how to calculate circuit breaker capacity
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Answer Posted / hari
If u have the fault mva and the voltage level at which the
CB is to be installed then :
Normal current would be the continuous current flowing in
the line ( u can take the next higher value from standard
values to take care of over current)
Breaking capacity would be tha fault MVA.
Rated symmetrical breaking current in kA would be Fault
MVA*1000/(1.732x Voltage in kV)
Rated making ct would be peak value of symmetrical breaking
current i.e 2.55 times breaking current
Short time rating would be rated symm breaking ct for 3 secs
| Is This Answer Correct ? | 95 Yes | 17 No |
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