The socket shows both phases. How to install the socket correctly, and on which side should the phase in the socket be? Incorrect connection of the switch to the chandelier

In the normal state of the electrical wiring in the outlet, one contact has 220 Volts, and the second is not energized. This is ideal... Sometimes the indicator can show two phases in the socket at the same time.

To a novice electrician or amateur, such a situation may seem absurd, but it is reality. In some violations, this is exactly the picture observed.

Single-phase current of 230 volts is supplied to residential buildings. According to this diagram, it turns out that two phases cannot appear in the socket. In older buildings, the wiring is made of two-core cables. Along one line (phase) the current goes to the consumer, and along the other (zero) it returns.

With such a circuit, the reasons for the appearance of two phases in the plug connector may be different. New houses have grounding, which can cause accidents only if there is unqualified intervention in the electrical circuit of the home.

Break of zero at the input

If the zero wire in the incoming cable is disconnected, the lights in the apartment will go out and electrical appliances will stop. Checking with an indicator will show the presence of a phase on each contact of the socket. The classic question arises: “Who is to blame and what to do?”

In the absence of zero, the current searches for a free line. If the lamp is turned on, it does not light, but the phase through the filament passes to the neutral wire, then to the bus, and from there to the neutral line of sockets. The phase can also come from a device connected to any plug connector in the apartment.
Now there is a phase on each socket of the socket. The indicator emits a light signal when each contact is touched.

A multimeter helps to easily clarify the situation. If you measure the voltage difference between two phases, the device will show a zero value. It is clear that this is the same phase. It is enough to turn off the lamps and disconnect the devices from the sockets and the second phase in the socket will disappear, because the voltage and neutral supply lines do not have other connection points.

It is necessary to restore the incoming zero line. It is possible that the wire has simply become disconnected from the bus. This problem can be dealt with even at home. De-energize the apartment by opening the phase input and check the absence of voltage. Insert the neutral lead into the terminal and tighten the screw.

Breakage of the neutral wire in the junction box or in the wall

Sometimes a zero break occurs in the junction box. In this case, part of the apartment's wiring is functioning normally, but the line connected to this box is inoperative. It is enough to find where the zero broke off or burned out and restore the connection.

It happens that two phases appear in the plug connector due to damage to the neutral wire inside the wall. The cause of the malfunction is negligence when drilling holes. If you break the insulation by breaking through the wire, the neutral conductor will be welded to the phase conductor. In this case, there will also be two phases in the outlet. It is necessary to lay a new line or open the damaged area and repair the wiring.

Automatic protection on the zero line

In old houses, protective devices are installed at both phase and neutral (nowadays such a connection scheme is prohibited). If an overload occurs, it is possible that the circuit breaker will operate only on the zero line. The consequences are the same as if the zero broke off or burned off.

Induced currents

Everything works fine, but the indicator detects voltage on each pin of the plug connector. Moreover: the device shows two phases in the socket when the power supply to the entire apartment is turned off. This completely unrealistic situation can happen if a high-voltage power line runs near your home.

This is the so-called pickup or, to put it more correctly, induced voltage. Even experienced electricians can get confused here. Work in this case is associated with a high risk of electric shock, so only professionals should perform it.

When electrical wiring fails, it sometimes happens that the indicator shows two phases in the socket, but electrical appliances do not work.

This type of malfunction is quite common, but a novice or inexperienced electrician can puzzle over it for a long time.

Let's consider this situation. You drill into a wall by plugging the drill into an outlet. The hole had almost been drilled, when suddenly the machine went off on the counter.

You turn on the machine, but as a result, not a single electrical appliance works. Check the socket - in both sockets the indicator indicates the presence of a phase. What does this all mean?

Why are there two phases in the socket?

Only one phase. The socket must have one phase and zero, and in the above situation, the indicator indicates the presence of the same phase in both sockets of the socket.

The most likely cause of the malfunction in this case is damage (break) of the neutral wire going to the socket during the process of drilling the wall.

The presence of a phase where zero should be is due to the fact that it passes through a load - a constantly on light bulb or some other electrical appliance.

As a rule, all neutral wires in a house or apartment are closed to the neutral bus of the electrical panel, the phase will appear in the socket. This is very easy to check - you just need to turn off all electrical appliances in the apartment.

Why, after disconnecting all electrical appliances from the network, are there still two phases in the outlet?

