Answer / amit pandey

it is the ratio of actual quantity to base quantity.

Answer / xxx

per unit impedance of a transformer is the fraction of the
voltage applied when the current is equal to the rated
current when the terminals are shorted.For example, if a
transformer has 0.05 pu impedance (on percentage terms, you
say that transformer impedance is 5%), full rated current
will flow in the primary and secondary if you apply 5% of
the rated voltage to the primary after short circuiting the
secondary terminals.In other words, if full voltage is
applied to the primary of the transformer and the secondary
terminals are shorted, the current will be 1/(p.u
impedance) p.u. ie; in the above example of the transformer
with 5% impedance, the current will be 20 p.u. (ie; 20
times the rated current).
This definition can be extended to other electrical
appliances also.

Answer / jignesh

10 db

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