How to make ground in the country

construction of a private house, or countryside cottages are always associated with a large volume of electrical work.In this range of problems, along with the AC input to the house, installing switchgear and protective equipment, install an extension, no less significance is the well-planned and executed by the grounding system.Unfortunately, during the « samostroya » inexperienced owners about this point quite often overlooked or even deliberately ignore it, trying to reach some kind of false saving money and labor.

Meanwhile grounding system is extremely important - it is able to prevent a lot of trouble, which may lead to a very sad or even tragic consequences.Under existing rules, grids experts will not make a connection home to the power lines if the system is not in the house, or she does not meet the necessary requirements.And the owner, anyway, have to decide on how to make ground in the country.

In modern homes urban ground loop is required to provide more

on building design stage and its internal communications.The owner of the private property that question have to decide for himself - to invite experts or to try to do everything with their own hands.Afraid it is not necessary - all this is to be feasible.

Why do we need ground loops

to understand the importance of ground, enough basic concepts of school physics course.

vast majority of private homes powered by a single-phase AC 220 .The electrical circuit required for all devices or equipment provided by the presence of two conductors - actually, the phase and neutral conductor.

design of all electrical appliances, tools , household appliances and other elements provides insulation and protective equipment that must be prevented from entering the voltage on the conductive housing or covers. Nevertheless , the probability of such events never eliminated - isolation can be broken discharge from the burn unreliable , sparking contacts in wiring connections can damage the circuit elements and the like . In this case, the phase voltage can get on the housing, a touch which becomes extremely dangerous to humans.

particularly dangerous situation, if with such a defective device are metal objects with so-called natural ground - heating risers, water or gas pipes, exposed reinforcing elements building designs and etc .At the slightest touch to them chain can be closed and deadly current pass through the human body in the direction of a smaller building.No less dangerous in this type of situation, and if the person is standing barefoot or wet shoes on a wet floor or the ground - also has all the prerequisites for circuit AC circuit from the enclosure.

one expression of the properties of the electric current that he always chooses the conductor with a minimum of resistance.So, you must pre-create a line of least resistance and zero potential on which in the case of short voltage will be discharged.

resistance of the human body - vacillates, and depending on the individual characteristics and even the temporary state of a person.In practice, this electrical value is usually taken for 1000 Ohm (1 Ohm ).Therefore, the resistance of the grounding circuit should be repeatedly below.There is a complex system of calculations , but usually operate values ​​of 30 ohms for household power private homes and 10 ohms if the ground is still used and as protection against lightning.

may argue that all problems can be resolved by setting special protective devices (RCDs).But for the correct operation of the RCD ground it is also a necessity.When even the slightest leakage current circuit almost instantly closes and the unit works by turning off the dangerous area household power.

Some owners are in prejudice, that ground is sufficient to use water pipes or heating.This is - an extremely dangerous and absolutely unreliable . First , to ensure efficient removal of stress is impossible - tubes can be strongly oxidized and does not have a sufficiently good contact with the ground , and addition , they often come in plastic sections.It is not excluded and loss shock when at kosnovenii to them in case of breakdown of the power supply to the body, and such danger can be exposed including neighbors.

Most modern appliances once equipped with a power cord with three-prong plug.Appropriate socket must be installed and at work assembling the wiring in the house.(Some appliances are older models instead contact terminal on the housing to connect the ground).

There are strictly defined color « pinout » wires : Blue wire is clearly "zero" phase can have different colors, from white to black , and grounding- always yellow-green .

So, knowing this, some "wise" owners, wanting to save money on upgrading the wiring and arranging full ground, just do in outlets jumper between terminal and ground zero.However, this they do not solve the problem, but rather exacerbate it .When certain conditions, such as blown or poor contact of the working zero in some part of the chain, or random perefazovke , phase capacity will appear on the device, and it can happen in the most unexpected place home.Risk of electric shock is increased in this situation many times.

conclusion from all the above - ground structural element is mandatory home electrical network.It performs functions at once:

• effective removal voltage leakage current-carrying parts, the touch which can cause electric shock.
• potential equalization in in seh objects in the house, for example, grounded appliances and heating pipes, water supply, gas supply.
• Ensuring the correct operation of all the installed systems and safety devices - fuses, breakers or RCD.
• Equally important is the ground and to prevent accumulation in the housings of household appliances static charge.
• particular importance it takes on for the modern electronics - especially computers.For example, the work of switching power supply of computers is very often accompanied by the induced voltage on the system case.Any discharge may cause damage to the electronic components, malfunction, loss of information.

Now that the importance of grounding system explained, you can go to the issue of how it do private home conditions independently.

