Categories: Electrician at home, Electrical connection of equipment, Electric installation work
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Connection of an electric stove and a washing machine in the TN-C system

 

Connection of an electric stove and a washing machine in the TN-C systemThe TN-C electrical grounding system has long been outlawed and banned for use. But it is easy to ban, but what about those whose homes were commissioned long before the introduction of new norms and rules?

Indeed, for the operating organization, the modernization of the common house wiring and bringing it at least to the TN-C-S system is an overwhelming waste of time, effort and money. And therefore, people living in old-built houses often face the challenge of incorporating modern household appliances into a two-wire network with a TN-C grounding system. And most of the questions arise when connecting powerful devices with a metal case.

The latter relates, first of all, to the electric stove and the washing machine. So, how do you enable these devices in your TN-C home network?


We connect an electric stove in TN-C

The sequence of actions is as follows:

1. Determine the location of the plate. The stove is considered a stationary electric receiver. Moreover, its power is relatively large. Therefore, to install the plate on the nearest wall, a special socket with an increased current rating (usually 32-40 amperes) with a grounding contact is mounted. For a three-phase network, the socket will contain 5 contacts, and for a single-phase network, three.

2. We install a separate circuit breaker of characteristic C in the apartment panel to power the stove. For a three-phase cooker and the same network, a three-pole circuit breaker with a value of about 16 amperes will be required, and for connecting a stove in single-phase mode, you need a single-pole circuit breaker with a rating of 25-32 amperes.

3. Mount the cable to connect the plate. For a single-phase plate it will be VVGng 3 * 4, and for a three-phase plate - VVGng 5 * 2.5, since in the latter case the current load will be less. Pull the cable from the apartment panel to the socket of the stove. We will talk about the methods of laying and installing the cable later.

4. Connect the cable to the outlet and close its cover. At this stage, you must be very careful. In order not to make mistakes and not to confuse ourselves, it is better to do everything in accordance with the standards: in a three-core cable we connect a brown core (it may turn out to be white) to the phase socket of the outlet, a blue core (white with a blue stripe) to the working zero connector , well, to the ground connector - a yellow-green core. In a five-core cable, phase conductors are usually white, red and brown.

The phase connectors of high-rated current sockets do not have any markings. The connector for the working neutral conductor is marked with the Latin letter N (neutral). The connector for protective grounding is marked with a special symbol “ground” (a vertical line perpendicular to the long horizontal, below which are horizontal parallel lines of shorter length in descending order).

Observe connector markings and color marking cable cores - Technically, it is not always a mandatory measure, except when the N connector is more powerful to absorb a greater current load.

5. Paying attention to the marking of the electrodes of the plug and observing the color marking of the cores, we connect the plug to the flexible cable of the electric stove. Here, everything is similar to connecting an outlet.

6. Connect the flexible cable of the plate to its rear panel. Much depends on the model of the plate and the number of phases in the network. We talked about this in detail in a previous article (How to independently connect an electric furnace and a washing machine) The ends of the flexible multi-wire cable, before installation in the terminal clamps, are preferably tinned to achieve reliable contact.Again, pay attention to the color coding of the cores and the marks on the terminals of the plate. Most electric stoves have a wiring diagram for single-phase and three-phase modes on their rear panel. Such a scheme can be of great help.

7. We cut the cable for connecting the stove in our apartment panel, we clean the ends. We connect the phase conductors to the pole clamps of the circuit breaker, and we "plant" the zero working core on a common bus where all the zero conductors are connected. Only one thing remains: what to do with the yellow-green vein? In the TN-S system, it connects to the ground bus. But what if we have a TN-C system?


Grounding plate in TN-C

Very often, even professional electricians when working in the TN-C system allow themselves such liberties: they ground the instrument case to a working zero bus. This is dangerous because when the working neutral conductor breaks, the "phase", passing through the load, will be on the "grounded" case, which will almost inevitably lead to electric shock.

In addition, a situation is possible when the electricians of the service organization confuse and interchange the zero working and phase conductors. In this case, when grounding to the working zero, we will not have Grounding and, if I may say so, "phase lock." The result may again be an electric shock at the most unexpected moment.

