How to make a grounding loop in a private house with your own hands: grounding diagrams and installation instructions

The construction of a country house includes a lot of electrical work.Not least among them is the planning and arrangement of a grounding system, which cannot be ignored for safety reasons and the requirements of PTEEP.

Doing grounding in a private house with your own hands is not prohibited, so in this material we will consider in detail the main stages of design and installation of the circuit.

The meaning and necessity of grounding

The basis for the energy supply of a private home is the electrical network, which poses a danger to residents if some measures are not taken to eliminate it. Such measures include double insulation of conductors, potential equalization, RCD installation and difavtomats.

Grounding the electrical network also plays an important role and is designed to divert electric current that appears in an unnecessary place into the ground.

Technically, it looks like this: all electrical installations in the house are connected to each other and to circuit breakers, and then to the ground, so that in a critical situation there is somewhere to dump excess voltage

One piece of reinforcement or profile driven into the ground is not enough. Grounding is a whole system of interacting elements connected to other systems.

It cannot be installed without selecting suitable parts according to the parameters and without making preliminary calculations.

To install the structure into the ground, you need to select a small open plot of land next to the house. A building or garage cannot be erected over it, since preventive or repair opening of the soil will be carried out periodically

There is a difference in the design of grounding systems between urban high-rise buildings and private housing.

In apartment buildings, the bus is located in the floor electrical panel, while for a private house the ground loop is literally buried in the ground, since it is located nearby and does not require much effort for installation.

All requirements for the design and installation of a grounding system are set out in PTEEP 2.7.8. The owner of the house should know that the commissioning of a self-equipped structure will be carried out by the organization that supplies electricity.

Its representatives are required to visually inspect the above-ground visible parts of the system every six months, and approximately once every 12 years to excavate the soil and check the condition of the underground elements.

Selecting a system and drawing up a diagram

There are three grounding systems in total: TT, IT, TN, of which the latter is divided into three more varieties - TN-S, TN-C, TN-C-S.

In private housing construction, TN-C-S or TT system designs are usually used, and TN-C-S looks more attractive since there are fewer requirements for its installation.

Scheme of the TN-C-S grounding system: 1 – symbol of the power supply grounding conductor; 2 – open conductive parts. At a certain section of the circuit, the grounding conductor is connected to the PEN

The system starts from the main grounding bus, which is installed either in the electrical panel of the house or in the input device cabinet.

The most rational solution is when the grounding is located on a support that redirects the electric main into the house.

Electrical box diagram with separated grounding and neutral conductors: 1 – electrical panel; 2 – neutral conductor; 3 – grounding conductor; 4 – phase group conductors; 5 – differential current switch; 6 – automatic machines; 7 – group chains; 8 – differential automatic; 9 – electricity meter

Diagram of a CT system, which is radically different in the connection of the grounding conductor. It does not depend on a power source and operates autonomously

The TT system is used much less frequently. This is handled by representatives of the energy supply organization, and if the owner still decides to save money and carry out the installation himself, then the same Energosnab employees will come to certify the documents.

If you still take a risk and choose a CT grounding scheme for a private house, then do not forget about the mandatory installation of RCD!

Grounding Installation Instructions

There are two ways to assemble and install underground grounding structures. The first can be done on your own, although you will have to work hard and spend a lot of time, and the second can only be done by professionals, since it will require special equipment and skills in measuring resistance.

Option 1 - ground wire + ground electrode

First, let's look at how to do grounding yourself in a private house, without resorting to paid services. The system consists of two main elements, each of which is selected depending on the installation conditions.

Ground wire – copper conductor with a cross-section equal to the cross-section of the phase conductor. One end of it is connected to a bus located in the electrical panel, and the other is connected to a ground electrode buried in the ground. Grounding conductors from all of them also lead to the bus. electrical installations in the house.

Ground wires are easy to recognize by their color marking - yellow-green polymer insulation. Method of fastening to the bus – screw, by installing tips

Ground electrode - This is a structure made of steel elements, in close contact with the ground and serving to equalize potentials when voltage occurs.

