drops sharply with a screwdriver and will not bring any harm to the user.

Phase detection by tester

The second option for determining the phase wire involves the use of a more advanced device - a tester or multimeter. It allows you to measure various electrical quantities of direct or alternating current. Using the rotary switch, set the device to measure the potential difference of the alternating current. Hold one of the probes of the device firmly in your hand, and with the second touch the wire under test or deepen it into the hole in the socket. In case of contact with the neutral wire, the multimeter display will show a set of zeros or small voltage usually not exceeding two volts. When in contact with the phase conductor, the numbers on the instrument display will be higher.

There is a third option, which can be attributed to the most unreliable. The fact is that at present, according to the rules for installing intra-house and industrial electrical networks, all wires have a certain color marking, depending on their purpose. So, a black or brown conductor should be used to connect to the phase, blue or blue to zero, and the grounding conductor should be painted partly yellow and partly green.

Unfortunately, the peculiarities of our country and many irresponsible electricians often lead to ignoring the established rules, which can lead to unpleasant consequences. You should not completely rely on the professionalism and skill of the workers involved in the installation of electrical networks in your home. It is better to use the above methods. In addition, until 2011, the wire marking was different from the current one. So, a wire painted black was used for grounding.

Having determined the phase wire, and gently bending it, we proceed to the definition of the neutral wire and the ground wire. The peculiarity of connecting them to the in-house shield does not imply the input of a grounding conductor directly into the housing of the input device. In the event that you have access to the shield, you can specify the color of the conductor passing by the machines installed in it and determine its color.

In the event that access to the shield is not possible or, if you wish, to play it safe, you can use the simplest device that any electrician always has - a light bulb with a cartridge and wires attached to it. By connecting or simply touching one of the wires extending from the bulb to the phase wire, short the second wire in turn to the two remaining wires intended for determination. Upon contact with zero, the light should light up. Contact with a ground wire usually has no such effect.

As opposed to the simplest device, you can use the multimeter already described. Alternately measure the potential difference (voltage) between the known phase and the rest of the wires. The value of the zero-phase pair should significantly exceed the value of the phase-to-ground pair.

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The digital multimeter is very useful thing at home. Using a tester, it is easy to determine which of the wires is phase, zero, and which is ground.

Any electrical network, both domestic and industrial, can be direct current or with a variable. With a constant supply of electrical voltage, the electrons move in one direction, with a variable supply, this direction constantly changes.

The variable network, in turn, consists of two parts - the working and empty phases. The working voltage, which is called “phase” in electricity, is supplied with a working voltage, but the empty one, which is called “zero”, is not. It is needed to create a closed network for operation and connection of electrical appliances, as well as for grounding the network.

Rules for using the multimeter

To determine the phase and zero using a multimeter, it is necessary to clean the ends of the cores from insulation, separate them into different sides to avoid contact that would provoke short circuit, and then apply electricity.

Set the measuring limit on the multimeter AC voltage above 220 V. Insert a voltage probe into the socket marked "V". Touch it to the cleaned core and follow the display. If the value is up to 20V - this is a phase wire, if there is no reading at all - this is zero.

For the correct use of the multimeter, the following rules must be observed:

• It is contraindicated to use the device in high humidity.
• Failed measuring probes must not be used.
• It is forbidden to measure parameters with a value exceeding the upper limit of the measuring instrument.
• During the measurement procedure, do not turn the switch and change the limits.

How a multimeter will help find the phase

In order for the multimeter to show which of the wires the phase is in, you need to set the mode on the device to determine the AC voltage, which is designated as V~, setting the measurement limit from 500 to 800 V. The probe is connected as standard, black to the “COM” connector, red at VMA.

How the multimeter shows zero

After the wire with the phase has been determined, it is easiest to find the zero one. By setting the red probe to the phase, touch other conductors, after which the tester should show a value of about 220 V. From this it will be clear that the second wire is either zero protective or zero working.

It is very difficult to determine with a multimeter where the zero protective wire is and where the zero worker is, since they duplicate each other. It is best to disconnect from the ground bus in electrical panel input wire, then in the tested room between the phase and the ground wires there will be no 220 V, as when checking the phase and zero.

We determine the device ground

The presence of a grounding contact does not mean that this contact is actually grounded. Quite often, this wire is not connected anywhere, but only creates visibility for the user. Competent electricians for the earth choose a wire with a strip, but if the master was inexperienced or neglected this task, then they might not remember the color marking. In such situations, voltage is best measured by touching water or heating pipes. On a wire with grounding, the voltage level will be less than on zero.

Other verification options

In addition to the listed methods for checking the phase and zero with a multimeter, there is a check using a control lama.
The method is quite unusual and requires special care, but effective.

Such a device requires a cartridge, a lamp, a wire with insulation cut off at the ends. When using a lamp, it will be possible to determine whether there is a phase or not, and which phase conductor cannot be established. If during the connection of the wiring of the test lamp to the conductors to be determined, it lights up, then one of the wires is phase, and the second is most likely zero. If it does not light up, then there is no phase, either phase or zero, which is also possible.

