1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Three phase line or phase voltage?

  1. Nov 20, 2015 #1
    1. The problem statement, all variables and given/known data
    Three loads ZA = 10∠0° Ω; ZB = 15∠-30° Ω and ZC = 20∠45° Ω are connected in star across a balanced, 3 phase, 400 V, RYB supply. Determine (a) line currents (b) Phase Voltages (c) Neutral shift voltage, VON

    2. Relevant equations

    3. The attempt at a solution
    My query is that in question I am taking 400 as rms phase voltage of supply but I saw the solution and they have done by considering that voltage as line to line rms voltage, why that is so?
    Later we should also multiply voltage by√2 but are we required to keep the solution in rms only?
  2. jcsd
  3. Nov 20, 2015 #2


    User Avatar

    Staff: Mentor

    By convention, 3 phase supplies are described by their line voltage, i.e. the voltage between any pair of phases.

    By convention, AC supplies are always described by the RMS value of their sinusoidal waveform.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted