Grounding the hulls and other parts of production and household electrical installations, not usually under voltage, allows you to remove the electrical current into the soil. This is provided for by the rules for the safe operation of consumer electrical installations and applies to the flanges of supporting insulators, panels and cabinets of control, knobs of disconnectors, the housing of the measuring transformers, welding machines, and other equipment. Installation of the grounding system involves the installation of grounding pins and mounting grounding conductors attached to the electrical equipment enclosures.

Basic requirements for grounding welding equipment

Grounding the welding machine representing a stationary installation is performed in order to ensure its safe operation. Basic grounding requirements in the following:

1. All inactive parts of electric welding installations and one secondary outlook are ground.
2. Welding equipment must be equipped with a special contact in (the form of a bolt or stud) designed to attach grounding.
3. The grounding bolt must be with a contact pad, indicated by a special ground sign.
4. Serial grounding of multiple settings is prohibited: For each, a separate connection point must be provided.

Portable welding automatic installations and semiautomaticates connected to an AC network over 42 V (and more than 110 per permanent) are also equipped with grounding contacts. In the case when the grounding (reinforcement) cannot be applied or the ground installation is difficult, electrical equipment must have an RCD (protective shutdown device).

Grounding can be used for lightning protection device.

For objects powered by a downstream transformer with a deaf-free neutral and voltage on the secondary winding of 380/220 B, the re-ground is arranged at entering. At the same time, the resistance of the grounding circuit, according to Pue, should not be a large 10 ohm. In order to provide such parameters, it is necessary to use earthing machines with a large contact area and good conductivity. Their surface must be cleaned from oil and paint. Suitable for this:

• metal pipelines (except those associated with combustible liquids and gases);
• metal cable shells;
• casing;
• foundation elements.

Mounting circuit The grounding circuit in this case should provide for double connecting to the grounding highway. Welding is used to connect earthingers to grounding conductors. At the same time, the welding seam should be twice the wider rectangular shape of the conductor (in section) and six times round. If the welding cannot be used - clamps are used, which, as well as welding seams, protect against corrosion of the bitumen layer. Before the imposition of the clamp, the surface of the natural earthinger in this place should be cleaned.

In explosive rooms, natural grounding can only be used as an additional. The main thing should be an artificial ground, made in accordance with PUE.

The inner circuit of the ground is attached to the anchor bolts directly to the wall. In places of their intersection with cables or pipelines provide protection from pipes. In rooms with a high level of dampness and acidity, the inner contour of the ground is fixed on supports at a distance of 100 mm from the walls.

Varieties of earthing

In the absence of natural earthingers, the outdoor ground circuit is mounted, to which the corresponding conclusions and terminals of electrical equipment are attached.

Artificial grounding can be implemented from vertical or horizontal earthing. For vertical, pipes from steel or corners, which connect to each other, resulting in a circuit. Connecting elements are horizontal earthing: It is used for this metal strip thickness of at least 4 mm or a round cross section of the armature with a diameter of 10 mm.

Horizontal earthingers can be made in the form of metal stripes embedded on the bottom of the kittlers prepared for the construction of the foundation. The strips are located in such a way that their largest surface is focused towards the Earth. The cross section of the bands is 30 × 4 mm, a round steel armature with a diameter of 12 mm can be used.

It is not allowed to use aluminum to create a bellged ground, since this metal is quickly destroyed in the soil from the electrocorrosion.

Where the installation of horizontal grounding is impossible (for example, due to the lack of a land plot free from asphalt and other communications), the technology of deep grounding is applied. At the same time, metallic rods are introduced into the ground in a soil in various ways: the end of each of the following is connected to the previous one, forming a ground with a large contact area.

How is the horizontal ground

Ground installation technology is simple. It is used to perform the works of Bulgarian with a circle for metal, welding, sledgehammer and a metal brush for stripping the places of welding. The whole process consists of the following items.

1. We harvest the necessary materials. You will need:
   • the strip of the same material is 40 × 4 mm or a round wire (reinforcement) with a diameter of 10 mm;
   • hot-zinc corners of 2.5 m (cross section of 50 × 50 × 5 mm - 3-4 pcs).
2. We compile a project in which there is enough space for the adjacent territory for the location of the vertical electrodes at a distance exceeding their own length (that is, more than 2.5 m).
3. There is a trench of a width of about 400 mm depth of 700-800 mm.
4. In the outlined places, the corners with sharpened tops are clogged with a sledgehammer, leaving on the surface of 200 mm.
5. Welding the ground loop is performed: the metal strip is welded to the tops sticking over the ground.
6. Grounding welding with wire or tire laid to a distribution shield or control cabinet.
7. Welding the grounding band with corners and connecting wire is covered with bitumen mastic to protect against corrosion.
8. All elements covered with earth, which is then compacted.
9. Measured grounding resistance.
10. If the result is greater than 4 ohms, it is necessary to add another vertical element, which is connected by welding with the remaining structure.

Mounting a vertical depth of earth

Besides saving space, deep ground has another advantage: due to contact with the lower, dense and groundwater saturated soil layers achieves good conductivity.

Installation of ground with his hands in various ways. The choice depends on the soil properties in the area:

• for loose rock indentation applied, screwed in and harvesting of electrodes consisting of individual cores;
• a dense and frozen ground electrodes immersed method or vibro pile;
• in rocks electrodes deep into specially drilled well.

Electrodes, depending on the soil, using different. They are square, angled and round. The cross section is chosen for their soft soils in the range 12 - 14 mm (if driving depth sufficient to 6 m), to dense soils and considerable driving depth (over 10 m) section of the electrodes should be 16 - 20 mm. For driving depth using special vibrators, in other cases it is enough use a jackhammer or a powerful punch.

If the properties of the soil is not known, the installation of deep ground are as follows.

1. Harvest electrodes required length.
2. Scoring the first segment of the earthing and grounding resistance is measured.
3. To the upper end of the segment clogged welded the next element, and clog it.
4. Again take measurements so continued until, until they get the desired value of ground resistance.
5. To the upper end of the depth of the electrode is welded or bus wire whose other end is led into the enclosure or shield.