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Transformer and watt or VA relation?

  1. Mar 28, 2010 #1
    Hi friends
    it is not ( problem or numerical) just i want know


    friends if i have 15kva transformer .
    then can i say it can carry 1500 watt 10 (split AIR conditioners) as a load.
    and what happened if i add 5 more (split AIR conditioners) in same case. just give me idea please.theoretically


    Additional Details
    15kva transformer is step-down give 220 volt r.m.s output and
    AIR conditioners (a.c)(with common power factor) also can operate on 220 volt or 1500 watt each.
     
  2. jcsd
  3. Mar 29, 2010 #2
    No! Because:

    Str should be greater than Pl/PF

    However:
    Str = 15 KVA
    Pl = 10 X 1.5 = 15 KW
    PF <1

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    Creative thinking is enjoyable, Then think about your surrounding things and other thought products. http://electrical-riddles.com
     
  4. Mar 29, 2010 #3

    Sir please explain more for me. if you can.....
    i cant understand this.

    thanks a lot
     
  5. Mar 31, 2010 #4
    sorry! I can not.
     
  6. Mar 31, 2010 #5

    russ_watters

    User Avatar

    Staff: Mentor

    I would say you can because the odds of all 10 being on at the same time are low. That's called "diversity".

    M.S.J.'s point, though, was that the difference between kva and kw is power factor. Because of power factor, a reactive load draws a higher kva than kw.
     
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