Answer / rajendran m

Contactor is not tripping device

Breaker is tripping device

Answer / ajit

contactor use to make contact bitween two pointsof
sircet ,and in other hand breaker is a electrical divice
which is use for break thecontact point in a sircet.

Answer / suresh

both are circuit interupting devices. contactor is used for
interupting low currents and breaker is used to interrupt
high currents.

Answer / bala

contactor:
A contactor is an electrically controlled switch used for switching a power circuit, similar to a relay except with higher current ratings.

circuit breaker:
A circuit breaker is an automatically operated electrical switch designed to protect an
electrical circuit from damage caused by overload or short circuit. Its basic function
is to detect a fault condition and, by interrupting continuity, to immediately discontinue
electrical flow......

so finally,contactor used for switching.......and circuit breaker is used for to protect a circuit.so that one is interrupt device.....

Answer / dinesh chaudhary

contactor is simply used to make the contacts between two
ckts of low rating while breaker works when relay commands
i.e. relay is used as a sensing device which sense the
abnormal condition & command to the ckt breaker to brek the
ckt.

Answer / vijay krishna rao

Yes both are tripping devices. But for breakers to trip,
relays send respective (frequency,voltage,current) signals
and accordingly trip based on the settings. Contactors trip
with no intentional time lag as soon as the voltage falls
below (may be 0.6-0.7 p.u), no signalling devices are used.

That's why one may have come across a situation, when there
is a grid fault and generator trips on auxillary motors
failure. As there (aux motors) are contactors present and
for a fault voltage drops, so contactors trip.

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