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Amperage used versus amperage billed

  1. Feb 12, 2014 #1
    Hello all,

    I'm new to the forum, and hoping someone in here can help figure out the answer to my dilemma. I'm debating whether to build a new phase converter for a 3 phase welder, or reconfigure my current welder from 230VAC to 460VAC. I know the standard equation for watts is- Watts = Volts x Amps. If I run my current single phase welder off a 460 transformer, I can reduce my amperage by half from 90 amps- maximum AC input, to 45 amps.

    In short, am I going to be supplying my transformer with 45 amps as the meter sees it, or 90 amps?

    Thanks in advance,

  2. jcsd
  3. Feb 12, 2014 #2
    I'm pretty sure you'll have 90 A going into the 230 V side and 45 A coming out of the 460 V side so that the power going into the transformer is the same as the power coming out. So you'll be drawing 90 A from the meter at 230 V, and then converting that to 45 A at 460 V.

    Transformers don't follow the "current in = current out" rule. If you look at a diagram for a transformer, the current on the input is completely separate from the current on the output aside from the magnetic coupling.
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