Grounding and protective measures for electrical safety. Grounding conductors

Free technical library

ENCYCLOPEDIA OF RADIO ELECTRONICS AND ELECTRICAL ENGINEERING
Free library / Encyclopedia of radio electronics and electrical engineering / Electrician

Section 1 General Rules

Grounding and protective measures for electrical safety. Grounding conductors

Free technical library

Encyclopedia of radio electronics and electrical engineering / Rules for the installation of electrical installations (PUE)

Comments on the article

1.7.113. Cross-sections of grounding conductors in electrical installations with voltage up to 1 kV must comply with the requirements of 1.7.126 for protective conductors.

The smallest sections of grounding conductors laid in the ground must correspond to those given in Table. 1.7.4.

Laying aluminum bare conductors in the ground is not allowed.

1.7.114. In electrical installations with voltages above 1 kV, the cross-sections of the grounding conductors must be selected so that when the highest single-phase short-circuit current flows through them in electrical installations with an effectively grounded neutral or a two-phase short-circuit current in electrical installations with an isolated neutral, the temperature of the grounding conductors does not exceed 400 ºС (short-term heating corresponding to total time of protection and tripping of the circuit breaker).

1.7.115. In electrical installations with a voltage above 1 kV with an insulated neutral, the conductivity of grounding conductors with a cross section of up to 25 mm2 over copper or equivalent from other materials must be at least 1/3 of the conductivity of the phase conductors. As a rule, the use of copper conductors with a cross section of more than 25 mm2, aluminum - 35 mm2, steel - 120 mm2 is not required.

1.7.116. In order to carry out measurements of the resistance of the earthing device, it should be possible to disconnect the earthing conductor in a convenient place. In electrical installations with voltages up to 1 kV, this place, as a rule, is the main ground bus. Disconnecting the earth conductor must only be possible with a tool.

1.7.117. The grounding conductor connecting the working (functional) grounding conductor to the main grounding bus in electrical installations with voltage up to 1 kV must have a cross section of at least: copper - 10 mm2, aluminum - 16 mm2, steel - 75 mm2.

1.7.118. An identification mark should be provided at the places where grounding conductors enter the building .

See other articles Section Rules for the installation of electrical installations (PUE).

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

The world's tallest astronomical observatory opened 04.05.2024

Exploring space and its mysteries is a task that attracts the attention of astronomers from all over the world. In the fresh air of the high mountains, far from city light pollution, the stars and planets reveal their secrets with greater clarity. A new page is opening in the history of astronomy with the opening of the world's highest astronomical observatory - the Atacama Observatory of the University of Tokyo. The Atacama Observatory, located at an altitude of 5640 meters above sea level, opens up new opportunities for astronomers in the study of space. This site has become the highest location for a ground-based telescope, providing researchers with a unique tool for studying infrared waves in the Universe. Although the high altitude location provides clearer skies and less interference from the atmosphere, building an observatory on a high mountain poses enormous difficulties and challenges. However, despite the difficulties, the new observatory opens up broad research prospects for astronomers. ... >>

Controlling objects using air currents 04.05.2024

The development of robotics continues to open up new prospects for us in the field of automation and control of various objects. Recently, Finnish scientists presented an innovative approach to controlling humanoid robots using air currents. This method promises to revolutionize the way objects are manipulated and open new horizons in the field of robotics. The idea of controlling objects using air currents is not new, but until recently, implementing such concepts remained a challenge. Finnish researchers have developed an innovative method that allows robots to manipulate objects using special air jets as "air fingers". The air flow control algorithm, developed by a team of specialists, is based on a thorough study of the movement of objects in the air flow. The air jet control system, carried out using special motors, allows you to direct objects without resorting to physical ... >>

Purebred dogs get sick no more often than purebred dogs 03.05.2024

Caring for the health of our pets is an important aspect of the life of every dog owner. However, there is a common assumption that purebred dogs are more susceptible to diseases compared to mixed dogs. New research led by researchers at the Texas School of Veterinary Medicine and Biomedical Sciences brings new perspective to this question. A study conducted by the Dog Aging Project (DAP) of more than 27 companion dogs found that purebred and mixed dogs were generally equally likely to experience various diseases. Although some breeds may be more susceptible to certain diseases, the overall diagnosis rate is virtually the same between both groups. The Dog Aging Project's chief veterinarian, Dr. Keith Creevy, notes that there are several well-known diseases that are more common in certain breeds of dogs, which supports the notion that purebred dogs are more susceptible to disease. ... >>

Random news from the Archive

64MP ISOCELL Bright GW1 sensor for smartphones 09.05.2019

Samsung has announced the release of a new image sensor for mobile devices, called ISOCELL Bright GW1. It has a higher resolution than other comparable devices on the market.

The new Samsung ISOCELL Bright GW1 sensor has a resolution of 64 megapixels with the same pixel size as the previous 48 megapixel model - 0,8 microns. This means that the new product has a larger physical size and is able to capture more light, which should have a good effect on the quality of shooting. Like its predecessor, the default Bright GW1 sensor produces lower resolution images by combining four neighboring pixels into one larger pixel that can capture more light. Thus, by default, photos are 16 megapixels.

Samsung's new sensor is able to descramble the color filter for full 64-megapixel resolution shots in good light. The same feature is available on the 48MP Sony IMX586 sensor, but it was not supported on the previous Samsung device. Now, the Korean manufacturer has released an updated version of the 48-megapixel sensor with support for this feature.

Samsung plans to begin mass production of the 64-megapixel ISOCELL Bright GW1 sensor in the second half of this year. It will appear in ready-made consumer devices towards the end of 2019.

Other interesting news:

▪ Recognizing people through walls

▪ Thinness genes

▪ Chips for voice echo suppression in communication channels

▪ Biological magnetoreception

▪ Hydrogen truck Mercedes-Benz GenH2 Truck

News feed of science and technology, new electronics

Interesting materials of the Free Technical Library:

▪ site section Parameters of radio components. Article selection

▪ article Horus gave birth to a mouse. Popular expression

▪ article Against which landmark did 300 figures of French culture write a protest? Detailed answer

▪ article Explorer. Standard instruction on labor protection

▪ article Making a printed circuit board at home. Encyclopedia of radio electronics and electrical engineering

▪ article High quality IF audio amplifier. Encyclopedia of radio electronics and electrical engineering

Leave your comment on this article:

All languages of this page

Home page | Library | Articles | Website map | Site Reviews