So, you have turned off all electrical consumers from the sockets, turned off all the switches, but they are still present. The reason for this may be the following.

During the drilling process, the zero was broken by the drill and short-circuited. The same situation can occur during a short circuit, when the braiding of the wires melts and the conductors short-circuit.

In any case, it is necessary to turn off all electrical appliances, then inspect the drilling site and eliminate the malfunction.

Reason for appearance two phases in the socket may be the most trivial - this can happen simply because a fuse (plug) has blown or the circuit breaker on the electrical panel has turned off.

Is it possible for a situation to actually appear in an outlet? two different phases? The author of this article once encountered this. At the same time, the TV, refrigerator and several light bulbs burned out, since the voltage between different phases was really 380, not 220 volts.

The reason was the short circuit of one of the three phases running along the overhead power line to the neutral wire (this happened in the private sector).

In order to have reliable information about the presence of phases and voltage in the network of your apartment, one phase indicator is not enough. To measure voltage, it is better to purchase a combined device - a multimeter that measures voltage, current and resistance.

For home needs, the cheapest one is suitable.

In any case, we must not forget about safety measures, since even through a load you can get a very noticeable electric shock.

Electrical wiring is done according to simple principles that are studied in school, but some faults often go beyond standard ideas about the operation of the electrical network. Two phases in an outlet is a common problem that regularly confuses users with insufficient experience in electrical wiring repairs.

Where and why the second phase may appear

Here we must immediately make a reservation that since only one phase wire enters the apartment, the concept of “second phase” implies that the voltage indicator shows the phase in the contacts on which it should initially be at zero. The second phase, in the correct understanding of these words, cannot exist in an apartment.

The next point that you need to know to understand the essence of the problem is that every electrical appliance is a conductor of electricity. The simplest example is a light bulb - its filament glows due to the fact that it is a conductor of electric current. Essentially, the light bulb shines because it closes phase and zero between each other, but a short circuit does not occur since the filament has a certain electrical resistance. Other devices work in the same way - they are often connected to the network through transformers, the windings of which are made of copper wire. Again, a short circuit does not occur, since due to the length of the wire and its cross-section, it has electrical resistance, but in essence, when a plug of any device is inserted into a socket, the phase and zero are closed in it.

Now it should be clear why there are two phases in the socket - this malfunction can only appear if zero is missing. The phase comes to the socket, passes through the electrical appliance connected to it and appears on the neutral wire, and from it on those sockets that are located after the zero break. Accordingly, if you turn off all the switches and remove all the plugs from the sockets, the indicator will show the phase on only one contact.

As a result, a phase instead of a zero may appear in one separate socket (provided that it is double or triple and a plug of some electrical appliance is inserted into one of the plugs). Further, 2 phases can be in one of the rooms, in half of the apartment, or generally everywhere.

You also cannot discount the possibility of a short circuit, for example, when drilling a wall or poor-quality laying of wires in a junction box. With some luck, you can hook the wiring in such a way that the neutral wire is cut off from the main network and stuck to the phase wire. In this case, the indicator will show two phases in the outlet even when electrical appliances are disconnected from the network.

In this video you can see how this malfunction is reproduced on a specially assembled stand:

Two phases in one socket

Such a case practically never occurs - it is a rare exception that confirms the rule. If this happens - all the other sockets work flawlessly, there is light everywhere, and in one single socket the indicator shows two phases, then first of all the socket itself is disassembled. The breakdown will most likely be in another place, but first, just in case, you need to make sure that it is not in the place that is easiest to get to.

If you're lucky, a broken, burnt-out, or jumping-out wire will be found in the socket box.

When the outlet is working properly and without any signs of overheating of the wires, the next step is to determine how it is connected - directly to the junction box or through another outlet. In the second case, there is a possibility that the neutral wire was poorly screwed into the “parent” socket and has now fallen out.

Next, the junction box is checked - this is the most likely place where a bad connection can be found. Here we must take into account that the phase wire is not so demanding on the quality of the twist - if the connection is bad, it heats up, but still works for some time. The neutral wire can oxidize without any visible consequences - to see this you will have to unwind the twists, strip the wires again and put everything back together.

If the twisting is in order, then all that remains is to ring the wire with a tester - if it shows a break inside the wall, then for repairs you will have to break the groove.