When designing, soil resistance parameters are taken into account, the dimensions of the rods and frame are calculated, as well as the burial depth.

Soil resistivity. Obviously, the value of the SSG of sand, clay or peat differs. The wetter and denser the soil, the less voluminous the ground electrode structure will be.

There is a universal design, the creation of which does not require complex calculations.

To make it you will need:

• three 3-meter corners 50*50 mm or steel pipe with a wall of 3 mm and a diameter of 16 mm;
• three 3-meter corners 40*40 mm.

You will also need welding machine, cutting tool, sledgehammer, fastening materials, and for excavation work - a shovel and bucket.

Step-by-step instruction:

1. We dig a trench from the house to the installation site of the ground electrode. Its depth and width are about half a meter.
2. We make markings for driving in pins (corners) in the form of an equilateral triangle with a side of 3 m.
3. At the vertices of the triangle, we dig holes 50 cm deep.
4. We connect the pits with narrow grooves along the perimeter to form a triangle.
5. We drive 50*50 corners into the ground so that parts about 0.2 m long remain above its surface.
6. We weld three 40*40 corners in the shape of a triangle.
7. We weld the triangle to the corners driven into the ground.

Then we connect the grounding conductor to the structure: we press its end with a round tip and, using a bolt of a suitable size, screw it to a hole drilled in one of the corners.

Ground electrode installation diagram. The conductor leads from the buried triangular structure to the house and ends in the electrical panel on the grounding bus

Metal parts must be covered with soil, preferably sand, and the installation site of the ground electrode and conductor must be marked with a sign so as not to be damaged during construction or household work.

Recommendations for selecting parts and installing the ground electrode into the ground:

Food salt is dangerous for steel rods and the strip connecting them - it corrodes the metal and renders the structure unusable. Make sure that this substance does not accidentally get into the ground near the ground electrode.

Option 2 - modular pin system

If the structure can be made from rolled metal parts with your own hands, then a factory pin must be purchased at the store.

Its main advantage is the absence of labor-intensive excavation and welding work, and the disadvantage is the additional costs of paying for the services of a service organization.

Installation diagram of a pin grounding switch and its structure. The main components are the head, a steel electrode with electrochemical copper coating and couplings connecting the electrode fragments

The greater depth is also explained by the fact that in the specified range there is usually groundwater present, which sharply reduces the resistance of the device, and this is a necessary condition for creating a grounding system

In a homemade design, the area of ​​contact with the ground is increased by using several corners.There is only one pin here, so the increase in contact occurs due to its length. The device is driven into the ground to a depth of 20-40 m.

Excavation work comes down to digging out one hole with dimensions of 0.5 * 0.5 * 0.4 m. It is not recommended to use an impact drill to drive the pin, since rotation of the pin head must be prevented. Here you need a hammer drill with a special attachment.

In the factory kit, along with the pin, there is a clamp for attaching the grounding conductor, so the installation process consists of hammering in the main device and connecting it to the wire.

Step-by-step instructions for installing a pin grounding switch. Only a specialist - a representative from a service organization - can measure spreading with a multimeter and calculate the installation depth

There are standards that must be followed during the installation process:

• for 3-phase network 380 V – resistance no more than 2 Ohms;
• for 1-phase 220 V network – resistance no more than 4 ohms.

When installing it yourself, to be on the safe side before the inspection authorities, it is better to accurately calculate the level of groundwater and make sure that the ground electrode will drop to this level.

Upon contact with groundwater, the resistance parameters will return to normal.

Conclusions and useful video on the topic

Do-it-yourself grounding experience:

Practical tips for installing a factory-made ground electrode:

Installation of a multi-rod grounding system:

As you can see, you can install the grounding system either with your own hands or with the help of a team of invited electricians - the first method is cheap, but more complex, the second is expensive, but reliable.

However, the main thing in proper installation is the result, which should make the home’s electrical network completely safe for its owners.

Do you still have questions about setting up your own ground loop? Ask them below under the article - our experts and competent site visitors will try to help you.

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