Earthing Calculations

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    28-Nov-2015

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An excel sheet for calculations of earthing requirements for a building

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<p>BS 7430EARTHING RESISTANCE ANALYSIS CALCULATIONS BASED ON BS 7430 : 1991R =18.1313407333k =150.2233325932F =0.6128803578a =0.1463723975S =199.702665905F =0.4444017237A.SELECTION OF AN EARTHING CONDUCTOR AND CONNECTION TO AN ELECTRODERn =3.9097370457F =0.3653169419Rh =1.3751199544Rn1 =0.61288035781. AVERAGE FAULT CURRENT, KA30Rn2 =0.84278400972. FAULT CURRENT DURATION 1 or 3 SECONDS ( 1 or 3 )1160Rn3 =0.84278400973. EARTH. CONDUCT. MATERIAL, COPPER or ALUM. or STEEL ( C or A or S )Cno. of electodefactorno. of electodefactor4. INITIAL TEMPERATURE, DEG.C70or110011005. FINAL TEMPERATURE, DEG.C250210022.71006. EARTHING CONDUCTOR CROSS SECTIONAL AREA, MM2199.7031.660034.51007. NEXT HIGHER STAND. EARTHING CONDUCTOR CROSS SEC. AREA, MM224042.150045.4800FINAL TEMPERATURE, DEG.C52.540056.1400B.VERTICAL RODS(150,200,250,450,500 for copper)62.870066.6300(150,200,300,500 for aluminum)73.150077.03001. RESISTIVITY OF THE SOIL, OHM.METER10083.390087.36002. LENGTH OF ELECTRODE, METER693.610097.65003. DIAMETER OF ELECTRODE , METER0.01905NO. OF ELECTRODES :103.8100107.97.9104. ARRANGMENT OF ELECTRODES, LINE or SQUARE or RECTANGLE or TRIANGLE ( L or S or R or T)R(2,3,4,5,6,7,8,9,10 for L)00123.32005. TOTAL NO. OF ELECTRODES IN LINE or IN SQUARE or IN RECTANGLE or IN TRIANGLE36(4, 8,12.16,20, 24, 28, 32, 36, 44, 52, 60, 68, 76 for S or R)148.67006. DISTANCE BETWEEN ADJACENT RODS, METER6(length / width </p>