When an outlet stops working in a house where the wiring has been done recently and according to all the rules, then it is additionally worth checking whether it is a power outlet to which a water heater or similar powerful device is connected. In this case, the reasons must be sought in the main distribution panel, from where it can be powered, bypassing the distribution boxes.

Two phases in several sockets

The situation is similar to the previous one, but now in several outlets at once, often located in the same room. In this case, the lighting may or may not work, depending on the method of its connection.

There is no point in checking the sockets here, with one exception - if they are all connected by a so-called cable. In this case, the wires from the junction box come to one of them, and the rest are connected in series. The PUE strongly does not recommend doing this, but anything can happen.

The procedure for troubleshooting depends on the desire to climb into the junction box and whether there is a possibility of a daisy chain connection. Most likely, a broken wire will be found in the distribution box, but if all the connections there are normal, then you need to disassemble all the sockets in the room one by one.

Two phases in half the rooms

This happens if the distribution boxes are connected in series one after the other. What to do in this case - the solution is standard - you need to sequentially go through all the boxes in search of bad contact.

The whole difficulty is that often there is no connection diagram, so it is not known from which room and into which of them the wiring is laid. You should also take into account the option that the contact can burn out both in a room in which the sockets do not work, and in the previous one according to the diagram, where the indicator shows normal voltage in the sockets.

There is a solution so as not to disassemble the terminal boxes in all rooms - you can change the phase and zero on the input panel, and then use a voltage indicator that can show the phase through the wall. Before doing this, you need to make sure that there is no grounding anywhere in the sockets and, just in case, disconnect the grounding, if one is connected.

Two phases in all sockets

If the lights in the entire house are turned off, and the voltage indicator shows two phases in the sockets, the problem is most likely on the input panel.

In this case, you must also check the ground wires in case they are grounded. At the same time, until you are sure that there is no voltage on them, you should not touch the grounding contacts with your bare hands and prohibit children from touching sockets and electrical appliances.

In old houses, plugs or circuit breakers are often installed not only on the phase, as recommended by the latest editions of the PUE, but also on the neutral wire. The burnout of such a plug is equivalent to a break in the zero, so it is recommended to check them first.

It is also necessary to take into account the possibility of the absence of an electrical panel as such, when the wire from the meter goes directly to the main distribution box - the faulty contact may be in it.

To understand what phase and zero are in a socket, an ordinary person (not a specialist) does not need to delve into the electrical jungle. As an example, let's take a regular plug socket that receives alternating current.

There are two electrical wires going to the outlet - neutral and phase. Current flows through only one of them - the phase phase (also called the working phase). The second wire is neutral (or zero phase).

Zero and phase in old sockets

To connect the old outlet, use two conductors. Some of them are blue (working neutral conductor). This wire carries current from the source of electricity to the household appliance. If you grasp the live wire but do not touch the other wire, you will not receive an electric shock.

The second wire in the socket is a phase wire. It comes in a variety of colors, including blue, green-yellow or light blue.

Note! Any voltage exceeding 50 volts is life-threatening.

Phase and neutral in a modern socket

Modern devices have three wires. The phase comes in any color. In addition to phase and neutral, there is one more wire (protective neutral). The color of this conductor is green or yellow.

Voltage is supplied through the phase. Zero is used for protective zeroing. The third wire is needed as additional protection - to draw in excess current during a short circuit. The current is redirected to the ground or in the opposite direction - to the source of electricity.

Note! It makes no practical difference whether phase and zero are located on the right or left. However, most often the phase is located on the left and the zero is on the right.

Determining phase and zero with a multimeter or screwdriver

Multimeter

The device is a combined electrical measuring device capable of performing several functions. The minimum configuration includes a voltmeter, ohmmeter and ammeter. Some modifications are made in the form of current clamps. Both analog and electronic meters are available.

To begin the measurement process, you must switch to AC voltage measurement mode. Measurement is carried out using one of several methods:

1. We clamp one of the existing probes with two fingers. We direct the second probe to the contact, which is located in the switch or socket. If the data on the monitor is insignificant (does not exceed 10 volts), we are talking about zero. If you touch another contact, the indicator will be higher - this is a phase.
2. If there are concerns about touching the dipstick, there is another way. We direct one of the rods into the socket. With the second rod we touch directly to the wall next to the outlet. The result will be approximately the same as in the case described above.
3. There is a third way to measure using a multimeter. We touch the probe to a grounded surface (for example, the equipment body). We touch the surface to be measured with the second probe. If the wire is a phase, the multitester will detect a voltage of 220 volts.