A screwdriver with an indicator to help us

The design of the tool is simple. A light bulb is built in. Sting on one end, shunt contact on the other.

The essence of checking with a control screwdriver is to perform the following actions:

• Turn off the power supply from the shield.
• Remove the insulation from the cores that need to be checked for 1 cm.
• We separate them in different directions to avoid contact.
• Apply voltage by turning on the introductory machine.
• Bring the tip of the screwdriver to the bare wiring.
• If the indicator window lights up during this action, then this is a phase, if it is absent, then it is zero.
• Mark the desired core, turn off the automatic box and connect the switching device.

When working with a probe, everyone must follow the safety rules, which consist in the fact that when taking a measurement, you must not touch the screwdriver at the bottom. The tool must be kept clean. Before determining the absence of voltage (as opposed to its presence) in the outlet, you can check the device for serviceability using other electrical equipment that is energized.

By wire color

The simplest and in a reliable way determining the phase and zero is by the color of the wires.
But only if you are sure that the wiring is connected in accordance with all the rules!
Basically, she always lived with a phase of black, brown, white or gray, and zero is blue or blue. May also be lived Green colour or yellow-green, this indicates the presence of a conductor with grounding.
In this case, you can do without measuring instruments, according to the color, it is clear where the phase is, and where is zero.

When installing electrical wiring, the biggest threat is phase conductors. To prevent a situation that entails a fatal outcome, they are painted in flashy bright colors. This is done so that, under certain circumstances, an electrician from several wires can quickly select the most dangerous and treat them with care.

Many of us have never encountered the search for a phase, others do it all the time, and still others need it from time to time. What for? There are all sorts of situations. Here are at least some of them:

1. It is necessary to hang a chandelier with two, three or more shades.
2. You bought an electrical appliance that requires polarity, and our sockets are not designed for this (and this happens, although rarely).
3. You are repairing wiring in an apartment or doing wiring in a house, and your wires are still Soviet, all of the same color. You don’t seem to need much - just learn how to find the phase and zero with the indicator screwdriver that you have.
4. You need to find a bare wire, which is a source of danger (this situation occurs when dismantling buildings, repairing in unfamiliar premises, and it is not possible to disable all this).

But before we start our search, let's figure out what we are looking for.

We all know from the school physics course that alternating current flows in our electrical networks. Some even know how variable it is - 50Hz. That is, in one second, charge carriers twitch back and forth fifty times. The graph of voltage and current in the network graphically looks like a sinusoid.

The amplitude of the voltage fluctuation is about 310 V. If we pass this current through and rectify, then we will get the effective voltage in the network - 220 V. In fact, this is the average value over the entire sinusoid, it is obtained by dividing the amplitude by Square root from a deuce.

And here's where it gets more interesting. Few of the inhabitants know that in Russia there is a three-phase power supply. Visually, it looks like this: not one power wire, but three, and one more, called neutral or zero, come out of the transformer box in your microdistrict. The difference between the first three is that the current and voltage sinusoids in them are shifted relative to each other by 2π/3. This means that if in one wire the cycle is one third, then the second has just begun, and the third has not yet caught up. It is hard to imagine? You can take a picture like this:

This phenomenon is called phase shift.

One such wire and a neutral are connected to each apartment, connecting you to the ends of all three windings of your yard transformer and to the ground. However, you should also have a separate ground in order to divert static from the housings of household appliances.

From this figure, you can understand that the statement "there is no voltage at zero" is not entirely true. It will not be there when everyone in the apartments will have electrical appliances operating from three phases - then the load on them will be symmetrical. But few people would think of putting electric motors from industrial units in an apartment, and symmetrical load happens rarely. Therefore, there is always some voltage in the neutral wire.

Phase search

At present, we can easily determine the phase wire using special devices. This simple operation is within the power of any person. We do this in two ways - using indicator screwdriver and multimeter. And in the end, we'll talk about whether it is possible to find the phase and zero without devices and how to do it.

How to determine the indicator screwdriver

An indicator screwdriver is a device with a transparent handle, inside of which there is a capacitor bulb, and the end of the handle is a conductor. It looks like this:

The principle of operation of such an indicator is simple. You insert a screwdriver into the socket, and if you hit the phase and press the contact plate on the handle, then you increase the capacitance of the capacitor at the expense of your body - the neon light is on. The phase is easy to find. But zero, even if there is voltage in it - no. It does not happen there more than 60 V, and below this threshold, the indicator screwdriver will not show anything. This is not necessary: ​​when the light bulb lights up only when it comes into contact with the phase, such a screwdriver is the best phase determiner.

More advanced versions of indicators (with LED, sound signal and batteries) are not helpers here: they will also show a lower voltage. If you show it, then even with the magnitude. And to determine this value, we better use a multimeter. But it is best to use such indicators to search for hidden wiring. There are more advanced devices for this purpose. Some of them react to the field created alternating current, others - on the metal in the wall. But all these devices have a different scope, which is beyond the scope of this topic.

