Answer / iamdon

Basic difference between circuit breaker and contractor is
that
A circuit breaker can make,break and carry current in all
conditions i.e normal,overload and short circuit where as a
contractor can make,break and carry only in normal and
overloaded condition not in short circuit condition.
Also, Contractor are always backup by HRC fuse where as
there is no need of any backup in circuit breaker.
The frequency of operation of contractor is more than the
Circuit breaker

Answer / nishad

Above answer is almost ok. How ever I just add a little
with that.

Basic difference between circuit breaker and contractor is
That, A circuit breaker can make, break and carry current
in all conditions i.e normal, overload and short circuit.
It will protect the system from over load, Earth fault &
unbalance as well as it has different load & trip setting
and it don’t want any fuse back up. That was not inbuilt in
contactor. A contractor can make, break and carry only in
normal and overloaded condition not in short circuit
condition. Also, Contractor are always backup by HRC fuse
where as there is no need of any backup in circuit breaker.
For frequent operation, contractor is more efficient than
the Circuit breaker.

Answer / jinal kania d

A Circuit breaker is a simple switch,it can make,break and carry current in normal,overload and short circuit condition.,while Contactor has two types:Auxilary and Power contactor,it can make,break and carry only in overload and normal condition.It has back up protection compulsary by HRC fuses.,While there is no need of back up for circuit breaker.

Answer / vipin singh

1.Circuit Breaker is used to protect the circuit and connected devices whereas contractor is used for controlling purpose.Thus, C.B. is a protective device whereas Contactor is a controlling device.

Answer / rajesh ku sahu

Basic difference between circuit breaker and contractor is
That, A circuit breaker can make, break and carry current
in all conditions i.e normal, overload and short circuit.
It will protect the system from over load, Earth fault &
unbalance as well as it has different load & trip setting
and it don’t want any fuse back up. That was not inbuilt in
contactor. A contractor can make, break and carry only in
normal and overloaded condition not in short circuit
condition. Also, Contractor are always backup by HRC fuse
where as there is no need of any backup in circuit breaker.
For frequent operation, contractor is more efficient than
the Circuit breaker.

Answer / salim

Contactor is prefered selection for smaller motor feeder as they are smaller in size compared with circuit breaker for the same rating , contactor is design for more frequent operation.contactor is sentitive to voltage variation compared to circuit breaker

Answer / sushil kumar sharma

circuit breaker is normally used as main incomer in mcc panel or outgoing feeder in power transfer feeder (PCC)
it can operate fully auto or mannualy it has property of tripping at over load
contector is normaly used as motor starter or control switchgear .

Answer / chander pal

circuit breaker used for higher rating as contactor used for
low rating equipment.. both operates in auto mode command
given by relay or manually.

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