1、ElectricalCalculationsHandbookEC&MsThis page intentionally left blank.EC&MsElectricalCalculationsHandbookJohn M.Paschal,Jr.,P.E.McGraw-HillNew YorkSan FranciscoWashington,D.C.AucklandBogotCaracasLisbonLondonMadridMexico CityMilanMontrealNew DelhiSan JuanSingaporeSydneyTokyoTorontoCopyright 2001 by T
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11、its licensors be liable for any indirect,incidental,special,punitive,consequential or similar damages that result from the use of or inability to use the work,even ifany of them has been advised of the possibility of such damages.This limitation of liability shallapply to any claim or cause whatsoev
12、er whether such claim or cause arises in contract,tort orotherwise.DOI:10.1036/0071414800ContentsPrefacexiiiChapter 1.Basic Electrical Working Definitions and Concepts1Voltage as Potential Difference1Current3Resistance4Direct-Current(dc)Voltage Sources4Direct and Alternating Current5dc Voltage6Curre
13、nt Flow in a Resistive Circuit15Current Flow in a Series Resistive Circuit16Voltage Division in a Series Circuit18Power Rating of a Resistor18ac Voltage23ac Circuits with Resistance23ac Phase Angle and Power26Current and Power in a Single-Phase ac Circuit33Current and Power in a Three-Phase ac Circu
14、it33Inductive Reactance42Capacitive Reactance46Impedance52Chapter 2.Three-Phase Systems55Wye-Connected Systems58Delta-Connected Systems60vxi For more information about this book,click here.List of Problems Copyright 2001 by The McGraw-Hill Companies,Inc.Click here for Terms of Use.Chapter 3.Mathemat
15、ics for Electrical Calculations,Power Factor Correction,and Harmonics69Changing Vectors from Rectangular to Polar Form and Back Again69Adding Vectors70Multiplying or Dividing Vectors74Solving for Current and Power Factor in an ac Circuit Containing Only Inductive Reactance75Solving for Current and P
16、ower Factor in an ac Circuit Containing Both Inductive Reactance and Resistance in Series with One Another77Solving for Current and Power Factor in an ac Circuit Containing Two Parallel Branches That Both Have InductiveReactance and Resistance in Series with One Another77Solving for Current and Power Factor in an ac Circuit Containing Parallel Branches,One of Which Has InductiveReactance and Resistance in Series with One Another and the Other of Which Has a Capacitive Reactance79Electrical Power