Step Down Transformers

Discussion in 'General Electronics Chat' started by Gumps, Mar 10, 2009.

  1. Gumps

    Thread Starter New Member

    Mar 10, 2009
    Hello all,

    Please help me understand...I bought locally sold plug in the wall step down transformers to adapt my U.S.120V stuff to 230V house power in Australia. The largest transformer is a 2000W step down. The question is, if the transformer is plugged into the wall (230V) and the devices that are powered by it are off, is power being consumed? The transformer, even though the devices are off, gives off heat.

  2. leftyretro

    Active Member

    Nov 25, 2008
    Yes, if it gives off heat then it is dissapating energy. Transformers have internal losses and that is what you are seeing.

  3. Gumps

    Thread Starter New Member

    Mar 10, 2009
    Thanks...I kinda thought so.

    Is there a calculation to determine power consumed? I have had higher than average power bills and I was wondering if these, which I have left plugged in, are a big contributor.

  4. Mike33

    AAC Fanatic!

    Feb 4, 2005
    They contribute, for sure. If you care to, you could break the line going to the transformer and measure the current used at rest ('quiescent current', or energizing current'). Then E*I=P in watts. Or just unplug them all when not in use and keep an eye on the electric bill ;o)
  5. b.shahvir

    Active Member

    Jan 6, 2009
    Transformers on no-load or standby are one of the largest contributors of envirommental pollution as the generated electrical energy (especially if thermal power plants are considered) is unduly wasted in the form of losses.

    Dats the reason why utility companies always advice its consumers to switch off their appliances from the mains recepticle to curb power wastage due to quiescant currents!
  6. aramuster

    New Member

    Mar 25, 2009
    yes there is copper loss and magnetizing loss when operating transformer at no load. (^_^)