How to make a safe grounding in the apartment, if it is not
Method number 1 - Connecting an RCD
If there is no grounding in the apartment (not provided by the developer), but you still want to protect yourself from electric shock, then it is best for a while connect a residual current device (in the photo below). This device, of course, will not solve the whole problem, but nevertheless, in the event of leakage of currents, it will instantly turn off the power to the serviced device — a washing machine, water heater, or a group of outlets.
In addition, we recommend that you yourselfreplace wiring in the apartment to a new one with a three-wire cable. In the future, when the time comes to make grounding at your entrance, you will already be prepared, and all that remains is to conduct and connect the PE wire to the corresponding bus of the floor plate.
Method number 2 - Installation of your own circuit
Recently, there have been frequent cases when residents of prefabricated houses decide to independently ground in Khrushchev, for which they organize an individual grounding circuit. This idea is that from the apartment to the basement stretches a PE single-wire wire along the risers. Near the house, at least three metal corners or electrodes are driven in, interconnected by a metal plate. To the finished protective triangle (provided in the diagram below), a wire drawn from the floor is connected, the other end of which is fixed to the shield body. All that remains is to connect the grounding of the apartment with the shield and, as you know, leakage protection is ready!
We draw your attention to the fact that you can do such grounding with your own hands only after coordinating this event with the management company. Spontaneous adoption of this decision can lead to many problems, because You, no matter how, intervene in the approved project, and if some kind of accident occurs, it is possible that you will be the extreme.
I would also like to add that if you still decide to make your own ground loop in the apartment, then PE wire must be copper, section not less than 4 mm.kv. This method of protection is suitable not only for residents of the first floor, but also for everyone else - the 4th or even the 5th.
Video review of the security system:
Dangerous protection option
Some unfortunate electricians decide to make grounding in the apartment, simply by connecting the third wire to the water supply or heating system passing through the room. In no case do not use this version of the grounding circuit, as in this case, the picture is as follows:
- there is a breakdown of current on the body of the appliance (boiler or washing machine in the bathroom);
- dangerous current passes to the batteries and hot / cold water risers of not only your apartment, but also of all neighbors, as the system is single.
- anyone who at the moment decides to drink water from the tap or just touch metal pipes can be a victim.
By the way, this point is stipulated by the rules of the PUE and is also strictly prohibited, according to the PUE 1.7.110 (see Chapter 1.7).
In addition to this method of grounding the apartment, the following are considered unsafe:
- Connection in the zero socket to the ground conductor (the so-called grounding) If something happens zero wire break in the network, the dangerous voltage will go to the case of all electrical appliances connected to the ground of the apartment - a computer, water heater, refrigerator, etc.
- Serial grounding of electrical appliances (through each other). If you decide to make such an earthing circuit, be aware that in the event of an accident, electromagnetic incompatibility can occur. Electrical installations will interfere and there is a high likelihood that the ground loop will not prevent electric shock.
- Connection of several wires to one PE bus terminal. It is allowed to connect one conductor to each contact pad. Neglecting this rule is strictly prohibited.
That's all you need to know about how to make grounding in an apartment, if it is not. Nevertheless, we strongly recommend using an RCD as a temporary protection option, and insist that the city authorities take care of upgrading the wiring in your home.
Fulfillment of one's own ground loop in the TN - C system, without metal connection with the ground loop of the power substation, actually means switching to the CT system. In the case of an apartment building, such a transition is prohibited by the PUE. If even the resistance of the grounding loop of the power substation is 4 Ohms (it is always always really lower) and the resistance of the completed ground loop is 4 Ohms, but it is always real better, the phase loop resistance is zero 2 Ohms, it is usually less, then the resistance of the current path of the circuit to the case of the grounded electrical installation a phase wire with a voltage of 220 volts will be 4 + 4 + 1 = 9 Ohms, and a current value of 220/9 = 24.444 amperes. For the operation of circuit breakers this current is not enough, only circuit breakers with a rated current of 6 amperes somehow satisfy they create by the magnitude of their tripping current which should be three times the rated current of the circuit breaker, but their tripping time will not provide a safe tripping time to protect a person from electric shock. And the touch voltage on the cases of grounded electrical installations is -24.444 * 4 = 97.777 volts and the current through the human body will be 98/1000 = 0.098 amperes or almost 100 milliamps, that is, a deadly current. The only measure of human protection in this case is the installation of an RCD. If, however, your own con ur still connect the grounding metallic bond with the contour of the supply substation, it will only re-grounding neutral conductor, a purely technical measure to avoid dangerous voltages at the load more than 240 volts with zero breakage provoda.Odnako by grounding split point PENa conductor to working zero and a protective conductor, this helps to prevent the appearance of zero voltage on the enclosures of voltages higher than 240 volts. The circuit breaker has insufficient speed to protect a person from electric shock, the only real measure of protection is the installation of a residual current device. the neutral wire of currents and other consumers connected after the place of breaking the neutral wire. In the TN-C system, the PUE prohibits the installation of RCDs in two-wire inii, but it is possible to install it as fire protection and to protect against human shock by electric current in electrical installations connected with water, with sufficient resistance of the leakage current path through the water to operate the RCD, with a five-fold value of the RCD setting current. The use of the TN-C-S system has most of the shortcomings of the TN-C system and, due to the use of a protective conductor, in the case of unskilled service, it can carry a potential of 220 volts even to serviceable electrical installations connected to the protective conductor in the event of a protection failure or an open circuit protective conductor lines. The same applies to the TN-S system. That is, protection against electric shock to a person should be necessarily comprehensive - technical means plus organizational measures.
