so calculating FC on an infinite bus is easy but how do you calculate it by hand for a finite bus?(adsbygoogle = window.adsbygoogle || []).push({});

here is the concept i am having an issue understanding:

let say i have a transformer that is 225KVA with 5%z and 3 phase 480 to 208.

with infinite bus i have 12491A available on the secondary of this transformer IF 12291A is flowing on the secondary then based on the voltage ratio and OHMs law 5412.8 A is flowing on the primary.

If this is true then what does it matter if i have infinite amps available on the primary or i have 5412.9 amps available 12491A should still flow in my mind.

I have run this in SKM and i see that it does matter but i just dont understand why.

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# Fault current on finite bus

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