But to provide the body of the electric stove with protective grounding is still necessary. Otherwise, due to aging of the insulation of the internal conductors, the housing of this device may still acquire a dangerous electrical potential. Therefore, we take such actions:

1. You can find out if the housing of the electrical panel of your apartment has reliable grounding. Such information can be provided by the operating organization: Housing Office, Homeowners Association, etc. If they answer you in the affirmative and assure you that the shield body is grounded, then the yellow-green cable core can be safely connected through a bolt to this same housing. But if the case is not grounded, or if the employees of the operating organization cannot clearly answer your questions, then you should not "put" PE on the shield case. Such grounding can be ineffective or even dangerous for the reasons mentioned above.

2. If the apartment is located on the ground floor, then, as an option, you can consider installing your own, individual grounding device. The manufacture of this device is best entrusted to specialists, since it will require a work not only of electrical, but also of welding. A multi-wire wire in yellow-green insulation is removed from the apartment panel to the street, which is terminated by a tip. The cross section of the wire is chosen equal to the cross section of the phase supply conductors.

The grounding device itself is installed in the ground behind the external wall of the building, which usually consists of three steel bars with a length of at least 2.5 meters and a diameter of at least 16 mm. These bars are connected by a steel strip of 5 * 40 mm.

From a grounding device up to the level of the grounding conductor, a wire rod of 8 mm in diameter is output. The wire is terminated by a welded plate with a bolt hole. The wire rod is bolted to the grounding conductor from the apartment at a height of at least 2.5 meters from the ground.

In the apartment panel newly mounted ground wire sits on a separate zero bus, which becomes PE. To this bus and connect the grounding conductor from the electric stove.

Such a grounding system is already called TT and will cost a lot. The main thing is to remember that the resistance of the grounding device is strictly standardized and should not exceed 8 ohms for a single-phase network. It is unlikely that they will be able to measure this resistance on their own, so there is no way to do without hired labor.

3. Attempts to ground the electric stove on the pipes of cold water or even sewage, hot water or heating is better not to be made. Although these pipes must be grounded, no one actually controls the resistance of their grounding.Thus, it is possible not only to make an ineffective grounding, but also to harm your health or the health of neighbors. The same can be said about grounding from other utilities: ventilation shafts, elevator shafts, etc.

4. If nothing happens with grounding (the shield is not grounded, CT cannot be grounded), then we leave the yellow-green wire plugged in the shield until better times. In relation to the stove we take a number of actions.

We place the stove in such a place to exclude the possibility of simultaneous contact with its body and live parts that are not energized. We are talking about a metal mixer, sink for dishes and, of course, pipes of hot and cold water. Near the stove itself, it will be nice to provide a dielectric flooring. Of course, a dig in the kitchen is already too much, but an ordinary dry rug will not hurt.

In the absence of grounding, instead of a conventional circuit breaker, it is better to use a differential circuit with a tripping rating of 30 milliamps. Such a switch can save you when the leakage current from the stove body flows through your body (if this happens).

In any case, in the absence of grounding on the body of the electric stove, you must be extremely careful during its operation. If the stove is not in operation for some time, then it is better to completely turn it off from the power outlet.

Electric stove

We connect the washing machine in TN-C

Connecting a washing machine to the TN-C has only a few features. First of all, regardless of the possibility / impossibility of grounding the machine, you must connect it through a differential circuit breaker, since the washing machine is usually installed in the bathroom. And the bathroom is a room with increased danger. The differential switch, as in the case of the stove, is installed on an empty spot in the apartment panel. The required rating of the machine is 16 amperes, the differential tripping current is not more than 30 milliamps.

Three-phase household washing machines are not found in nature, therefore, to connect the “washer”, it is enough to install a regular 16 amp socket with curtains and a grounding contact. Cable connecting this outlet and difavtomat in the shield, it will be three-core - VVGng 3 * 2.5.

If it is not possible to ground the housing of the washing machine in the TN-C system, precautions against it are even more necessary than with respect to the hob. It is better to plug in such a washing machine only for the duration of its use. Moreover, during the operation of the machine, it is better not to take a shower and not to touch the body of this household appliance.

