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Which chapter of BS 7671 covers the use of new materials and inventions?
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What is the current carrying capacity of flat twin and earth cable?
It depends on whether it is copper or aluminium, what its cross-sectional area is, and how it is to be installed. If you know all these things, then you can look it up in the tables provided in your country's wiring regulations. In the UK, this is BS 7671:2008 Requirements for Electrical Installations.
How do you calculate the current capacity of a cable when the cable size is known?
The current-carrying capacity of a cable depends on a number of things in addition to its cross-sectional area; these include the type of conductor, number of cores, type of insulation, whether or not it is armoured, method of installation, etc. Accordingly, to determine its current-carrying capacity, you will need to refer to your national electrical code. For example, in the UK, BS 7671:2008 Requirements for Electrical Installations contains tables for all standard cable types, specifying current-carrying capacity, voltage drops, etc.
What is phase wire?
A phase wire is the hot wire in a circuit if looking at single phase that would be the live (brown in the UK). If you are trying to find out which wire is your phase wire use a voltmeter connect the black lead to earth and red lead on the wire to be tested. If the circuit is on and you have a phase wire you will read voltage on the meter. If the circuit is off or you have the neutral(blue wire in the UK) you will read little or no volts.Notice electricity is dangerous always use common sense if you don't know what you are doing find someone who does failing that put a hand in your pocket you will have less chance of killing yourself.Answer'Phase' is the incorrect name widely used in place of the correct term, 'line'. The current version of BS 7671(2008), the IEE Wiring Regulations, has, at last, recognised the misuse of the term 'phase' in its previous editions.In the UK, a single-phase AC line conductor has a nominal potential of 230 V with respect to the neutral. In Europe, a single-phase line conductor is normally colour-coded brown; in three-phase systems, the three line conductors are colour codes brown, black, and grey.
What is resistance of earthing electrode?
It's convenient to think of the earth electrode as being surrounded by a series of increasingly-larger 'shells' of soil, through which any earth-fault current will radiate outwards. The resistance of each 'shell' is inversely-proportional to its cross-sectional area. The shell immediately surrounding the earth electrode (1, in the following diagram) will have the smallest cross-sectional area and, therefore, the greatest resistance value; as we more further and further away from the earth electrode, each subseqent shell (2, 3, 4, etc.) increases in cross-sectional area and, therefore, reduces in resistance.The further we move away from the earth electrode, the difference between the size of each shell becomes less and less significant and, therefore, the resistance between adjacent 'shells', will become less and less until, eventually, the increase in resistance, too, will become negligible.The resistance of each of these 'shells' is, of course, cumulative. So, while the rate of change in resistance is greatest in the area immediately surrounding the earth electrode, the cumulative resistancecontinues to increase until it eventually become more-or-less constant. And it is this constant value that is taken as being the resistance of the earth electrode.In practice, we cannot use an ordinary ohmmeter to measure the resistance of the earth electrode. Instead, the basis of the test is actually as follows.A small spike is laid out in a straight line radiating away from the earth electrode. The resistance is then measured between the earth electrode and the spike, using an earth megger. The test is repeated several times, with the spike moved further and further away from the earth electrode. A graph drawn from the results shows a curve which is steepest (representing the greatest rate of change of resistance) where the test spike is closest to the earth electrode, and which eventually becomes horizontal (no further rate of change of resistance). The cumulative resistance increases, until there is no further significant increase in resistance, and this value is taken as the earth-electrode's resistance. The same results will be seen in whichever radial direction the resistance is measured, relative to the earth electrode. The area, immediately surrounding the earth electrode, in which the resistance value changes is termed its 'resistance area'.For the UK, the wiring regulations, BS 7671:2008, specifies that the value of the earth-electrode resistance must be 'low enough to ensure that the potential of any exposed metalwork, with respect to earth, during an earth fault does not exceed 50 V for normal, dry, conditions'.The 'On-Site Guide', a supplement to BS 7671:2008, further specifies (section 10.3.5) that the earth-electrode resistance should 'in any event, not exceed 200 Ω'.
What is the current carrying capacity of 240 Sq mm?
A 240 sq. mm. cable has a diameter ofd=square root of 4A/3.14d= 2(square root of A/3.14)= 2(square root of 240/3.14=17.48 mm.Therefore your cable has a capacity of only 515 amperes in free air. If installed in a duct with three conductors your conductor will have an ampacity of only 350 ampers.Alternative AnswerThe answer is not straightforward, because it depends upon various factors such as the material from which the conductor is manufactured (copper or aluminium), the type of insulation employed, and the configuration of the cable (how many conductors), installation method, etc.An Appendix to BS 7671:2008 Requirements for Electrical Installations, lists cable types according to these various factors, and specifies their current ratings.
What chapter of BS 7671 covers the use of new materials and inventions?
55
In which chapter of BS 7671 would you find reference to rotating machines?
55
How many feet are in 2557 yards?
7671 ft
Which of the tests was introduced in BS 7671-2008?
BS 7671-2008 is the 17th addition of the UK electrical code book. As the tests were not stated by the question an answer to this question can not be answered.
What is the correct name for BS 7671?
Currently; "BS 7671 Requirements for Electrical Installations. The IEE Wiring Regulations" With the first amendment of the 17th edition of BS 7671 due to be issued in a matter of weeks and the "IEE" being changed to "IET" on the document, what else differs is relatively unknown at present.
What industry is covered by BS 7671?
The industry covered by BS 7671 is the electrical industry. Because rules and regulations are always changing, one can find the current regulations at the online site "Theiet".
What is in the IEE On-Site guide?
The On-Site Guide is one of several publications that provide guidance on various aspects of BS 7671:2008 Requirements for Electrical Installations, commonly known as the IEE Wiring Regulations.It provides a background on the intentions of BS 7671:2008 and provides a simple guide to that publication. Electricians, however, are responsible to ensure that they comply with the requirements of BS 7671:2008.
Which appendix discusses the ingress Protection values?
appendix 3 from BS 7671:2008
What is the sale number of the Lego AT-AP?
The All Terrian Attack Pod is numbered 7671
What is the phone number of the Colusa County Free Library in Colusa?
The phone number of the Colusa County Free Library is: 530-458-7671.
Which test was introduced in BS 7671 2008?
British standard 7671 refers to electrical wiring regulations (17th Edition). they include; Consumer units (to come into effect January 2016) Wiring in escape routes Changes to earth fault loop impedances for all protective devices Updated EIC and EICR forms Changes to definitions throughout the Regulations
What is the country code and area code of Jaitwara- Satna India?
The country code and area code of Jaitwara- Satna, India is 91, (0)7671.
