Answer / 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.

Answer / gunasekaran

breaking current is always rms value making current are peak
current. because at the fault condition breaker will be re
closing at sub transient condition. at subtransient
condition current is more so the designed making current
value is less it will burn. so making current always more
than breaking current. it is about 2.5 times of breaking
current.

Answer / aqeel

Making current implies dc component so it is 2.5 times
breaking current

Answer / palani

The CB breaking current is less than Making current. The
breaking occur at the zero of the alternating Current where
as making occur at any amplitude of current in the
alternating current .

Answer / sudar

Which one more save opening CB at capasitive or inductive
condition???

Answer / sagar hingmire

Bcoz If making current capacity is not greater than
breaking current then if fault is there on electrical
system & ur going to close CB then very high fault current
will flow through CB and CB will get damaged or blast as
fault is not cleared.

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