Inrush current in transformer? what does it mean?

Question

Inrush current in transformer? what does it mean?

Answer 1

it is maximum current the transformer draws in moment when it is connected to a power source

Answer 2

When a transformer is not energized, there is no magnetic flux inside the core.  In order to energize a transformer from 'zero' there must be current applied to initialize the flux.  That is part of the in-rush current.

Also... if the transformer secondary is connected to a DC power supply, there are more-that-likely large capacitors that must be charged.  This also takes extra current, which contributes to the in-rush.

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