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Transformer input Voltage question

  1. Nov 5, 2013 #1
    Hi, Just to clarify, If a real transformer is being supplied with lets say 100V rms from a generator, and a load is connected to the secondary via a line containing both reactance and resistance, the input voltage at the transformer primary terminals should always be 100V, no matter what is happening after this point, as all the voltage drops associated with losses etc will not have been reached yet. Am i correct?
  2. jcsd
  3. Nov 5, 2013 #2
    Not really - as the generator and the leads from the generator to the transformer is not ideal ( in the real world) -- so the total V drop at each point of the system still affected by what is effectively a voltage divider - each element has losses and has a voltage drop. A generator with light load and good voltage control - can compensate for this however.
  4. Nov 5, 2013 #3
    Thanks for the reply. So in simple terms, if the output terminals if the generator show 100v, the input if the transformer would be 100v - losses in cables connecting generator to transformer
  5. Nov 6, 2013 #4
    well the voltage on the transformer will be a little less than that at the generator but it solely depends on the length and wire used.

    Now if you will put load on the transformer secondary that load will be reflected also in the pirmary side and felt at the generator too. As long as that load is within the limits of the generator and transformer you will not see any considerable change but if the load will get bigger you will probably see a voltage drop at the primary terminals and also at the generator because they are connected and all are affected.
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