Only re-grounding and the 5th PE conductor from the ASU to all the floor RS on the housing.
N bus in the floor RS isolated from the housing.
Otherwise, an individual grounding circuit or an RCD or a differential transformer.
There should be no other.
Do not take sin into your soul.
In the TN-C-S system on the ASU of the house there must be high-quality re-grounding at the PEN separation point with the connection of all conductors to different bus terminals, and nothing else. Combined zero without such grounding, I would not start in my apartment. It is easy to get unpredictable voltage across instrument housings when a common zero break. And in this case, neither RCDs nor automatic machines will protect against electric shock. I don’t know that they found a bad thing in installing an RCD in TN-C. In fact, this is the only way to protect against electric shock during the breakdown of the insulation of power receivers operating in such a system. In the presence of an RCD, even with grounding to the water supply, the current through this circuit cannot exceed the trip current of the RCD. As a result, with an RCD of 30 mA and a grounding resistance of 7 kΩ, the circuit will already be disconnected. If the pipes are not plastic, their resistance to the ground is usually substantially less. And nothing bad will happen to a neighbor holding a pipe. Worse, when pipes use all sorts of morons who steal electricity as a working zero.
I suggest that if there is no grounding in the old panel house, then you can do the following, use a puncher below the floor, find fittings in the wall to which you need to weld a bolt and remove the ground, this is the most reliable option ... ...
Vladimir, read the SNiPs, what kind of wall panels there are, what kind of fittings are and how they are protected from corrosion, embedded elements and lifting loops, how the plates are fixed and whether at least some part of the fittings can be grounded. Mortgages and hinges can simply anchor into concrete, have no connection with other metal elements. With the same success, you can weld a grounding bolt to a sports weight in your room.
Regarding the RCD, it must be connected only with a grounding circuit, and preference at the installation site - immediately after the counter, in front of the machine. switch. If wrong, correct me.
And even so, why can’t you ground yourself to the riser? Let’s say the metal riser goes into the ground as it should, why should I break a person (a riser neighbor) with electric shock, because the currents will go where I need the riser to the ground?
In the water parking lot, some of the pipes can be replaced with polypropylene pipes. In new apartment buildings, parking lots are now installed only from plastic pipes. Therefore, grounding on the water supply system may not work at all, or even dangerous.
The riser is already connected to the potential equalization system (SOE), and that is grounded.
The article explicitly says that the grounding in the apartment is dangerous, to get burned, all electric stoves in panel houses are zeroed, what does the article offer to tear off all these “zeros” and leave the stove without grounding and grounding before it is electrocuted? 🙂
So the only way out is to mount your own ground loop and set it off?
There is an opinion that it is possible to set it off even without grounding it will still leak, only through you 🙂, for a start you will get a little electric shock, but it will turn off anyway, maybe this is the best way
Is it possible to ground on a cast-iron sewer riser?))
Unlike steel water pipes that are welded together, cast-iron risers consist of cast-iron pipes inserted one into another, and no one can guarantee the reliability of electrical contact and the value of resistance.
Electrical installations with voltage up to 1000 volts must be powered by the TN system (TN-C-S and TN-S) (see PUE, p. 1.7.57). Now decipher the abbreviation TN (see PUE, clause 1.7.3): T - grounded neutral, N - open conductive parts connected to the grounded neutral of the power source (i.e., zeroed - protective grounding is performed, see PUE, p. 1.7.31). Protective grounding of conductive electrical enclosures is carried out only in IT and TT systems, and we mainly encounter a TN system. In the TN system, the main protective measure is automatic power off, which is provided by current circuit breakers and protective grounding (note, not grounding). Additionally, in the TN system in multi-apartment buildings, a potential equalization system (CES) is installed, which has its own grounding, the purpose of which is to create a zero potential of the system (since the "ground" has zero potential). This grounding is not standardized; therefore, it is not a classical grounding of conductive housings, although it is electrically connected to them. And, in general, the case grounding in the TN system is useless, because it is shunted by grounding, which means that it will not work effectively. Allowed in TN systems, the use of RCDs. Grounding for RCDs is not necessary: whoever doubts, read the principle of operation of RCDs.
In the old apartment, electricians do not want to look for a leak, they offer to ground the bath to the floor. Tell me, will it happen?
you can still ground the electrician. What do you think - will a good ground contact be on concrete? It will succeed, but mediocre.
In the APARTMENT, the earth goes from the rh to one outlet (an unknown one did in antiquity), later, when replacing the water supply pipes, they threw a wire along the pipes (I don’t know what kind of wire, most likely the land) now I change the wiring. where to get the land more right, from the shield at the entrance or from the wire along the risers?