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Just want to be clear on the CBT power PE exam, no materials are allowed in the exam correct, only the PE handbook, and the PDF's of the code books will be provided?

Can anyone tell me why Q(old)'s formula does not work for Q(new) ?  Q(old) = sqrt3*V*I*sin(theta) = sqrt3*480*34*sin(cos^-1(.75)) = 18.7 kVAR Qnew = sqrt3*480*34*sin(cos^-1(.9)) =12.3 kVAR Qnew = P*tan(cos^-1(.9)) = 21.2*tan(cos^-1(.9))= 10.26 kVAR

NEC - Table 9 - Note 2 Ze (for other than .85 PF) = R*PF+Xl*sin(cos^-1(PF)) R(1000ft)=.029 R(250ft)=.029*(250/1000) = .00725 X(1000ft)=.048 X(250ft)=.048*(250/1000)=.012 PF=.8 Ze = .00725*.8+.012*sin(cos^-1(.8)) Ze = .013 Vd = I*Ze = 400*.013 = 5.2V V = Vs(L-N)-Vd V=277-5.2 = 271.8...