A transformer is rated at 11 kV/0.4 kV, 500 kVa, 5% r eact

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A transformer is rated at 11 kV/0.4 kV, 500 kVa, 5% r eact ance. What is the short circuit M VA of the transformer when connected to an infinite bus?

1. 20 MVA
2. 10 MVA
3. 15 MVA
4. 5 MVA

Correct Option: B

Since the transfomer is connected to an infinite bus, the p.u. impedance of the circuit will be 0.05. p.u. impedance offered by the transformer short circuit

MVA =	0.5	= 10 MVA
	0.05