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transformer in parallel

    • 4 posts
    October 7, 2019 3:33 AM PDT

    There are two transformer in parallel with different Z%.
    Transformer1: 240/120V, Z=6%
    Transformer2: 240V/120V, Z= 6%

    The both are wired in sereis. will the total Z% be 12% ?

    • 97 posts
    October 9, 2019 6:27 AM PDT

    Ed, the way I understand percentage impedance is that it is the amount of voltage that must be applied to a transformer primary to get full load current out of the secondary windings when they are shorted.  This number allows us to calculate volt drop at full load & the short circuit current. This data is on the transformer nameplate.

    If you were to series the two transformers then I would expect that it would take twice the voltage across the two primary windings to get the full load out of each transformer secondary.  Which means 12%, in your case.