Today we’ll talk about electrical safety, how to make grounding. The Rules for Electrical Installation (PUE), this bible for electricians, makes it very clear that electrical equipment must be connected to the ground loop. This is not a whim, but a requirement, following which in many cases allows you to save a person’s life.
Let's take a close look at the power cords of an automatic washing machine or electric water heater. Manufacturers placed special tags on them with a reminder that these household appliances should be connected to an electrical network with grounding. It is unlikely that anyone will doubt the correctness of such a connection. The problem is that in residential buildings and apartments of the Soviet era, there is no ground loop. Even if it is, then no one bothered to bring a third, grounding wire to outlets and devices - such was the standard. Accordingly, no one was interested in how to make grounding. This is easily explained if you recall the number of electrical appliances in the average house: a radio, a lamp, an iron and a TV. Now everything has changed - there are more devices, respectively, the potential danger has increased. It is not surprising that on online forums the question is often asked: "How to make grounding?" Fortunately, this task is easily solved.
Next, we will talk about how to make grounding in a private house. Of course, you can simply drive a metal pipe into the ground and bring a wire to it, but the effectiveness of such a solution may be insufficient. The rules of the grounding system are clearly regulated, and they indicate a loop resistance of 4 ohms. Banal clogging of the pipe may not provide the desired value. In this case, how to make grounding? Electrodes should be prepared - these can be metal rods, pipes, corners with a length of at least 2 meters. Although copper conductivity is one of the highest, this metal from contact with air is coated with a poorly conductive oxide, so ordinary steel is used. In addition, it is much cheaper.
If you decide to use a corner, then its cross-sectional area should be at least 150 mm square. - this is necessary to ensure sufficient contact with the soil. If rods are taken for the electrodes, then their diameter should be at least 10 mm. More stringent requirements are imposed on pipes: the wall thickness should be 3.5 mm or more with a diameter of 32 mm. Future electrodes should not have paint, varnish, or any other insulating layers.
To create the simplest system, it is necessary to draw a triangle on the ground with a side distance of 1.2 m. Next, according to the drawing, you need to go deep by half a meter, place the electrodes in the corners and hammer them with a sledgehammer. After that, they are connected by a conductor - a metal strip or a rod of large cross section (not less than 50 mm square), welding the system together. We bring this conductor underground to the house and bring it to the surface near the wall. Fasten to the wall with dowels. We weld a bolt to the strip (rod) with a hat. It remains to lead the line with a copper (6 mm sq.) Or aluminum (16 mm sq.) Wire to the home switchboard, and from there - a third wire throughout the wiring.
But how to make grounding in the apartment, living on the upper floors? In high-rise buildings, there is always a contour, it’s just that it is not brought into residential premises. You will have to pull the line to the site on the stairwell, where the shield with metering devices and automatic machines is located. This is where you can find the grounding bus and connect to it. Next, the extended wire must be led to your apartment and distributed throughout the wiring, turning it into a three-wire cable with grounding. As you can see, with this method you don’t need to dig anything, so the work is faster.