Searching with a multimeter

This is not difficult. To begin with, let's set the function on the switch of your tester (either this sector will be called ACV, or it will be V ~) with a limit above 220 V. For someone it will be 500, for someone 800. Testers are different. We insert the black probe into the common socket (COM is written next to it), and the red one into the socket for measuring current, voltage and resistance. It is not necessary to put it in a socket for working with a ten-ampere current, you most likely do not have it there. Then we insert both second ends of the probes into the socket holes. If it is working, the display will show the value of your voltage - from 220 to 230 V.

It remains to find out where the phase is. We insert the red probe into one of the outlet holes, and either hold the black one with our fingers or connect it to the ground, for example, to a central heating battery (find the place where the paint fell off, or clean it off a little). If you hit the phase, then the display will show an effective voltage of about 220 V. And if it is zero, then you will not see more than 60 V (more often - no more than 30 V).

Determination of phase and neutral wires for installing a three-phase socket

This situation can happen in the house with Soviet-made electric stoves. You have five wires, they are the same color, the socket will be unbalanced, and we need to know exactly where the three phases are, where is zero, and where is the ground. And this is important - all kinds three-phase sockets we are asymmetrical.

Here you need a little help. If we have 220 V between one phase and neutral, then between two phases with a shift of 120 degrees (2π / 3) 220 will need to be multiplied by the square root of three, and we will get an effective voltage of 380 V.

So we stock up on colored markers, a piece of paper and a pen, and begin to solve the puzzle. We mark the insulation with markers different colors, we are looking for phases in the same way as in ordinary socket, write down the results on a piece of paper. It will be relatively easy to distinguish three phases. And then you need to find zero and ground. If grounding is done correctly, then the voltage in it will be zero, and there will be several tens of volts in the neutral.

To control, we measure the voltage between the phases. It should be 380 V, and between zero and each phase should be 220 V.

Another interesting use of a multimeter

The tester can be used to search for hidden wiring in an apartment if it is energized. Usually this can be done without it, if the wiring is carried out according to the rules. In this case, you can navigate junction boxes. Worse, if you got the apartment after a home-grown renovation, when everything superfluous was simply covered with plaster.

For wiring detection you will need a tester and a KP303 transistor (another field one is also possible).

Set the switch to about 200 kΩ. Insert the probes into the standard position (COM and universal jack) and connect their ends to the source and drain of the transistor. A wire antenna can be wound around the shutter. If there is a live wire in the wall, then it will create an electromagnetic field, albeit a small one, which will change internal resistance transistor.

If there are no appliances

But what if you don’t have either a tester or an indicator screwdriver? How to determine the phase and zero without instruments? It turns out that this is possible.

True, before doing this, look at your shield: maybe you don’t have to do anything. If the house is new and the wiring in it is done according to the rules, then the wires can be identified by colors. So, zero is made blue, phase is any other color, and ground is yellow-green. Also pay attention on the circuit breakers (like small switches): they must be in phase. If you unscrew the outlet and see the ground in its place, then most likely you didn’t confuse zero with the phase of the electrics either.

In general, there are household methods for diagnosing wiring, here are some of them:

1. using a probe;
2. with the help of potatoes;
3. using old fuses and pliers;
4. "with bare hands.

For obvious reasons, we will not discuss the last three.

Using a Probe

A probe is an incandescent lamp in a cartridge with two wires brought out. It is not entirely ethical to advise this method of verification: this method is prohibited by the instructions. You should not use it in situations where you do not know how many phases are carried into the room and where everything turns on and off.

But sometimes you have to use a probe. For example, to distinguish zero from ground in the absence of sockets (we are considering a situation where sockets are not installed, and three wires stick out of the wall).

Recently, three-core wiring has been installed in residential premises. If electricians have neglected the rules of color, you can distinguish where zero is and where the earth is with the help of a probe. To do this, you need to turn off one of the zeros in the shield, if you do not know which one is real, and check the performance of the future outlet. If you turn off zero, then the sockets will not work, and the light will not light up - the apartment ground is not connected to the circuit. And when the ground is disconnected, the light bulb will work.

What not to do

In fact, you already know the basic rules for working with wiring., but some I would like to repeat.

1. Do not grab the multimeter probes by the bare parts. I hope I don't need to explain why.
2. Some citizens have a habit of seeking concealed wiring with bare hands. If you are one of those, there is no point in dissuading you. But you can give advice: do it with the back of your hand. If you get electrocuted, you will bounce off the wall, otherwise you risk not letting go of the exposed wire due to a cramp.
3. Sometimes it is possible to measure resistance, rather than voltage, to indicate zero and phase. Be careful: when operating the tester in this mode, do not close the phase to ground, as a short circuit may occur.

In order not to get into situations in the future when you have to sort the wires, I would like to advise you to mark them. In the future, it will be easier for you to repair and connect electrical appliances. Well, be sure to get an indicator screwdriver. It costs a penny, but a necessary tool in the household. Believe me, the order in your shield and the security of the power supply to your home are worth a lot.