Shady data from a transformer’s short-circuit test

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Kamakiri
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Homework Statement


Data from the short-circuit test of a 60-Hz, 100-kVA, 4600–230-V transformer are:

VSC = 172.3 V
ISC = 20.2 A
PSC = 1046 W

Get the per-unit parameters.

2. Relevant equations

ISC ≠ Irated, so how will I solve the problem?

The problem is from the book with ISBN 0130612103.
 
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Kamakiri said:
I_(SC) is unequal to the rated current, so how will I solve the problem?

Rated current is about 100 kVA / 4.6 kV = 21.7 A, so the error-ratio is 21.7 A / 20.2 A = 1.076

So you multiply Vsc and Isc by 1.076.

Multiply Psc by 1.0762. ( P = R * I2. )
 
The per-unit parameters are the same whether or not I multiplied the data by 1.076 or 1.0762.