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Why is the Norelco 1.1kW step-down device so compact?

  1. May 16, 2012 #1
    This device was recently purchased at a hardware store, and it has a wattage of 1.1kW but can fit inside a pocket with dimensions of approximately 12cm x 6cm x 3cm.

    Does it use a neodymium-iron-boron alloy with 44 times the magnetic energy density of iron as the core of a transformer, an auto-transformer, a switched-mode power supply, or a voltage divider?
    Last edited: May 16, 2012
  2. jcsd
  3. May 16, 2012 #2
    What does it do? Is it stepping down 240v AC to 120v AC ? Is it outputting DC?

    I've opened some step down device of the former kind, it just had an SCR, a small-ish inductor, and a few other parts - basically, pre-set dimmer circuit. Really nasty.
  4. May 16, 2012 #3
    It steps the voltage down from 240V AC to 120V AC.
  5. May 22, 2012 #4
    The thread originator is waiting for a response.
  6. May 22, 2012 #5


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    Looks like Dmytry has already answered your question, thread originator: it is a "nasty dimmer".
  7. May 22, 2012 #6
    it 1.1kw the maximum power it is rated to handle? in that case, it is almost certainly trading efficiency for compactness and perhaps cost... without knowing the inner workings of the device, i can only suppose that a larger voltage converter would beat it in terms of minimizing energy loss
  8. May 23, 2012 #7
    So this is basically a dimmer circuit that uses an inductor as the voltage divider, just like an auto-transformer.
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