Answer / kantharaju k c

MCCB-- Moulded Case Circket Breaker
ACB -- Air Circket Breaker
VCB -- Vacume Circket Breaker

MCB we use from 0 to 64 Amp.
MCCB we use from 64 to 800 Amp
ACB we use above 800 Amp

More ever at much higher current level we use VCB because
at higher current the air around it get ionised and become
conducter which causes short ckt. so at much higher current
level we generaly use VCB.

Is This Answer

Answer / sri.....

MCCB---- For Lower Operating Currents & Use And Throw
Technology.(in india generally up to 800A).
ACB --- For High Operating Currents & High end Product &
Protection Features & where Maintanance of Circuit Breaker
is required...
VCB --- For Higher Operating Voltages--- 6.6KV & above....

Answer / pankaj kumar singh

MCCB( moulded case circuit breaker),VCB(vacuum circuit
breaker),ACB(air circuit breaker) all are of different
types of breaker with same
functioning. name given them according to arc quenching
medium used inside the breaker i.e. air,vacuum,oil,sf6 etc.
all of them are used to isolate the electrical ckt by
manually as well as automatically to trip at the time of
fault in line and thus save the
circuit from damage and isolate unheathy part from
healthy one.
if the circuit is of low(voltage &current)rating we can go
ahead with MCCB or MCB.
but for high (voltage &current)rating circuit we go for
costlier Breaker that is
ACB(air circuit breaker)or VCB(vacuum circuit breaker),OCB
(oil circuit breaker),SF6 etc. because they are more
reliable and have long life.

Answer / a k shukla

MCCB( moulded case circuit breaker),VCB(vacuum circuit
breaker),ACB(air circuit breaker) all are of different
types of breaker with same
functioning. name given them according to arc quenching
medium used inside the breaker i.e. air,vacuum,oil,sf6 etc.
all of them are used to isolate the electrical circuit by
manually as well as automatically to trip at the time of
fault in line and thus save the
circuit from damage and isolate unhealthy part from
healthy one.
if the circuit is of low(voltage & current basically in
domestic wiring and for low rating machinery)rating we can go
ahead with MCCB or MCB.
but for high (voltage &current)rating circuit we go for
costlier Breaker that is
ACB(air circuit breaker)or VCB(vacuum circuit breaker),OCB
(oil circuit breaker),SF6 etc. because they are more
reliable
As on today a new trends came in practice and MCCBs are also
manufactured in low rating current previously MCCBs
manufactured not less than 63 Amps.

Answer / harnath yadav

mccb rating 63Ato 400A
ACB instoll the L.T.
VCB instoll the H.T.

Answer / kather oli

mccb s the used low rating Lt pannel.
acb s the used high rating Lt pannel.
vcb s the used high rating Ht pannel.

Answer / raj kumar

• MCCB is used for load purpose and is should used up to 1200-1500A only.

• ACB is used for low tension (LT) panel it should carry up to 4000A and more.

• VCB is used for high tension (HT) panel it means carry 11KV and low amps rating it can withstand at long time at high Voltage also.

• MCB is used for low current ranges, available up to 63A

Answer / pankaj kumar gupta

MCCB -Molded case circuit breaker
ACB - Air circut breaker.
VCB - Vaccum circuit breaker.

ACB USE IN L.T SYSTEM.
VCB USE IN H.T SYSTEM.

Answer / ebrahim.p.b

MCCB-moulded case circuit breaker
ACB-air-blast circuit breaker
VCB-vaccum circuit breaker
their functions are same.......
ACB-These breakers employ a high pressure airblast as an arc
quenching medium.The contacts are opened in a flow of
airblast established by the opening of blast valve.The air
balst cools the arc and sweeps away the arcing product to
the atmosphere.This increases the dielectric strength of the
medium between contacts and prevents from reestablishing the
arc.Consequently the arc is extinguishedand flow of current
is interrupted.
VCB-in such breakers vaccum is used as the arc quenching
medium. Since vaccum offers highest insulating strength,it
has far superior arc quenching properties than any other medium.

Answer / rabindra dhungana

MCBs are miniature circuit breakers with optimum protection
facilities of overcurrent only.These are manufactured for
fault level of up to 10KA only with operating current range
of 0.5 to 63 Amps (the ranges are fixed), single,double and
three pole verson.These are used for smaller loads
-electronic circuits,house wiring etc.
MCCBs are Moulded case Circuit breakers,with protection
facilities of overcurrent, earth fault.it has a variable
range of 50% to 100% operating current.They can be wired for
remote as well as local operation both.They are manufactured
for fault levels of 16KA to 50KA and operating current range
of 25A to 630Amps.They are used for aplication related with
larger power flow requirement.

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