Answer / ashoke

Both are used for isolating/breaking the circuit.Isolator is
used for breaking dead circuit and circuit breakers are used
for breaking live circuit.For an example A.B.switches are
isolators wheres O.C.B,V.C.B,SF6 etc.are circuit breakers.In
isolator there is no arcing due to operation for dead
circuit,so no arc quenching medium is required.But due to
live circuit there is arc quenching medium is necessary so
in circuit breakers the medium are like oil,vacuum,SF6
etc.The isolators are mainly used for protection purpose
isolation of circuit.

Answer / balram raturi

major diffrence is that isolator operates on no load &
circuit breaker operates on load

Answer / sagar kakade

Isolator is nothing but a switch which is used for just on
and off the circuit. Circuit breaker is also used for on
and off the circuit, but the major benifit of using circuit
breaker in place of isolator is to trip on major electrical
faults like, a) Earth fault, b) over load, c) Under
voltage / No voltage, d) Short circuit fault. and damage to
the human beings as well as the electrical machinaries like
transformers, HT/LT panels, HT/LT cables, can be prevented.

Answer / pillay

I just wish to add something to the above. As said isolators are
generally used to switch on or off an unloaded circuit.They are
usually manually operated but breakers are capable to operate on
their own or remotely during over current or earth fault or just
to break the circuit with the help of under voltage or no volt
coils. The important fact is they are designed to operate on
loaded condition.

Answer / chirag

isolater is off load devise and ckt breaker is on load load
device,ckt breaker operates on the signal given by relay
coneected with it, while isolater open manually.

Answer / vinoth

Isolator acts like switch and it does not have any breaking
capacity.. it is used for low rating

Breaker is also a switch but it have some breaking capacity
and withstands the fault current for few sec... it is used
for higher rating...

Answer / santhoo

Isolator ded circuit , circuit breaker live circuit

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