Why is making current of CB always greater than CB breaking burrent?.
Answer Posted / john henry
Making capacity is the MAX current that a CB can pass at
the occurence of fault.
And breaking capacity is the RMS value of current at which
CB can break its contacts open.
Now when fault occurs, system goes into the subtransient
state and a huge amount of current flows in the system.
and this time if the breaker is reclosing and the making
capacity is low it will burn so it is high.
Breaking is low so that it can be isolted from the system
as soon as the fault occurs with less arching and to save
the contacts of the breaker.
| Is This Answer Correct ? | 35 Yes | 3 No |
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