What are the grounding system in private houses

So competently executed grounding system must provide a reliable potential-free contact of the earth and with the least possible resistance created circuit.However, GRU nt - c CNT in strife - its different types seriously differother resistivity:

soil type	soil resistivity (ohm × m)
Sand (when groundwater level is less than 5 m)	1000
Sand (whengroundwater level above 5 m)	500
fertile soil (humus)	200
moist sandy loam	150
semi-solid or forest type loam	100
Cretaceous layer or semi-solidclay	60
Grafitovyen shale, clay marl	50
loam plastic	30
plastic clay or peat	20
Underground aquifers	from 5 to 50

Obviously, those layers that have the lowest resistivity, usually located at a considerable depth.But at the burial of the electrode and the results may not be enough.This problem is solved several ways - by increasing the depth of installation of pin electrodes to increase their number, spacing or the total area of ​​contact with the ground.most commonly used in practice a few basic schemes:

• scheme "and» - recessed installation metal closed loop on the perimeter of the house.As an option - shallow scored pins, connected by a ring bus.

In suburban construction is used infrequently because of the large volume excavation or in connection with the arrangement of the buildings on the site features.

• Diagram "b" is perhaps the most popular with the owners of suburban housing.Three or more moderately buried interdigital electrode of a bus - this design is easy to do yourself, even in a limited space.
• Scheme "in" shown with one ground electrode set at a greater depth.Sometimes, such a system even arrange building basement.Driving is comfortable, but not always executable - it virtually impossible to implement on stony soils.In addition, for a grounding system is necessary to use special electrodes - it goes about it below.
• scheme "g» - quite comfortable, but only if it was thought still at the stage of designing the house, and performed during pouring of the foundation.Embody it to life on the finished building will be extremely profitable.

So, the easiest way to implement a minimum "B" circuit costs or, on opportunities "in."

Grounding with homemade metal parts

To make the grounding system of the type , require metal profiles, welding machines, earthmoving, sledgehammer.In some cases, in difficult dense soils, may need a manual drill.

Schematically, this system looks like this:

place location of buried electrodes is chosen so calculation , that was most convenient to take the bus to the grounding distribution box.The optimum distance from the house - 3 - 6 meters.Permissible limits - no closer than one meter and no further ten.

dimensions indicated in the diagram, are not some kind of dogma.So, side of the triangle can be before three meters in length, and the driving pin depth can be somewhat lower - 2,0 ÷ 2, 5m .The number of electrodes can also vary - if GRU nt pl otny and to a greater depth to hammer the pins did not manage to , you can increase their number.

Common Council - in advance, call your local power supply for obtaining advice on the implementation of the grounding circuit.These experts probably have designed and tested in this circuit region.In addition, they can help to calculate the size and on the basis of the planned power load home - is also important.

What can serve as electrodes?For these purposes, most commonly used with steel corner shelf 50 × 50 mm and a thickness of not less than 4 ÷ 5 mm.They can be used pipes, better - galvanized with a wall thickness not less than 3.5 mm.You can take a steel strip with a cross section of about 48 mm² (12 × 4), but it harder to drive vertically into the ground.If you decide to use a steel bar, that the is better to take a galvanized, diameter 10 mm.

To tie pins in one circuit, use a strip of 40 mm × 4 mm or rod 12 - 14 mm.This material is suitable for laying the ground bus to the input point her inside the house.

• So, initially made markings on the chosen place.

• then it is advisable to dig a small pit target shape to a depth of 1 meter.Minimum depth - 0, 5m .At the same time a trench dug to the same depth - for her from the circuit to the cap goes home ground bus.

• The problem can be simplified somewhat by digging not continuous pit and a trench along the perimeter of the loop created.The main thing is that their width is allowed to freely conduct clogging electrodes and welding.

• Prepare electrodes desired length.Edge, they will hammered into the ground, you need to sharpen sander, cut off at an angle.The metal should be clean, unpainted.

• The planned ground electrodes are driven into the ground with a sledgehammer or elektromolota .Bury them so that a trench (trench) they project above the surface level of approximately 200 mm.

• After all electrodes are clogged, of associated common bus (horizontal earthing) of the metal strip 40 × 4 mm.There is only applicable welding, although it is possible to meet the recommendations do bolting.No, to provide reliable and durable grounding the harness necessarily welded - threaded contact, placed under ground, quickly oxidized, loop resistance will increase sharply .

• Now you can lay the bus from the same strip to the foundation of the house.The tire is welded to one of the goals of the electrodes and laid in the trench and then she comes to the base of the building.
• tire is attached to the cap.