Alexander Molokov

We recommend reading:How to make the washing machine not shock

See also at e.imadeself.com:

  • How to connect the washing machine to the mains
  • How to install and connect a socket for a stove and a washing machine
  • How to independently connect an electric furnace and a washing machine
  • How to connect an induction cooker - useful tips
  • Ground wire - cross-section, marking, color, connection, requirements for charging ...
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    Comments:

    # 1 wrote: | [quote]

     
     

    1) since The power of the plates lies mainly in the range of 7-12 kW, then for 7 kW a 3x10 cable is needed. In an extreme case, 3x6. It is not permissible to select only by current. Accordingly, the current of the machine must be selected (see passport on the stove);
    2) in most old apartments, and in new ones without email. plates, 5-6 kW are allocated. And connecting email. plates will not only turn off the opening machine, but may also cause a fire. Even if people at their place replaced the wiring - the riser and panels in the entrance are not designed for higher power;
    3) you cannot install differential or ouzo in the TN-C system, as no third core;
    4) It is not recommended to do remote grounding. God forbid an emergency will happen - everyone will hang on the performer. And officially - you need to order a project, coordinate;
    5) if you make a separation to obtain 3 wiring - grounding is normalized and is 10 ohms (see PUE).

     
    Comments:

    # 2 wrote: | [quote]

     
     

    Konstantin, Hello. I will answer you point by point.

    1.3 amps per square. Is this for copper? Where did you see the plates connected with a ten or six? Actually, in practice, a universal (for a single-phase or three-phase network) 7/10 kW power plate is connected by a four and the cable does not even heat up during open installation in the box. This is a personal experience, if that. And about "it is unacceptable to choose by current" I did not even understand the phrase. And why else choose a cable? In kilowatts? So they also need to translate into current ....

    2. If the stove is not provided for in the apartment, then in Irkutsk, in particular, all the permissible power is 3 kW. And we need to decide what exactly happens when the stove is connected - turning off the machine, or a fire. Both that, and another at once are hardly possible.

    I wrote an article for those who have already decided that the stove in his apartment will fit in power. And about those who have had gas in their apartment all their lives, a separate conversation.

    3. Oh, oh? Very controversial statement. I dare to disagree with him and I will find supporters. Of course, an RCD in a two-wire system will be less effective, but it certainly will not be superfluous.

    4. And I do not recommend everyone to arrange remote earthing. This is an extreme measure when there is no other choice. And if you grounded the washing machine with a separate device, what could be worse than the absence of any grounding at all? What kind of emergency are we talking about?

    5. I have another digit in my memory - 8 Ohms for a single-phase network and 4 Ohms for a single-phase network. However, you made me doubt - I will clarify and unsubscribe.

     
    Comments:

    # 3 wrote: | [quote]

     
     

    With remote earthing, a potential difference may occur. Re not no more 30 ohms.

    1.7.101. The resistance of the grounding device, to which the neutrals of the generator or transformer are connected or the conclusions of the single-phase current source, at any time of the year should be no more than 2, 4 and 8 ohms, respectively, at line voltages of 660, 380 and 220 V three-phase current source or 380, 220 and 127 V single-phase current source. This resistance must be ensured taking into account the use of natural earthing, and also grounding conductors of repeated grounding of the PEN- or PE-conductor of the overhead line with a voltage of up to 1 kV at number of outgoing lines no less than two. Resistance of an earthing switch located in close proximity to the neutral generator or transformer or output of a single-phase current source, must be no more than 15, 30 and 60 Ohms, respectively, at line voltages of 660, 380 and 220 V of a three-phase current source or 380, 220 and 127 V of a single-phase current source.

    1.7.103. Total flow resistance grounding conductors (including natural) of all repeated grounding of the PEN conductor of each overhead line at any time of the year should be no more than 5, 10 and 20 Ohms, respectively, at line voltages of 660, 380 and 220 V of a three-phase current source or 380, 220 and 127 V of a single-phase current source. Wherein the spreading resistance of the ground electrode of each of the repeated grounding should be no more 15, 30 and 60 Ohms, respectively, at the same voltages.

     
    Comments:

    # 4 wrote: Alex gal | [quote]

     
     

    Regarding the use of TT grounding in a high-rise building.

