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Three phase question

Discussion in 'Homework Help' started by rmanach, Jan 21, 2009.

  1. rmanach

    Thread Starter New Member

    Jan 21, 2009
    Hello, I'm thoroughly confused by three phase right now and am working on a homework for my power class.

    Is 480/277 always WYE? The 480 refers to phase to phase voltage, where as the 277 refers to phase to neutral, correct?

    So if I have a 480/277 4 wire setup, then it has to be wye?

    If it is wye, or if it is delta - what would be my line current if I had say a 10kW load?

    I'm just confused by the notation since there is no Y in the middle (480Y277) Is that all there is to it?

    Sorry if this is a dumb question, but I thought there was some sort of standard on this notation until I came across this.
  2. MareBear


    Oct 29, 2008
  3. mik3

    Senior Member

    Feb 4, 2008
    Maybe it is wye because a delta connection does not have a neutral wire. Or maybe is a delta with a ground wire.


    I=line current (A)
    P=real power (W)
    V=line voltage (V)
    pf=power factor