Answer / snowwhite10

isolator is a knife switch and it is used to open a circuit
under no load.such switches are used in the both sides of
the circuit breakers so that repair and replacement of the
circuit breakers could be done.they are never opened when
current is flowing in the line.....

circuit breaker is an equipmnet which can make or break
contacts under load ,no load or fault conditionsrelay is
always used with circuit breaker ..relay detects the fault
and circuit breakers does the function of current interruption..

Answer / boozzoo

1.)isolator works only at no load,if operated on load there wil b dangerous sparking....whereas ckt breaker wrk on load as well
2.)isolator doesnt have any arc quenching mechanism unlike ckt brkr which have many means oil vaccuum etc

Answer / kundanmalani1990

Isolater work as a switch.and not to clear to fault condition.only no load opration means cb to maintance so the use to the isotater and cb are use to the disconnect to the faulty section.

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