    There is no direct ban on this, but there is an indirect one. For example PUE

    1.7.55. For grounding in electrical installations of different purposes and voltages, geographically close, you should usually use one common grounding device.
    Let me remind you that: Words "usually"means that this requirement is prevailing, and deviation from it must be justified.
    The reason for such requirements is simple: a dangerous voltage can occur between a separate ground and grounded building structures (which are connected to the building ground through an equalization system). Safety rules require that you exclude the possibility of simultaneous contact with electrical appliances and structures connected to different grounding systems.That is, if you connect the washing machine from a separate ground, then you must exclude the possibility of simultaneous contact with the washing machine and water pipe, heating battery, etc.
    In this case, if the voltage appears on the machine body, then the RCD will work and there will be no problems. But if the voltage appears on some structures of the house, then no RCD will protect a person. Well, for example, let’s imagine that part of the house’s pipelines was lined with plastic pipes and thereby disconnected from the building’s ground, and some of the residents used the pipeline to ground it. Or even as a zero wire :) with a certain unhealthy intent ... The case may be rare, but it cannot be ruled out. Replacing pipes with plastic ones inside the building by tenants independently is a common thing. Replacing the underground water mains with plastic ones is also a common thing, but we remember that it was always one of the allowed natural grounding conductors, and in general there are more questions than answers to grounding conductors in old buildings.

     
    Comments:

    # 5 wrote: Author | [quote]

     
     

    Thanks to everyone for the comments, but once again I ask you to pay attention to the fact that, firstly, I did not recommend a separate memory to anyone as the best way out. And secondly, for the calculation and installation of the memory, it is necessary to invite specialists who will carry out the necessary approvals. If each owner of the apartment will do their own grounding, then yes - the problems are almost guaranteed.

     
    Comments:

    # 6 wrote: Dmitriy | [quote]

     
     

    A gas stove in the picture, by the way!

     
    Comments:

    # 7 wrote: andy78 | [quote]

     
     

    The picture shows a gas hob and an electric oven (electric oven).

     
    Comments:

    # 8 wrote: ser | [quote]

     
     

    During repair, I removed my washing machine from the bathroom to the former pantry. Now you can calmly wash with a working washer. Previously, these were problems. Had to wait or turn it off while using the bathroom. I connected the washing machine as follows: in the panel there is a separate automatic machine for 16 A, an RCD for 30 mA, a copper cable in the pipe through a hole in the wall and a separate outlet in the pantry in a convenient place for 16 A. I did everything in an hour. It was lucky, since the pantry with the washing machine was almost behind the shield. I did not use the third wire of the cable, since it is not in the floor shield, and I didn’t want to invent anything with grounding. And you can’t do it. After upgrading the riser with the shield I will use all three cores of the cable. I liked the article. A lot of useful practical information. Although I do not agree with what was written on the grounding of the washing machine. But here everyone does at their own peril and risk. I prefer not to take risks with improvised grounding and I do not advise others!

     
    Comments:

    # 9 wrote: | [quote]

     
     

    If there is no grounding, that is, wiring in two cores, then you do not need to invent anything. Put the differential. machine and there will be no problems.
    A simple video example of connecting a washing machine in the TN-C system: http://www.youtube.com/watch?v=iI1ZpUkBClo&feature=plcp

     
    Comments:

    # 10 wrote: | [quote]

     
     

    Alexander. I want to draw your attention to the fact that connecting the case of any electronic device to a separately made grounding device will not solve the problem. Even if the resistance is 8 Ohms, then the fault current will be 220/8 = 27 A. For instantaneous operation of the machine, this is a meager quantity and the machine is useless here. Only UZO which can be installed before the outlet from which the electrical device is powered can help out. For the operation of the RCD, only 0.03 A is sufficient. Then, when the phase closes on the body of the electronic device, the current will go to your home-made ground and the RCD will disconnect the faulty electronic device. For reliable operation of the RCD under the most adverse conditions, a ground resistance of 57 Ohms is needed. Recently, on your site, I published my article where I spoke in detail about this. (Electrosafe private residential building and cottage) Sincerely.

     
    Comments:

    # 11 wrote: Author | [quote]

     
     

    For Mironov S.I: Regarding the RCD, you are certainly right. Moreover, regardless of the grounding system - protection against leakage currents is needed. After all, the washing machine is usually in the bathroom, and this is a room with an increased risk of electric shock.

