How to calculate electrical fault or Short circuit current?

basicelectricaldesign
short circuit current

Short circuit current calculation.  Purpose It plays a very important role to protect & also safety of commercial and industrial electrical equipment like circuit breakers,transformers …etc. What is short circuit current? When two or more conductors are different phases come in contact with each other in a line, transformer or any other power element, then the part of the impedance is shunted out of the circuit due to which a large current flow in the un-faulted phases, such current is called the short circuit current. It reduces the effect of impedance in…

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How to choose high voltage cable size?

basicelectricaldesign
High voltage cable

Calculation of nominal cross sectional area of the high voltage cable    High voltage cable The cross sectional area of high voltage cable where calculated shall not be less the value determined by following formula:-                                            S = (I SC *√t ) / K Where, S= Nominal cross sectional area of the conductor in mm2 I SC = Value of fault current or short circuit current in KA T=Fault clearing…

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How to calculate LT Cable Size and Voltage drop in Electrical Installation?

basicelectricaldesign
voltage drop

Cable size and Voltage drop calculation for LT / LV (Low tension/Low voltage) Purpose The purpose of this document is lay to down the guidelines and design procedure for performing the LV cable size and voltage drop calculation. Relevant IS standards:- IS:694/1990 for PVC cable IS:1554 part-1/ 1998 for heavy-duty PVC cable IS: 7098 part-1 /1988 for XLPE cable Procedure The cable size is selected base on the four following consideration:- Cable Derating Amp should be higher than Full Load Current of Load. Cable voltage drop should be less than…

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