Answer / ankurjha

Circuit Breaker:
Device to control current drawn by the load. Has the
facility of cutting the supply in case of heavy inrush of
current/ short circuit etc..

Contactors:
device to make/ break contacts as & when required. Have
control coil which is energized/de-energized as per the
control requirement.

Isolators:
Usually meant to isolate the circuit manually, so that the
circuit can be worked upon. Have fuses for potection of
load.

Answer / iamdon

circuit breaker can make,break and carry current under
normal,short circuit and overloaded condition..It operates
automatically.

contactor can make,break and carry current under normal and
overloded conditions only but not in short circuit
condition.It can operates more no of times without
maintenance.

Isolator can break currnt only through that part of circuit
which is bot carrying any current.It is manually operated..

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