     
    Comments:

    # 12 wrote: | [quote]

     
     

    Alexander. In fact, in the TN-C system, according to the PUE p. 1.7.80, it is forbidden to put RCDs. If necessary, it is allowed only for individual power consumers and then, with the necessary conditions, how to do it. Each house must be dealt with individually. For example, if it is an electric stove to which three wires from the shield fit - phase, zero and earth, then putting an RCD to protect the electric stove is a waste of money, because when a phase wire is shorted to the case, the machine will work and eliminate the accident. Another thing is a washing machine. If three wires were laid for the electric stove during the installation process, then for the washing machine, usually the owners without further ado install the outlet by connecting it to the phase and zero. In this case, the following options are possible. The first option is only the phase and zero in the outlet. Then, during the short-circuit phase, the machine does not work on the washer case, since there is no large current necessary for its operation. If a person touches the body of the washer - he will receive an electric tram. In the second case - again, without further ado, they empty the washing machine housing (they connect the housing to zero). Then, during a short-circuit phase to the case, the machine will work and prevent an accident. But here another trouble is very likely. If the neutral wire breaks in the riser, the phase appears on the washer housing. Therefore, the most acceptable way in this case is to install an RCD of a 10 mA outlet. Plug it into the outlet to which you previously connected the washer, and already to the RCD of the outlet - the plug from the washer. In this case, when the phase is short, nothing will come to the washer body until a person touches the washer case. Then the person will be shocked by the current and with a probability of 95% he will remain alive. These are unvarnished facts. Well, in order not to get completely under voltage, it is necessary to ground the washer housing, and it is also correct to ground it. Sincerely, S. Mironov

     
    Comments:

    # 13 wrote: Author | [quote]

     
     

    For Mironov S.I: in fact, the use of RCDs for a washing machine in a 220 volt household network is not prohibited. And what kind of RCD it will already be: as part of the outlet, or a separate device in the shield - there is no value.

    Then: in a two-wire network, a short to the case cannot be considered short for obvious reasons.

    And finally: you are too keen on the role of captain "Evidence." Fair.

    Sincerely, Alexander

     
    Comments:

    # 14 wrote: | [quote]

     
     

    From my answers it is clear that I am not against RCD in a two-wire system, but I want only one thing - that a person really understands what awaits him and what could be the consequences if he used it incorrectly. What will be the RCD - as part of the outlet or separately standing in the shield, it may matter. A two-wire network is an old worn electrical wiring. Here we are faced with the fact that there is no protective PE wire in it and therefore installing an RCD (and not connecting the washing machine to the PE wire) will shock the person with the current and with what current - there is a difference in 10 mA or 30 mA. It is clear that 10mA is safer than 30 mA. It is not possible to set the RCD to 10 mA in the shield, since such an RCD will constantly turn off the network due to leakage currents. Therefore, we will be forced to install a 30 mA RCD in the shield. But we understand that the bathroom is a dangerous room and by installing an RCD of 10 mA in the outlet of the washing machine, we thereby additionally protect ourselves from electric shock. Next, two-wire is a TN-C system in which it is required to nullify the open conductive parts (HFC) of the electrical receivers, therefore, from this point of view, it is quite appropriate to consider insulation damage with the subsequent closure of the phase wire to the HFC as a short circuit. And the last one. An electrician - it's like a miner - makes a mistake once.For 40 years of work in this area - I knew deaths and what at first glance seems obvious - sometimes it turns out to be completely wrong. And also the electrician - this is such an area in which you need to study all your life and still this will not be enough. Please do not be offended by me for obvious reasons. Sincerely.

     
    Comments:

    # 15 wrote: Author | [quote]

     
     

    Mironov S.I., You are not reporting anything new at all, but you are issuing instructive footcloths on a split screen. This is a little annoying, frankly. Sorry if hurt.

     
    Comments:

    # 16 wrote: | [quote]

     
     

    As for removing the stove away from the washbasin, bathtub, etc. - isn’t it easier to carry out potential equalization? And as for the probability of a zero conductor breakage, it did not convince me that the probability of a phase falling on the case is much higher, so my personal opinion is that it is necessary to zero even in the TN-C system, but without fail with potential equalization, with a sufficient cross section of the conductors there will be a mini GZS.