The indicator is a simple way to determine the phase, accessible even to a person who is doing this for the first time. The test screwdriver looks like a standard one. The difference lies in the internal structure of the indicator screwdriver. The screwdriver handle is made of special transparent plastic. There is a diode inside. The upper part is made of metal.

Note! The indicator screwdriver must not be used for purposes other than its intended purpose. It is not intended for loosening or tightening screws. Improper use of the test screwdriver will cause its failure.

To find phase and zero using a screwdriver, you need to perform the following sequence of operations:

1. Use the end of a screwdriver to touch the contact.
2. Press the metal button at the top of the screwdriver with your finger.
3. If the LED lights up, we are talking about a phase. If it doesn't react, it's zero.

Note! An indicator lamp rated for 220-380 volts will glow at voltages greater than 50 volts.

1. Do not touch the bottom end of the screwdriver while taking measurements.
2. Keep the screwdriver clean, otherwise there is a high risk of insulation damage.
3. If you need to determine the absence of voltage, first check the functionality of the device, which is definitely under voltage.

Advice! In a DC network, the polarity of the contacts is determined in a very simple way. To do this, simply immerse the wires in a container of water. Bubbles will begin to form near one of the wires - this is a minus. The second wire is positive.

An indicator screwdriver should not be confused with a dialing device. The dialing screwdriver is equipped with batteries. When working with such a device, you do not need to press the button to determine zero and phase, since the screwdriver will light up in any possible situation.

About a common wiring fault when both connectors of a 220 V socket have phase. About why this happens and why it is dangerous. From the first person and a little informal.

There is one characteristic electrical wiring fault that can confuse a novice or inexperienced electrician. To explain what I’m talking about, I’ll quote a story from one of my friends:

“A neighbor comes to me on Saturday - a lonely grandmother. And asks to sort out the electrics in the apartment. They say nothing works, but the lights don’t seem to have been turned off.

Well, of course, I go out onto the site and check the circuit breakers. Everything is in order, all machines are turned on. I take the indicator: it passes. I go into my grandmother’s apartment and check the first outlet. The first connector is “phase”. I check the second connector - it’s also “phase”! What nonsense!

I move on to another outlet: the same picture. Two phases. Where do the two phases come from? Well, let’s say, okay, “zero” may disappear. But where can the second phase appear in a 220 volt outlet? Only one phase is connected to the apartment.

I didn’t understand anything, I apologized to my grandmother, and she had to wait until Monday for an electrician from the housing office. I still didn’t understand what the trouble was.”

I immediately ask the experts not to laugh at my friend’s story. He is not a stupid person at all, just not an electrician by profession. And I will shed some light on the dark story that happened to him.

If the hero of the story also had a tester with him, and he knew how to use it, then he could make one interesting observation. There was no voltage between the two “phases” in the socket. This means that the “phase” was of the same name. This is understandable, otherwise the equipment and lamps in the apartment would be in trouble.

But where did the “phase” come from on the conductor, which was previously zero? It simply passed through the load, that is, for example, through the bulb of a corridor lamp, which is always on, and... that’s all. It turned out that she simply had nowhere to go further. The reason for all the chaos is that the input zero working conductor is broken. It can simply break off at the zero bus in the shield; for an aluminum wire this is as easy as shelling pears.

When this happens, the current in the circuit, of course, disappears. No current - no voltage drop. Therefore, the “phase” is the same both at the input and at the output of the light bulb. It turns out that there is a “phase” in both wires. Well, since all the neutral wires of the apartment are directly connected to each other on the same neutral bus of the apartment panel, the “lost phase” appears in the socket too. It was enough to turn off all the switches and unplug all the appliances in the apartment for the anomaly to disappear.

Well, to correct the situation, it was enough to clean and reconnect the fallen neutral wire, having first, of course, turned off the introductory packet.

It is worth noting here that, although the “phase” on the neutral conductor in such situations seems illusory and unreal, it can pose a very real danger. Even under a load, you can get a very good “shock”, because a person only needs about 7 milliamps for very unpleasant sensations.

Again, in order to avoid such situations, it is impossible to manufacture electrical appliance housings directly at the point of their connection, without a separate grounding line and re-grounding. After all, if you neglect this prohibition, then if the neutral wire breaks, you can get a phase directly on the device body, albeit “not quite real.”