IF we have 500kva transformer 11.0/0.415V, 50Hz. How to
calculate the current on HT & LT side, how can we consider
for its breaker (HT & LT both)? You are requested to solve
the question herewith.

Answer Posted / antaratara ghosh

current on HV side= 500/(1.732*11)
= 26.24 A

current on LV side= 500/(1.732*0.415)
= 695.6 A

Breaker on HV side will be 630 A VCB (since it is the
lowest available VCB and in HV side you have to go for
VCB/SF6)

Breaker on LV side will be =greater than (1.2*695.6)A i.e.
834.72 A
so we consider it to be 1000 A ACB

Is This Answer Correct ?    19 Yes 3 No



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