     
    Comments:

    # 17 wrote: Timothy | [quote]

     
     

    Dear author, you were absolutely rightly pointed out your mistake (And what kind of RCD it will be: as part of the outlet, or a stand-alone device in the panel - it does not matter), writing that the RCD in the panel with a certain length of line will turn off just like that, that you stubbornly reply "you are not reporting anything new." So, do not mislead people, and do not upset people who correct you correctly.

     
    Comments:

    # 18 wrote: Author | [quote]

     
     

    Timothy: why did you get that in a working network

    RCD in the shield at a certain length of the line will turn off just like that

    ? In general, nothing "just happens", and such things - even more so. And am I then misleading people after this?

     
    Comments:

    # 19 wrote: | [quote]

     
     

    Please tell me, is it possible to make grounding on an electric panel not from an electric panel, but from the street from the circuit, remove the strip and weld it by welding?

     
    Comments:

    # 20 wrote: ABYRVALG | [quote]

     
     

    Very often, even professional electricians when working in the TN-C system allow themselves such liberties: they ground the instrument case to a working zero bus. This is dangerous because when the working neutral conductor breaks, the "phase", passing through the load, will be on the "grounded" case, which will almost inevitably lead to electric shock.

    If the neutral is combined with protective wires (ground) throughout the mains, such a system is called and designated TN-C.

     
    Comments:

    # 21 wrote: | [quote]

     
     

    Hello. I live in a one-room apartment in the old Khrushchev. Wiring in the house is an old two-core TN-C. I myself am an engineer but not an electrician and for me it is a little new, although of course I am familiar with the basic principles. At home, I like to do everything myself and, if possible, delve into everything in more detail.

    I have a huge request for help with advice. I am married and have a little daughter, God forbid someone will be shocked. Grounding in the electricity network of the apartment is not at all. A washing machine is in the kitchen and is plucked with electric current. During the repair in the apartment, I replaced all the old two-wire wiring with a 3-core VVG 2.5. But at the same time, the green ground wire in the apartment is not connected to anything. At the entrance to the electrical panel are two modern 25A automatic machines on 2 lines going to my apartment on my apartment. Electricians themselves putting advised precisely 25A. 1 line goes to the hall (TV, computer, iron, vacuum cleaner), and the second to the kitchen (fridge, washing machine, food processor and plan to put a 2000W boiler).

    Because you won’t reach our electricians, but I’m afraid to climb into the electrical panel on the landing and the wiring from the apartment to this shield is still old, I think I’d leave automatic machines at 25A in the switchboard (do not put new difavtomats in their place), and right in my apartment the first razvetkorobku I want to put an RCD on each line of 25A, leak 30mA. Grounding (green wire) I still want to bring to the body of the electrical panel on the landing.I have no other choice - a multi-storey building, although I know that this threatens to burn out zero.

    Questions: 1-is my idea correct or can I somehow refine it? 2-is it necessary, in spite of the automatic machines (in the shield on the landing) and the RCD, which I want to put at the entrance to the apartment, to put an additional machine and RCD (or difavtomat) on the boiler and washing machine? If so, how many amperes (maybe 16A)?

     
    Comments:

    # 22 wrote: Author | [quote]

     
     

    Dmitry, perhaps, is easier to get by with a socket combined with an RCD in one building.

     
    Comments:

    # 23 wrote: | [quote]

     
     

    Thanks to the author for the advice. As far as I understand, you mean the installation of an RCD combined with an outlet for such dangerous devices as a boiler and a washing machine. The fact is that according to the passport they need yet put on their own machines at 16A. I don’t know if it’s necessary if I already have automatic machines, even at 25A, before entering the apartment. If nevertheless necessary, then in the apartment panel you will have to put on them one automatic machine at 16A and then lead to each device in a separate line. Still somehow complicated, I would like to simplify as much as possible.

     
    Comments:

    # 24 wrote: Author | [quote]

     
     

    It is advisable to have a separate line for such power consumers. But, as they say, without fanaticism.

