BS Code of practice for protective earthing of electrical installations. BS EN Earthing of power installations exceeding 1kVac. – BS Code of practice for protective earthing of electrical installations. – BS Code of. A well designed earthing system is basic for any electrical installation to avoid the systems”. Great Britain: BS “Code of practice for Earthing”. France: NF.
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This may be taken as an indication of the possible gain from driving deeper rods, etc. Effective earthing earthinb people from the risk of electric shock. Worldwide Standards We can source any standard from anywhere in the world. The finished joint should be covered with a heavy coat of bitumen. The faster, easier way to work with standards. The purpose of earthing System earthing involves the provision of a connection to the general mass of earth.
Therefore, the various factors which affect the resistance to earth and fault current capacity of the buried conductor, designated the earth electrode, should be considered. Columns 2 and 3 relate to most of the British Isles, but column 5 is more specific to marshy flats around river estuaries. This section deals only with a straight run of conductor.
It is important to ensure earthiny their resistance areas do not overlap. It is essential to measure the resistance to earth of any metalwork it is intended to use as an electrode, and to monitor its value at regular intervals afterwardsin order to confirm that it continues to provide an adequate connection to earth.
System earthing involves the provision of a connection to the general mass of earth. After construction and with the passage of time this moisture content will approach equilibrium with that of the soil, and will 4730 be dryer than when first laid.
BS +A Code of practice for protective earthing of electrical installations
The resistance R should be taken as the ratio of the voltage between the inner electrodes and the current between the outer electrodes. Manish Darji Feb 26, This may be achieved by making the dimensions in one direction large by comparison to the other two.
Foundation metalwork in concrete may be used as a ready made and effective earth electrode. To design, specify, inspect and periodically test and maintain earthing systems without endangering those who come into contact with them, users need to follow the guidelines and recommendations outlined in this standard.
The effective resistivity is also controlled by the mineral salts in the ground and the level of moisture contentwhich is why it should be remembered that readings taken long after installation can vary considerably from the original test results.
It may be considered necessary to earthig numerical eqrthing which are more complex than the formulae given below and software is available to carry out the more detailed calculations.
It should be noted that environmental conditions such as temperature have an impact on earth resistivity with a corresponding decrease in resistivity as temperature rises.
Measurements and Calculations Of Earth Electrode Systems (BS ) | EEP
Soil resistivity may be measured in a similar manner to the establishment of the resistance of the earth electrode. This model is more closely aligned to the basic theory behind the electrostatic behaviour of an earthing system componentin effect stating more clearly the interactive effect of the value of s which for practical purposes has long been set as being not less than twice the depth of the rod.
Where the structure is supported on many similar footings, earthin may be considered feasible and more satisfactory to measure the resistance of one footing before it is electrically connected to othersand before there are any other electrically paralleled footings close by.
It includes a number of editorial changes which clarify the meaning of the text and corrects values and symbols.
Customers who bought this product also bought BS EN The standard is relevant in the following sectors: Search all products by. It also defines selection parameters for the earthing arrangements and makes clear the need for careful consideration of various site conditions such as soil composition and resistivity.
Plates, if used, should be installed as small units of not greater than 1. Alternating current should not be expected to cause corrosion, but, rectification sufficient to produce a very small proportion of direct current might take place.
This gs one of the best design reference i have seen. Ideally confirmation of the combined resistance of all the electrodes should be obtained, but the earth resistance of a structure covering a large area might be quite low and an accurate measurement on a completed structure might be difficult or impossible to achieve.
Current should be passed between the two outer electrodes and the resistance R may be found as the ratio of the voltage between the inside electrodes to the earthlng conducted through the outside electrodes. Thus a pipe rod or strip has a much lower resistance than a plate of equal surface area.