what is inrush current in transformer?

Answer Posted / sudhir

inrush current is refers to maximum, instantaneous input
current drawn by electrical device when first turned on.
when a T/F is first energized a transient current much
larger than the rated T/F current can flow for several
cycles.this ts caused because the T/F will always have some
residual flux and when T/F is energized the incoming flux
will add to the already existing flux which will cause the
T/F to move in to saturation.
due to this the starting current is double the rated
value. this us not a fault, our protecting system is
designed such a way that it can with stand with this inrush
current without any tripping.

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