     
    Comments:

    # 25 wrote: | [quote]

     
     

    In general, the problem of grounding is a headache for many houses built in the USSR, and not only Khrushchev's, but also 9 floors, built in the 80s of the last century. Particularly unpleasant is the fact that grounding is absent in houses equipped with electric stoves. And as a power cable, builders put 3x240mm2 in an aluminum sheath, and this same sheath plays the role of a zero conductor. It should also be noted that the cooperative houses that I took for maintenance were built on a former swamp, and the groundwater level is about 30 cm. I constantly hammer the chairmen of cooperatives about the need to urgently draw a circuit to ground the introductory electrical switchboard, since this has already happened more than once that the sheath of the cable, lying almost in water, in some places dissolved, and the grounding of the input switchboard disappeared. At the same time, the power engineers caused by me rested for a long time, did not want to repair the cable - they say, there are 3 phases, what else do you want? And at the same time, a huge phase imbalance appeared: there could be about 150 volts on one phase, about 270 volts on the other, 200 on the third. And the potential difference of the case of the floor electrical switchboard and water pipe reached, sometimes, 50 volts. I just can’t get the chairmen of cooperatives to get a communication plan in the territories adjacent to the houses. (And according to my estimates, a 10 kV cable should go somewhere.) And they don’t want to finance the order for the grounding device for private companies - it's expensive, they say.
    I’m writing all this not with the aim of seeking advice, I just got sick, I wanted to share my problems with someone.

     
    Comments:

    # 26 wrote: | [quote]

     
     

    Vladimir,
    In theory, the contour beats along the perimeter of the building at a distance of 2 m from its walls, along with a cable of 10 kV there should pass gas, water, sewage, communication, and possibly in several "instances" and places. The cable can be detected with C.A.T. and punch it, for everything else you need to contact the regional gas, city water supply, etc. In addition, to equip the circuit, you have to dig a trench 0.9m deep

    If you are at home servicing the ASU, then you must also contact the power company. company. Most likely, the border of their balanced accessory will be located on the cable ends in your ASU. Those. power cable is their property.

     
    Comments:

    # 27 wrote: | [quote]

     
     

    Hello! Tell me please.
    I need to connect two comfortable electric stoves with an oven in a private house in which there is no grounding, is it enough to drive a 2-meter corner in the basement of the house and bring a wire from it to the outlet?

     
    Comments:

    # 28 wrote: | [quote]

     
     

    The issue of electrical safety during the operation of household electrical equipment in the TN-C system was raised by the author quite justified. The number of devices connected by the population is constantly growing, their power is increasing.

    In conditions when it is impossible to create conditions of complete safety in accordance with the EMP in a house (apartment) with an old system, the author proposes to apply additional measures (remember basic and additional protective equipment?), It is realistic, albeit slightly, to increase the degree of safety of people in the existing operating conditions technicians. It is clear that the proposed measures do not fully comply with the requirements of the PUE, but this does not mean that nothing needs to be done.

    I believe that potential equalization, grounding, the use of RCDs on outlets in hazardous areas, the use of reasonable measures to additionally isolate individual parts of the equipment to prevent accidental contact by people and other possible measures - all this, increasing the person’s chances for the safe operation of the equipment, have the right to implementation.

    I live in a rural house with a two-wire network, and I consider the issues of electrical safety to be constantly relevant. In addition to the washing machine, electric stoves there is electrical equipment in the garage, in the workshop with far from dry floors. There is a water pump in the well. Power tool for working on the street.

    What is the author reproached for? For his desire to explain to people what the danger of electric shock in their home consists of, and how to reduce this danger?

    I fully support the position of the author.

     
    Comments:

    # 29 wrote: | [quote]

     
     

    In the same power supply network, it is forbidden to ground the housings of some power consumers through a separately made grounding device without connecting to the neutral wire, and to null others' housings. Those. we can ground the machine, it will be local or repeated grounding, but at the same time, grounding must also be performed.

     
    Comments:

    # 30 wrote: | [quote]

     
     

    Panel 9-storey, two-wire TN-C system, in the apartment the line to the electric stove has 3 (aluminum 6 sq.) - conductor, 1-phase, 2-zero, 3-? What is the name of this conductor? In the switchgear, these 3 conductors are connected 1- phase, 2- ground bus, 3- ground bus, 2 and 3 are connected together. This is done in all such houses. What role does the 3 conductor play and what should I call it?

     
    Comments:

    # 31 wrote: Ruslan | [quote]

     
     

    I’m the same kettle as you, but I think working zero. That is, on the case of your varilny working zero.