human body - almost water with dissolved salts in it.Some say 60% of the water, the other - 99 ... Let's leave it, what is important: a man electrically conductive!That is, he is able to conduct current through itself.And if the current is strong enough, in the body there are sometimes irreversible processes leading to death.
Let us carefully consider what force current can kill in any case it is quite unpleasant.I experienced it myself, did not modern, more than a dozen times.Causes of early childhood - ignorance, and then - the usual Russian and perhaps apathy.
So what happens when a person touches the bare conductor under voltage?It depends on situation.If we imagine such a person is hanging in the
completely different situation when a person is standing barefoot on the wet ground and grabs the lead.It creates a closed circuit: the power transformer - & gt;Wire - & gt;People - & gt;Land - & gt;and again transformer.And then the earth?Despite the fact that the winding of the transformer is also grounded in a certain way, and the earth - a great conductor.
and even not necessarily bare feet and wet earth.And shoes crude - also a conductor, and a concrete floor, and tile, and even waterproofing does not give guarantees.And by this closed circuit ran electrons, while the accident rolled his eyes and went to shreds frothing at the mouth.Well, if he is in the throes unhooked from the wire, but often just the opposite: more squeezed his crooked fingers.In general, a nightmarish picture.
and crows also not sdobrovat if there are too many on the wires meet, and even start to swing its wings.I once watched from this coven crow feathers fly only because they themselves short two wires, thereby creating a closed circuit again for the current flow.
electrics, by the way, the rules of safety are provided not only insulating gloves and insulated tools, but also insulating mats, boots.These mats and these shoes - additional protection, which can not create a closed circuit if accidentally touched the conductor bare hand.In short, there is no closed circuit - no current.
And where does the ground?Anything above - only the preamble.And the ground is generally used to protect a person by touching the metal parts under voltage.Example: Bob did the heating system in the house, put the batteries in, rolled / welded pipe, but also has built electric boiler with electric heaters.Included - everything works, everything is fine, Bob walks tube probe is happy: the heat!
And at one point (what here "perfect"?) Of his heater is out of order, but closed the phase on the boiler body.So what?And the fact that the battery and the pipe is now under stress, can not wait, when someone or something does not create a circuit for current flow.And the wife Vasina floor just washed in the kitchen so taken in head rag hang on the battery, drier ... Paul raw, bare feet, wet rag ... Oh, and get Vasya, if left alive!
But if Bob did the normal contour of the ground, so your pot firmly grounded - nothing would have happened.Speaking prostetski language, would have left the phase of the ground, the current would have received in this huge breaker would not survive for a long time and this would have disabled the boiler.And even if not disabled, then the potential on batteries so the pipes connected to the ground, would be virtually zero, and so his wife would not have got.
Therefore it is necessary to ground all that has a metal body.Boilers of various kinds, even if they are not heated by electricity and gas, for example.For them, too, they are fed wire feed automatic.Where a fall over the thread of the time phase wire, or a mouse, always hungry infection, isolation pogryzet - and hello: Live on the body.Woodworkers, household different instruments.In the motor winding insulation broke - again, hello, again, the body under stress.Or a pump, for example, but you never know what else electrical in the house nagorozheno!
And you can not ignore the ground by using the mixer.Here it is a recipe for trouble if something happens.Working with water, everything raw, shoes, land around ... God forbid!
And take tea.It would seem, what is there to be?Housing plastic, insulation, as in any way.What tea can be wet?Bob slipped kettle under the tap and poured water so carelessly poured on the body fell.Only Vasya now all in-date information, and a third contact in the earthing-pin is not empty hanging, and all rank by rank: grounded.Well done John, I did everything right.
Ground.And how to do to make it all right?
It is a snap.It is necessary to organize the so-called ground loop.It consists of several metal pins driven into the ground and connected between a rod or bar in the welding.These pins are arranged on the perimeter of the house, thus creating, as it were protected area, which is aligned in the electric potential.Four pins in the corners - good.Six - even better.It is possible and more service life increase.
pin length - not less than 3 meters.Diameter steel pins - 16 mm or more.No paint on it should not be.If the pin galvanized or copper - 12 mm is allowed.If the soil
malleable vobesh their sledgehammer in a few minutes.Do not forget to only sharpen the end.The ends of the pins are interconnected by a steel band around the perimeter of the cross-section of not less than 100 square meters.mm welding.Will only cover strip hot bitumen, to less rusted.You can bury it all in the ground, it is allowed.
itself, this design will not work if it does not connect to anything.Tavern should be introduced into the house and on it in a convenient place should be welded bolts, with their help, and connect the ground wire from the same boiler and Vasya's third wire evrorozetok.
remains only one thing: to test the parameters of this structure, as they meet the standards.There will have to consult an electrician who has appropriate devices for measuring resistance, the corresponding methodology.Generally, measurements should be carried out periodically, at least 1 time in 10 years, because the pins in the ground eventually rust, electrical resistance increases.Fix it too easy: drive has a number of pin and weld them to the tavern.
That's all, and let no microwave never stings your household, any pipe or the battery is not hit.By the way: Never use as a ground pipes or central heating, God forbid, gas and sewer pipes laid in the ground.Rules may be laid in the ground to use the centralized water supply pipe, but personally I do that I would not.
All this has a connection, all this is isolated in the ground, insulated, and no one makes any measurement of electrical resistance.If Peter, your neighbor, says that he and through these pipes everything works fine - it's his problem, because it does not mean that it is protected ...