Answer / george m s kingsley

Hai dear engineers,

MPCB- Motor Protection Circuit Breaker

It breaks the circuit depend upon the properties of the machine.
eg:- Set the breaking current of 10Amps in MPCB for the
Machine rating of 10Amps.
So that the machine take the starting current of 1.3 to 1.5
times from the rated.MPCB does not react here. But if the
current goes 120% to 150% based on time duration it breaks
the circuit.(overload relay supportive to machine)

MCB- Miniature Circuit Breaker.

It doesn't bother about Machine. If the Ampere goes more
than the MCB range it breaks the circuit.
Short circuit protection
(overload relay supportive to resistive, lighting load,
control circuit etc.)

Answer / saroj kanta nayak

1.Both MCB and MPCB protects against Short circuit and Over load. But MPCB is better for the more starting current taken by Motor. and the Current range can be ardjusted. In mcb we cannot ardjust the current.
2.Both MPCB and MCB protects against Short circuit and over load. But the main difference is MCCB have NO & NC contact built in which used for the control circuit. untill and unless MCCB made on control circuit cannot made on(for motor starter feeder) In camparision to MCB, MCCB have higher current rating. And if current rating increases ACB(air circuit breakers used).

 So in conclusion All MCB,MCCB & MPCB gives the same protection even can be used in any others place. But MPCB is best for MOTOR protection as it have Inbuilt OVER LOAD RELAY and current range can be selected. Others(MCB&MCCB) may give trouble of unnecessary tripping during starting of motors.For short circuit protection all devices like MCB,MCCB&MPCB functions similar way.

Saroj kanta Nayak
SIEMENS LTD.
KALWA,MUMBAI
Masters In technology from
Nation Institute of technology, Silchar.

Answer / chetan

MPCB-MOTOR PROTECTION CIRCUIT BREAKER
MCB-MINIATURE CIRCUIT BREAKER
MPCB TOTALY DIFFERENT FROM MCB AS IT IS NOT ONLY SIMPLE
CIRCUIT BREAKER AS MCB IT HAS INBUILT OVERLOAD RELAY RANGE
IF THE LOAD ON THE MOTOR EXCEEDS ITS CURRENT ABOVE THE
LIMIT OF MPCB IT TRIPS.
MCCB-MOULDED CAGE CIRCUIT BREAKER
MCCB IS A CIRCUIT BREAKER HAVING HAIGH LOAD CAPACITY THAT
IS ABOVE 63 AMPERE WE ARE GENERALY USE MCCB INSTED OF MCB

Answer / rohan

MCB(Miniature Circuit Breaker) which ranges from 0.5A to
63A, but now HRC MCB has rating upto 125A, anything higher
than this rating requires a design which can handle so high
current so MCCB(Moulded Case Ciruit Breaker) which has raing
upto 1000A, whereas, MPCB is used for Motor Protection Device.

Answer / amu

Dear George M S Kingsley
plz tell me what is the diff b/w lugs and thimbles in electrical field.

Answer / rajesh

MPCB means motor protection circuit breaker.its called
manual motor starter.its not a motor its also protective
eqiupment.its working range is 0.1A-25A.MCB(miniature
circuit breaker)and MCCB(molded case circuit breaker)
working range is from the above 10A.

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