Search results

If given impedance in ohms, is it assumed to be per phase or all 3 phases combined? Came up at work and can't find the info anywhere

Problem states impedance = 0.050+j0.050 ohms, 3 phase, and with a fixed 50A current. Question is to determine differences in voltage drop with unity pf, zero pf, and 0.707 lagging pf. Solution uses NEC Chapter 9, table 9, V = I(XsinΦ + RcosΦ), and since X=R, voltage drop proportional to...

I found 2 errors when reviewing my notes: "An open circuit test of a transformer always has" Answer is (B), rated voltage (which is true) However, with the transformer at rated voltage, it will also make sound since there is rated voltage applied. also - if you look at the answer, it states...

Problem is related to voltage drop: In the 3 phase system, a bus serves a 230A lagging power factor of .75 (3) 350 wag copper conductors are held in a PVC conduit. With a 500' feeder, calculate voltage at the load (600V source) Table 9 provides feeder impedance for unity power factor and for...

Hi all, I've been lurking on here the last 6 months buying up all the used textbooks and sample exams I could afford. I am prepping for the October PE in power, and everything is coming along pretty well... Except for a few "fringe type" topics... In the spin-up practice exams, there are...