how to select short circuit current while selecting a MCCB? how to calculate cu

how to select short circuit current while selecting a MCCB?
how to calculate current for a given KVA and KW load?

Question Posted / satish

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how to select short circuit current while selecting a MCCB? how to calculate current for a given KV..

Answer / john

FOR A 1000KVA TRANSFORMER.
PRIMARY VOLTAGE=15000V=15KV
SECONDARY VOLTAGE=480V=.48KV
impedence =5.75%
short circuit current at primary=1000/15*1.73*.0575=670amps.
short circuit current at
secondary=1000/.48*1.73*.0575=20943amps.

Is This Answer Correct ?

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8 No

how to select short circuit current while selecting a MCCB? how to calculate current for a given KV..

Answer / prashant

The basic equation is

P= 1.732VICos(A) WHERE P = load in KW

If in KVA then convert it to KW

KW = KVA * Cos(A)

V=415

well i dnt knw regarding the short ckt selection of MCCB

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